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Cited by 169Virus-based gene therapy researchAlzheimer's disease research and treatmentsRNA Interference and Gene Delivery

AAVrh.10-Mediated APOE2 Central Nervous System Gene Therapy for APOE4-Associated Alzheimer's Disease

Open access
Rosenberg, Jonathan B., Kaplitt, Michael G., De, Bishnu P., Chen, Alvin, Flagiello, Thomas, Salami, Christiana, Pey, Eduard, Zhao, Lingzhi +9 more·2018·Human Gene Therapy Clinical Development
DOI 10.1089/humc.2017.231PMC PMC5870071
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Abstract

Alzheimer's disease (AD) is a progressive degenerative neurological disorder affecting nearly one in nine elderly people in the United States. Population studies have shown that an inheritance of the apolipoprotein E (APOE) variant APOE4 allele increases the risk of developing AD, whereas APOE2 homozygotes are protected from late-onset AD. It was hypothesized that expression of the "protective" APOE2 variant by genetic modification of the central nervous system (CNS) of APOE4 homozygotes could reverse or prevent progressive neurologic damage. To assess the CNS distribution and safety of APOE2 gene therapy for AD in a large-animal model, intraparenchymal, intracisternal, and intraventricular routes of delivery to the CNS of nonhuman primates of AAVrh.10hAPOE2-HA, an AAVrh.10 serotype coding for an HA-tagged human APOE2 cDNA sequence, were evaluated. To evaluate the route of delivery that achieves the widest extent of APOE2 expression in the CNS, the expression of APOE2 in the CNS was evaluated 2 months following vector administration for APOE2 DNA, mRNA, and protein. Finally, using conventional toxicology assays, the safety of the best route of delivery was assessed. The data demonstrated that while all three routes are capable of mediating ApoE2 expression in AD relevant regions, intracisternal delivery of AAVrh.10hAPOE2-HA safely mediated wide distribution of ApoE2 with the least invasive surgical intervention, thus providing the optimal strategy to deliver vector-mediated human APOE2 to the CNS.

AI snapshot

Written from the paper’s full text.

TL;DR

In nonhuman primates, AAVrh.10-mediated delivery of HA-tagged human APOE2 to the CNS produced widespread APOE2 DNA, mRNA, and protein expression in AD-relevant brain regions by intraparenchymal, intracisternal, and intraventricular routes. Intracisternal delivery was selected as optimal because it achieved broad CNS distribution with the least invasive surgical intervention and no vector-related safety signals over 8 weeks.

Key findings

  • All three routes mediated ApoE2 expression in AD-relevant regions; intracisternal and intraventricular routes produced widespread CNS distribution. Intracisternal delivery gave higher vector DNA distribution than intraventricular (p < 0.001), while mRNA and protein expression were similar (mRNA p > 0.5; protein p > 0.7).
  • For intracisternal delivery, 92.0% of brain cubes had vector DNA >1,000 copies/μg DNA, 81.3% had APOE2 mRNA >1,000 copies/μg DNA, and 68.1% had ApoE2-HA protein >22 ng/mg, versus control cubes at 3.9%, 2.9%, and 3.0%, respectively. For intraventricular delivery, the corresponding values were 90.0%, 86.0%, and 51.5%.
  • CSF ApoE2-HA levels were consistently >1 μg/mL above endogenous background at both post-administration time points for both intracisternal and intraventricular routes, with no significant difference between routes (p > 0.9).
  • Safety assessments showed no adverse events or abnormal results; vector groups did not differ from sham controls in general assessment or comprehensive blood profile, and no vector-associated pathology was found beyond focal needle-tract changes. Anti-AAVrh.10 total and neutralizing antibodies developed after administration.

Methods

  • AAVrh.10hAPOE2-HA, an AAVrh.10 vector coding for HA-tagged human APOE2 cDNA, was administered to adult male African Green monkeys by three CNS routes: intrahippocampal (n = 2; 5 × 10^12 gc total), intracisternal (n = 3; 5 × 10^13 gc), and intraventricular (n = 3; 5 × 10^13 gc). A dual intracisternal plus intraventricular cohort (n = 3; 1 × 10^14 gc total) was used for safety assessment, with sham/PBS controls.
  • At 8 weeks after administration, brains were sectioned into 1 cm³ cubes for quantitative TaqMan PCR of vector DNA and APOE2 mRNA and ELISA for ApoE2-HA protein; left hemispheres and spinal cord were assessed by anti-HA immunohistochemistry. CSF was analyzed by Western blot and ELISA.
  • Safety was assessed by hematology, serum chemistry, anti-AAV total and neutralizing antibody titers, blinded behavioral videotape scoring, MRI, necropsy, and histopathology. Statistical analyses used one-way ANOVA with Dunnett’s test, two-way repeated measures ANOVA, and t-tests, with significance set at p < 0.01 due to small sample size.

Limitations

  • The paper states the study cohort was small (n = 3/group for most routes; n = 2 for intrahippocampal), and statistical comparisons were considered significant only at p < 0.01 because of small sample size and daily variations in cell numbers and serum chemistries.
  • The paper states this is a nonhuman primate study with 8-week follow-up; it assesses CNS distribution and safety, not clinical efficacy in humans or reversal/prevention of AD.
  • Evident from the text: no cognitive, amyloid burden, or disease-progression outcomes were measured; the HA tag was used to distinguish vector-derived APOE2 from endogenous APOE2, and some safety comparisons used historical controls.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1089/humc.2017.231

Cites

104 of 104 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

74 of 134 cited sources checked · 18 supported · 10 flagged · accuracy not yet measured

  • Premisecitation
    § Introduction

    Equivalent expression of E2 almost cancels out the deleterious effect of the E4 allele.

    “and equivalent expression of E2 almost cancels out the deleterious effect of the E4 allele.6,14,15”
    Quote in the paperSubstantial claim2 of 3 sources checked
    • cites [6] Genin E, 2011, Mol Psychiatry source

      The Results (page unavailable) report an Alzheimer disease odds ratio of 2.64 for APOE 24 relative to APOE 33. Although the Introduction describes APOE 2 as protective, the elevated risk for people carrying both E2 and E4 contradicts the claim that E2 almost cancels E4’s deleterious effect. The paper does not assess equivalent expression of the two alleles. (LLM, conf=0.88)

      Checked by a reasoning model — may be wrong.

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    • cites [14] source
    • cites [15] source

      In “APOE ε4 as a strong risk factor for AD” (page unavailable), the review reports an Alzheimer disease odds ratio of 2.6 for ε2/ε4, versus 3.2 for ε3/ε4 and 1 for the ε3/ε3 reference group. That suggests some attenuation, not near-cancellation of ε4-associated risk. The passage compares genotypes; it does not establish equivalent expression of the two isoforms. (LLM, conf=0.87)

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  • Findingcitation
    § Results

    Overall gross and microscopic pathology showed no effects of the dose/volume of vector beyond focal superficial parenchymal loss due to surgical intervention, similar to that observed in previous studies with PBS-treated controls.

    “Overall gross and microscopic pathology showed no effects of the dose/volume (5 × 1013 gc and 1 mL of vector per CSF site) of vector beyond focal superficial parenchymal loss due to surgical intervention, similar to that observed in previous studies with PBS-treated controls.31”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [31] source

      The Results report superficial cortical loss and needle-track changes in PBS-treated controls, consistent with surgical injury. But the Discussion says additional inflammatory and degenerative lesions occurred in vector-treated animals, not PBS controls, and that vector involvement was probable. The Results also give a total dose of 1.5 × 10¹² genome copies per animal, not 5 × 10¹³ per CSF site. (LLM, conf=0.90)

      Checked by a reasoning model — may be wrong.

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    • Rests on an assumption: The 8-week post-administration period is sufficient to assess long-term expression and safety.
  • Premisecitation
    § Discussion

    AAV2 transduction is restricted to pyramidal and granular cells.

    “AAV2 is restricted to pyramidal and granular cells”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [69] source

      The Discussion (page unavailable in our copy) says that cells of all cell types expressed GFP after transduction with any of the analyzed serotypes, which include AAV2. That directly contradicts the claim that AAV2 transduction is restricted to pyramidal and granular cells. (LLM, conf=0.90)

      Checked by a reasoning model — may be wrong.

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  • Premisecitation
    § Discussion

    In the study by Hinderer et al., comparison of intracisternal and intraventricular delivery of AAV9-GUSB to mucopolysaccharidosis-afflicted canines found that the intraventricular route led to inflammation and development of encephalitis.

    “comparison of intracisternal and intraventricular delivery of AAV9-GUSB (1.8 × 1013 gc, 1 mL) to mucopolysaccharidosis-afflicted canines found that the intraventricular route lead to inflammation and development of encephalitis”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [95] source

      The Results report encephalitis in dogs given intraventricular AAV9-GFP, not AAV9-GUSB. The dog given intraventricular AAV9-GUSB had no clinical abnormalities or generalized encephalitis, although histology found a localized lesion with lymphocytic infiltration beside the needle track. The claim conflates the two experiments. (LLM, conf=0.91)

      Checked by a reasoning model — may be wrong.

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  • Premisecitation
    § Discussion

    After intrathecal delivery, vectors stay predominantly in the lower spine.

    “The vectors stay predominantly in the lower spine in intrathecal delivery administrations.”
    Quote in the paperNot a substantial claim3 of 4 sources checked
    • cites [90] Pleticha J, 2014, Mol Pain source

      The section on vector-delivery procedures (page unavailable) describes intrathecal delivery into lumbar cerebrospinal fluid, but it does not say the vectors stay predominantly in the lower spine. The off-target biodistribution section (page unavailable) notes limited brain penetration for AAV8 in rodents but potentially widespread CNS transduction for intrathecal AAV9, so the claimed distribution cannot be generalized across vectors. (LLM, conf=0.76)

      Experimental — accuracy not yet measured
    • cites [91] source

      The discussion of intrathecal delivery (section labeled References; page unavailable) says that rAAV serotypes have been administered by that route, but does not describe where the vectors remain afterward. Searches for lower-spine localization and lumbar distribution found no passage addressing the claim. (LLM, conf=0.74)

      Experimental — accuracy not yet measured
    • cites [92] source

      The Results section on AAV9 injection into the cerebrospinal fluid reports extensive motor-neuron transduction at all levels of the spinal cord after intrathecal injection at L5, not confinement to the lower spine. The Materials and Methods section also reports confirmed rostral and caudal intrathecal flow. Page numbers are not available in our copy. (LLM, conf=0.85)

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    • cites [93] source
  • Classified as probably not a substantial claim. 42
  • May combine two claims. 35
  • The quote only partly states this claim. 2

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    Premisecitation
    § Discussion

    The AAV gene packaging size is limited to a maximum of 5.0 kb.

    “Although the gene packaging size is limited (maximum 5.0 kb), typically the relevant gene coding sequences can be easily packaged for CNS delivery.”
    Quote in the paperNot a substantial claim2 of 2 sources checked
    • cites [52] source

      Sections 1 and 2 confirm that AAV packaging capacity is limited, but they give a maximum of about 4.5 kb, not 5.0 kb. Section 2 further specifies 4.5 kb for single-stranded vectors and 2.4 kb for self-complementary vectors. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
    • cites [67] source

      The Discussion states that AAV packaged vector genomes as large as 6 kb with similar efficiency, contrary to the claimed 5.0-kb maximum. The paper distinguishes packaging capacity from the reduced infectivity of some larger-genome vectors. (LLM, conf=0.90)

      Checked by a reasoning model — may be wrong.

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  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation
    § Discussion

    AAV5 transduces only granular cells.

    “AAV5 transduces only granular cells”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [69] source

      The Results section, “Analysis of cell-type tropism for various serotypes” (page unavailable), reports GFP expression in every cell type analyzed with each injected serotype, including rAAV5—not only granular cells. The Discussion also reports rAAV5 transduction of excitatory neurons in the lateral entorhinal cortex. (LLM, conf=0.91)

      Checked by a reasoning model — may be wrong.

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  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation
    § Discussion

    Use of intrathecal delivery for gene therapy vectors has been limited to studies involving spinal cord and peripheral nerve disease.

    “Use of intrathecal delivery for gene therapy vectors has been limited to studies involving spinal cord and peripheral nerve disease.”
    Quote in the paperNot a substantial claim3 of 4 sources checked
    • cites [90] Pleticha J, 2014, Mol Pain source

      In “AAV serotypes and off-target biodistribution” (page unavailable), the paper says intrathecal AAV9 was in preclinical development for mucopolysaccharidosis IIIA as well as giant axonal neuropathy, and describes its transduction of both the central and peripheral nervous systems. The References section identifies a study of intracerebrospinal-fluid gene therapy for whole-body correction of mucopolysaccharidosis IIIA. Thus, the paper does not limit studies of this delivery route to spinal cord and peripheral nerve disease. (LLM, conf=0.86)

      Checked by a reasoning model — may be wrong.

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    • cites [91] source

      The passage discussing PNS gene therapy (indexed under References; page unavailable) identifies intrathecal delivery of rAAV vectors among techniques studied for peripheral sensory conditions, including neuropathic pain. It does not say that intrathecal vector delivery has been limited to spinal cord and peripheral nerve disease studies; that restriction is unsupported. (LLM, conf=0.82)

      Experimental — accuracy not yet measured
    • cites [92] source

      The Results section, “AAV9 injection into the CSF produces transgene expression in the brain” (page unavailable), reports examining brain expression after intrathecal or cisternal vector injection in piglets. The paper therefore does not confine its investigation of intrathecal gene delivery to spinal cord and peripheral nerve disease, as the claim says. (LLM, conf=0.81)

      Checked by a reasoning model — may be wrong.

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    • cites [93] source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation
    § Introduction

    APOE4 homozygotes have an earlier age of onset for developing Alzheimer's disease (approximately 5 years for each APOE4 allele compared to APOE3 homozygotes).

    “as well as an earlier age of onset for developing the disease (approximately 5 years for each APOE4 allele compared to APOE3 homozygotes).6,9,10”
    Quote in the paperNot a substantial claim2 of 3 sources checked
    • cites [6] Genin E, 2011, Mol Psychiatry source

      The Results (page not provided) compare APOE4 genotypes with APOE3 homozygotes across age-of-onset groups, and the paper says APOE4 is a risk factor for early-onset Alzheimer’s disease. It does not report an onset approximately five years earlier for each APOE4 allele. (LLM, conf=0.83)

      Experimental — accuracy not yet measured
    • cites [9] source
    • cites [10] Sando SB, 2008, BMC Neurol source

      The Discussion reports earlier onset of late-onset Alzheimer’s disease with each APOE ε4 allele, but estimates about three years per allele, not five. The Results also report no significant effect on age at onset in early-onset Alzheimer’s disease. (LLM, conf=0.90)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation
    § Introduction

    There are three common APOE alleles (E2, E3, and E4), each encoding APOE isoforms expressed primarily in the liver and brain.

    “There are three common APOE alleles (E2, E3, and E4), each encoding APOE isoforms expressed primarily in the liver and brain.7,8”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [7] source
    • cites [8] source

  • May combine two claims.

    Premisecitation
    § Introduction

    Currently approved drugs do little to limit Alzheimer's disease progression, and no preventive therapies are available.

    “Currently approved drugs do little to limit disease progression, and no preventive therapies are available.3,4”
    Quote in the paperSubstantial claim2 of 2 sources checked

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductcitation
    § Methods

    The values from the control animal in this study and controls in previous studies with African Green monkeys were used to calculate normal ranges and establish upper and lower limits of normal African Green monkey values for comparisons of pre- and post-surgery blood/serum parameters.

    “The values from the control animal in this study and controls in previous studies with African Green monkeys were used to calculate normal ranges (total 65 blood samples from 29 individual male NHPs) and establish the upper and lower limits of normal African Green monkey values for comparisons of pre- and post-surgery blood/serum parameters.31,35”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [31] source

      Split into 2 atoms — 1 confirmed, 1 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

      Experimental — accuracy not yet measured
    • cites [35] Sondhi D, 2016, Mol Ther source

  • Classified as probably not a substantial claim.

    Study design and conductreasoning
    § Methods

    Statistical comparisons were considered significant if p < 0.01 because of the small sample size (n = 3/group) and daily variations in cell numbers and serum chemistries.

    “Due to the small sample size (n = 3/group) and daily variations in cell numbers and serum chemistries, statistical comparisons were considered to be significant if p < 0.01.31,37,38”
    Quote in the paperSubstantial claim1 of 3 sources checked
    • cites [31] source

      The Results (page unavailable) report statistical comparisons of serum chemistry and blood-count measurements. They describe n=2 monkeys per route, except n=1 for the intraarterial route, rather than n=3 per group. The passages do not state a p<0.01 significance threshold or attribute one to daily variation in cell numbers and serum chemistries. (LLM, conf=0.86)

      Experimental — accuracy not yet measured
    • cites [37] source
    • cites [38] source

  • May combine two claims.

    Premisecitation
    § Introduction

    Studies with a lentiviral vector expressing APOE2 delivered directly to the hippocampus of a transgenic Alzheimer's disease mouse established a robust protective effect of the APOE2 allele on Alzheimer's disease risk, with an observed rapid, significant reduction in brain amyloid burden and neuritic plaques.

    “Studies with a lentiviral vector expressing APOE2 delivered directly to the hippocampus of a transgenic AD mouse established a robust protective effect of the APOE2 allele on AD risk, with an observed rapid, significant reduction in brain amyloid burden and neuritic plaques.23”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [23] source

      Split into 2 atoms — 0 confirmed, 2 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

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  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation
    § Discussion

    Targeting the large cerebral ventricles (intraventricular route) in the frontal lobe is an easy surgical task and is commonly used to deliver drugs to the CNS.

    “Targeting the large cerebral ventricles (intraventricular route) in the frontal lobe of the brain is an easy surgical task, and is commonly used to deliver drugs to the CNS.”
    Quote in the paperNot a substantial claim3 of 4 sources checked
    • cites [85] source

      The Experimental Procedures (page not provided) describe stereotaxic injections into rats’ lateral ventricles, and the Discussion describes prior intraventricular delivery of IGF-1. These passages support use of the route to deliver a therapeutic agent, but do not establish that targeting ventricles in the frontal lobe is an easy surgical task or that the route is commonly used for drugs generally. (LLM, conf=0.84)

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    • cites [86] Pardridge WM, 2016, Expert Opin Drug Deliv source
    • cites [87] source

      The Abstract and Discussion say that delivery into the brain ventricles is commonly used to administer peptides and pharmacological agents to the CNS. They do not describe the ventricles as being in the frontal lobe or targeting them as an easy surgical task. The Abstract instead notes technical drawbacks and says that installing and manipulating an ICV pump requires complex surgery. (LLM, conf=0.88)

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    • cites [88] source

      Materials and Methods (rhTPP1 Formulation and Administration; page unavailable) describes a catheter placed in a lateral ventricle and used to infuse treatment into the CNS. It does not say the ventricle was targeted in the frontal lobe, that placement was an easy surgical task, or that this route is commonly used for CNS drug delivery. (LLM, conf=0.85)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation
    § Discussion

    Convection-enhanced delivery increases the vector volume that can be delivered to the target site and enhances cell transduction in the targeted CNS substructure.

    “This has the advantage of increased vector volume that can be delivered to the target site, which enhances cell transduction in the targeted CNS substructure”
    Quote in the paperNot a substantial claim2 of 3 sources checked
    • cites [78] source

      The Introduction (page unavailable) says convection-enhanced delivery distributes vector at higher concentrations over a larger area than diffusion alone. The Results, ‘Distribution of hrGFP within the brain’ (page unavailable), report transduction volumes larger than the infused volumes. Neither passage establishes that CED increases the amount of vector that can be delivered to a target site; the claim appears to conflate delivered volume with distribution or transduction volume. (LLM, conf=0.84)

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    • cites [79] source

      The Introduction describes CED as a means of distributing viral vectors to brain targets, and Methods §2.1 reports vector co-infusions of 30–300 μL. The paper does not show that CED increases the volume of vector that can be delivered relative to another method or that a larger volume enhances cell transduction in the targeted CNS structure. (LLM, conf=0.84)

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    • cites [80] source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation
    § Discussion

    The AAV serotypes most commonly used for clinical trials to date are AAV5, AAV9, and AAVrh.10.

    “Of these AAV serotypes, the most commonly used for clinical trials to date are AAV5, AAV9, and AAVrh.10.”
    Quote in the paperNot a substantial claim3 of 4 sources checked
    • cites [52] source

      Section 4.1 identifies AAV9 and AAVrh10 as capsids used in more recent clinical trials. It does not identify AAV5 as commonly used in trials or establish that these three are the most commonly used serotypes; Section 3.1 discusses AAV5's cell-transduction pattern instead. The paper also says AAV2 was used in all first-generation trials. (LLM, conf=0.86)

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    • cites [56] source

      The Lysosomal storage disorders section describes clinical trials using AAV5, AAV9, and AAVrh.10. But neither that section nor the Introduction establishes that these are the most commonly used serotypes in clinical trials; the Introduction also describes AAV2 trials. The source supports their clinical use, not the claimed ranking. (LLM, conf=0.87)

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    • cites [58] source
    • cites [71] source

      The Overview of Adeno-associated Virus-mediated CNS Gene Therapy discusses AAV5, AAV9, and AAVrh.10, and Lessons Learned and Path Forward describes an AAVrh.10 clinical trial. But the paper does not say these are the most commonly used serotypes in clinical trials; its discussion of AAV5 concerns earlier studies, and it mentions AAV9 as a discovered serotype, not as a clinical-trial vector. (LLM, conf=0.85)

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  • Classified as probably not a substantial claim. May combine two claims.

    Premisecitation
    § Discussion

    AAV vector administration to the CNS has an excellent safety and efficacy profile.

    “AAV vector administration to the CNS has an excellent safety and efficacy profile.”
    Quote in the paperSubstantial claim4 of 10 sources checked
    • cites [52] source

      Section 2 describes AAV vectors as close to ideal for CNS gene therapy, citing low toxicity and mild immunogenicity. But section 4.1 reports that clinical trials were less effective, with no significant improvement in one trial and only minor improvement in another. The paper supports a favorable safety profile, but not a generally excellent clinical efficacy profile. (LLM, conf=0.87)

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    • cites [53] source

      Section 5.1 describes AAV vectors as suitable for brain gene delivery because of their low immunogenicity and reports effective transduction. Section 7 reports that an AAV2 trial was safe and well tolerated, but says its efficacy was still being evaluated; the paper also reports AAV9 immune activation and possible neurotoxicity in Section 5.1. These qualifications do not support an unqualified claim of an excellent safety and efficacy profile for CNS AAV administration. (LLM, conf=0.88)

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    • cites [55] source
    • cites [56] source
    • cites [57] source
    • cites [58] source
    • cites [59] source

      The Abstract (page not supplied) reports no long-term adverse events related to AAV2 and preliminary benefits in 13 patients with Canavan disease. The Discussion says the positive clinical and imaging findings need validation in a larger trial. These findings do not establish an excellent safety and efficacy profile for AAV administration to the CNS generally. (LLM, conf=0.88)

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    • cites [60] source
    • cites [61] source
    • cites [62] source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation
    § Discussion

    AAV vector-mediated gene therapy has become a preferred method for delivering therapeutic genes to the CNS.

    “AAV vector-mediated gene therapy has become a preferred method for delivering therapeutic genes to the CNS.”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [52] source
    • cites [66] Golebiowski D, 2015 source

  • May combine two claims.

    Premisecitation
    § Discussion

    In AD, amyloid deposition spreads and the disease pathogenesis progressively involves a broad region of the brain.

    “the amyloid deposition spreads, and the disease pathogenesis progressively involves a broad region of the brain”
    Quote in the paperSubstantial claim3 of 3 sources checked
    • cites [20] Reiman EM, 2009, Proc Natl Acad Sci U S A source

      The Discussion (page unavailable) reports fibrillar amyloid-β burden across several brain regions associated with AD, supporting the claim that deposition involves a broad region of the brain. But the paper does not establish that deposition spreads over time or that disease pathogenesis progressively involves more regions; the Discussion notes the absence of longitudinal amyloid data. (LLM, conf=0.85)

      Experimental — accuracy not yet measured
    • cites [43] source

      The Discussion (page unavailable) describes amyloid accumulation in several cortical regions, supporting the claim that pathology involves multiple brain regions. It does not establish that deposition spreads progressively; the Discussion’s limitations say the cross-sectional study cannot determine whether biomarker changes are ongoing. (LLM, conf=0.84)

      Experimental — accuracy not yet measured
    • cites [44] Tang X, 2016, Magn Reson Imaging source

      The Introduction describes AD as a progressive neurodegenerative disorder, and the Results report abnormalities in the hippocampus and amygdala. But the paper’s passages do not say that amyloid deposition spreads or that pathology progressively extends across a broad region of the brain; the findings concern specific structures rather than brain-wide progression. (LLM, conf=0.82)

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  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation
    § Discussion

    Intranasal delivery of AAV9 via the nasal cavity in mice for mucopolysaccharidosis I resulted in widespread detection of transgene activity across the CNS.

    “an additional non-surgical route—intranasal—has been tested delivering AAV9 via the nasal cavity in mice for mucopolysaccharidosis I, resulting in widespread detection of the transgene activity across the CNS”
    Quote in the paperNot a substantial claim1 of 1 sources checked

  • May combine two claims.

    Premisecitation
    § Discussion

    The hippocampal region is important to short-term memory loss in AD and is the earliest region involved in the progression of the disease.

    “the hippocampal region is important to short-term memory loss in AD and is the earliest region involved in the progression of the disease”
    Quote in the paperSubstantial claim4 of 4 sources checked
    • cites [39] Gomez-Isla T, 1996, J Neurosci source

      The Discussion (page not supplied) links vulnerability of the hippocampal CA1 region to memory impairment in AD. But the paper identifies marked entorhinal-cortex changes in very mild AD; it does not establish that the hippocampal region is the earliest region involved or specifically attribute short-term memory loss to it. (LLM, conf=0.84)

      Experimental — accuracy not yet measured
    • cites [40] source

      The Results (LEC versus MEC dysfunction; page unavailable) link impaired delayed retention in early Alzheimer’s disease to the lateral entorhinal cortex, and the Discussion links that task to hippocampal-dependent memory. But the paper identifies the lateral entorhinal cortex—not the hippocampus itself—as the primary early site of dysfunction, so it does not support calling the hippocampus the earliest region involved. (LLM, conf=0.87)

      Experimental — accuracy not yet measured
    • cites [41] source

      The Discussion and Image analysis sections report early hippocampal atrophy in people with MCI who later developed AD, but identify several other medial temporal regions with early loss; they do not establish the hippocampus as the single earliest region. The passages do not link hippocampal atrophy specifically to short-term memory loss. (LLM, conf=0.87)

      Experimental — accuracy not yet measured
    • cites [42] Yang X, 2018, Mol Psychiatry source

      The Introduction and Results link hippocampal CA1 circuits to spatial-memory impairment in AD mice, supporting a role for the hippocampal region in memory loss. They do not identify the impairment as short-term memory loss. The Introduction instead identifies entorhinal-cortex neurons as particularly vulnerable early in AD; it does not say the hippocampus is the earliest region involved. (LLM, conf=0.86)

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  • May combine two claims.

    Premisecitation
    § Discussion

    The olfactory bulb, which connects to the entorhinal cortex, is directly affected by changes in the perforant pathway and is one of the earliest pathological changes in AD.

    “the connection to the entorhinal cortex, the olfactory bulb, is directly affected by changes in the perforant pathway, and one of the earliest pathological changes in AD”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [43] source

      The Discussion (page unavailable) says that brain regions involved in olfaction are vulnerable to AD pathology and reports reduced entorhinal cortical thickness. It does not say that the olfactory bulb is directly affected by perforant-pathway changes or that this is among the earliest pathological changes in AD. (LLM, conf=0.82)

      Experimental — accuracy not yet measured
    • cites [49] source

  • May combine two claims.

    Findingown data
    § Results

    For the intraventricular route, 51.5% of cubes had protein levels above threshold compared to 3.0% of control cubes.

    “The same pattern was observed for the intraventricular route (treated, DNA 90.0% cubes, control 3.9% cubes; mRNA treated 86.0% cubes, control 2.9% cubes; and protein 51.5% cubes, control 3.0% cubes; Table 3).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data
    § Results

    Histopathological examination of the brain left frontal lobes from the dual-route NHPs revealed focal lesions in the gray matter with minor histiocytic infiltrate and hemosiderosis, and multifocal gliosis with histiocytic infiltrate, hemosiderosis, spongiosis, and vascular hyperplasia in the underlying white matter.

    “Histopathological examination of the brain left frontal lobes from the dual-route NHPs (NHP-10–NHP-12) revealed focal lesions in the gray matter with minor histiocytic infiltrate and hemosiderosis in the gray matter (Supplementary Fig. S7A–F) and multifocal gliosis with histiocytic infiltrate, hemosiderosis, spongiosis, and vascular hyperplasia in the underlying white matter (Supplementary Fig. S7”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Results

    There was heavy staining of ependymal cells of the choroid plexus in the ventricles, as well as in areas around the frontal and mid-brain, including the hippocampal region, and areas around the posterior of the brain and spinal cord.

    “There was heavy staining of the ependymal cells of the choroid plexus in the ventricles, as expected due to the routes of delivery into the CSF (Supplementary Figs. S3–S5) but also in areas around the frontal and mid-brain, including the hippocampal region, as well as areas around the posterior of the brain and spinal cord.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data
    § Results

    For the intraventricular route, 90.0% of cubes had vector DNA levels above threshold compared to 3.9% of control cubes.

    “The same pattern was observed for the intraventricular route (treated, DNA 90.0% cubes, control 3.9% cubes; mRNA treated 86.0% cubes, control 2.9% cubes; and protein 51.5% cubes, control 3.0% cubes; Table 3).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data
    § Results

    For both intracisternal and intraventricular routes, greater than baseline levels of vector APOE2-HA copies, mRNA transgenes, and ApoE2-HA protein were observed in most cubes throughout the CNS, as well as in the hippocampal regions.

    “For both the intracisternal and the intraventricular routes, for each parameter, greater than baseline levels of vector APOE2-HA copies (Fig. 2A and B), mRNA transgenes (Fig. 2C and D), and ApoE2-HA protein (Fig. 2E and F) were observed in most cubes throughout the CNS, as well as in the hippocampal regions.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The HA tag does not alter the function or distribution of ApoE2.
    • Rests on an assumption: The anti-HA antibody specifically detects vector-derived ApoE2-HA without cross-reactivity to endogenous ApoE2.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingown data
    § Results

    For the intracisternal vector-treated animals, one of three NHPs had an elevated heart rate (days 7 and 14), and one of three NHPs had an elevated respiratory rate (days 7 and 28).

    “For the intracisternal vector-treated animals, one of three NHPs had an elevated heart rate (days 7 and 14), and one of three NHPs had an elevated respiratory rate (days 7 and 28).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Results

    Pairwise statistical comparisons between treated NHPs and non-treated sham controls showed very few parameters with significant p-values (p < 0.01), none of which had clinical significance.

    “Pairwise statistical comparisons between the treated NHPs and non-treated sham controls showed very few parameters with significant p-values (p < 0.01), none of which had clinical significance.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Results

    Similar findings lacked differences for in-life parameters (total body weight, body temperature, heart and respiratory rates), with a few scattered outliers, with nothing linked to the vector.

    “Similar findings lacked differences for in-life parameters (total body weight, body temperature, heart and respiratory rates; not shown), with a few scattered outliers, with nothing linked to the vector.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Results

    No differences were noted for the necropsy weights between the dual-route (intraventricular plus intracisternal) and PBS-treated controls, other than smaller hearts in the smaller monkeys.

    “No differences were noted for the necropsy weights between the dual-route (intraventricular plus intracisternal) and PBS-treated controls, other than smaller hearts in the smaller monkeys (not shown).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data
    § Results

    Rare outlier values were observed over the course of the study for a small number of hematologic and serum chemistry parameters for both treated animals and controls.

    “When compared to the historic ranges, there were rare outlier values observed over the course of the study for a small number of hematologic and serum chemistry parameters for both treated animals and controls.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Results

    Total anti-AAVrh.10 antibody titers were significantly different between treated and non-treated groups at day 28 and 56 for intracisternal (p < 0.01) and intraventricular (p < 0.04) routes, with no significant difference between intracisternal and intraventricular routes (p > 0.06).

    “Statistical comparisons between the NHP cohorts showed significance between treated and non-treated groups comparing day 28 and 56 titers for each group by the Student's t-test (total antibody titers, intracisternal vs. non-treated, p < 0.01; intraventricular vs. non-treated, p < 0.04, intracisternal vs. intraventricular, p > 0.06; Fig. 5A;”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Results

    Neutralizing anti-AAVrh.10 antibody titers were significantly different between treated and non-treated groups for intracisternal (p < 0.02) and intraventricular (p < 0.03) routes, with no significant difference between intracisternal and intraventricular routes (p > 0.06).

    “neutralizing titers, intracisternal vs. non-treated, p < 0.02; intraventricular vs. non-treated, p < 0.03; intracisternal vs. intraventricular, p > 0.06; Fig. 5B).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Results

    Specific significant differences between treated and control animals were observed for globulin and albumin/globulin ratio (intracisternal), WBCs and reticulocytes (intraventricular), and RBCs and hematocrit (dual intraventricular/intracisternal); none was vector related.

    “For the intracisternal vector-treated treated animals, there was a significant difference between treated and control animals for globulin (day 28) and albumin/globulin ratio (day 28). For the intraventricular vector-treated animals, there was significant difference between treated and control animals for WBCs (day 0) and reticulocytes (day 28). For the dual intraventricular/intracisternal vector”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data
    § Results

    For the dual intraventricular/intracisternal vector-treated animals, one of three NHPs had an elevated heart rate (days 7 and 14).

    “For the dual intraventricular/intracisternal vector-treated animals, one of three NHPs had an elevated heart rate (days 7 and 14).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Results

    MRI at 0 and 8 weeks showed no visual pathology around the administration sites other than thin holes from catheters, and no inflammation or pathologic abscesses were discovered.

    “No visual pathology was noted around the administration sites other than thin holes from catheters. No inflammation or pathologic abscesses were discovered on the MRI series.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data
    § Discussion

    In the present NHP study, the direct hippocampal, intracisternal, and intraventricular routes all resulted in effective expression of ApoE2-HA in the hippocampal and entorhinal cortex region and did so safely.

    “The data demonstrate that the direct hippocampal, intracisternal, and intraventricular routes all result in effective expression of ApoE2-HA in the hippocampal and entorhinal cortex region, the regions effected the earliest in AD,39–42 and do so safely.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data
    § Discussion

    In the present NHP study, both the intracisternal and intraventricular routes resulted not only in intrahippocampal expression but also in widespread expression throughout the brain.

    “Both the intracisternal and intraventricular routes result not only in intrahippocampal expression, but also in widespread expression throughout the brain.”
    Quote in the paperSubstantial claim

  • The quote only partly states this claim.

    Findingown data
    § Discussion

    In the present NHP study, the vector-administered groups did not differ from the sham control in any hematologic, serum chemistry, or behavior parameter.

    “The vector-administered groups did not differ from the sham control in any parameter.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data
    § Discussion

    In the present NHP study, the intracisternal and intraventricular routes were equivalent in vector, APOE2 mRNA, and ApoE2-HA protein, and both routes were equally safe.

    “the intracisternal and intraventricular routes are equivalent in vector, APOE2 mRNA, and ApoE2-HA protein, and both routes are equally safe”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductnone given
    § Methods

    All experiments were conducted in an AAALAC-accredited facility and approved by the Institutional Animal Care and Use Committee of Weill Cornell Medical College.

    “All experiments were conducted in an AAALAC-accredited facility and approved by the Institutional Animal Care and Use Committee of Weill Cornell Medical College (New York, NY).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data
    § Methods

    Histopathologic changes were examined by a board-certified veterinary pathologist.

    “stained with H&E, and examined by a board-certified veterinary pathologist, and histopathologic changes were recorded.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). The quote only partly states this claim.

    Study design and conductnone given
    § Methods

    Samples of the vector were taken for quality control assays that evaluated the presence of adventitious agents.

    “Samples of the CVL were taken for quality control assays that evaluated the presence of adventitious agents.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data
    § Methods

    MRI and CT images were fused to generate a 3D map of the brain from which stereotaxic coordinates were determined to guide catheter placement accurately.

    “The MRI and CT images were fused to generate a three-dimensional (3D) map of the brain from which the stereotaxic coordinates were determined using Brainlab iPlan Stereotaxy 3.0 software”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data
    § Methods

    The final purified AAVrh.10hAPOE2-HA product was characterized with assays for identity, potency, and purity.

    “The final purified product was characterized with assays for measures of identity, potency, and purity.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given
    § Methods

    Samples that failed amplification were re-extracted and retested.

    “Samples that failed amplification were re-extracted and retested.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given
    § Methods

    All assays were performed with a standard curve based on a hAPOE2-HA plasmid run in triplicate.

    “All assays were performed with a standard curve based on a hAPOE2-HA plasmid (108–101 gc) run in triplicate.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given
    § Methods

    The AAVrh.10hAPOE2-HA vector was produced under current Good Manufacturing Practice conditions.

    “The AAVrh.10hAPOE2-HA vector was produced under current Good Manufacturing Practice conditions at the Belfer Gene Therapy Core Facility”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data
    § Methods

    Necropsy was performed by a board-certified veterinary pathologist.

    “All organs were examined grossly during necropsy performed by a board-certified veterinary pathologist”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationown data
    § Results

    These histopathological findings were compatible with a needle tract used to deliver the AAV vector in the intraventricular route and comparable to that observed in PBS-treated animals.

    “These findings were compatible with a needle tract used to deliver the AAV vector in the intraventricular route and comparable to that observed in PBS-treated animals (NHP-13–NHP-14; Supplementary Fig. S8A–D).”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductnone given
    § Methods

    All nonhuman primates used were quarantined for a 3-month period after arrival and were deemed in good health and suitable for experimental use.

    “All NHPs used were quarantined for a 3-month period after arrival and were deemed in good health and suitable for experimental use.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given
    § Methods

    All slides were evaluated by a board-certified pathologist.

    “All slides were evaluated by a board-certified pathologist, and observations were recorded.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given
    § Methods

    Matching IgG control slides were used to remove background from the .tif images by setting negative controls as masks.

    “Matching IgG control slides were used to remove the background from the .tif images, by setting the negative controls as masks in Adobe PhotoShop.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data
    § Results

    NHP behavior was analyzed by blinded videotape.

    “Blinded videotape analysis of NHP behavior before surgery and after administration showed no discernible neurological differences in any of the routes tested (Fig. 6).”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Study design and conductreasoning
    § Results

    A HA peptide tag was added to the 3′ terminus of the hAPOE2 vector construct to distinguish vector-derived APOE2 from endogenous primate APOE2 in immunohistochemical and quantitative assays.

    “To distinguish the vector-derived APOE2 from endogenous primate APOE2 in immunohistochemical and quantitative assays, a HA peptide tag was added to the 3′ terminus of hAPOE2 vector construct (AAVrh.10hAPOE2-HA).”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The HA tag does not alter the function or distribution of ApoE2.

  • Classified as probably not a substantial claim.

    Study design and conductown data
    § Methods

    Behavioral assessments were scored by observers (n = 2) blinded to treatment and route.

    “Behaviors were scored by observers (n = 2) blinded to treatment and route from the videotape sessions”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given
    § Methods

    Each sample was analyzed in duplicate.

    “Each sample was analyzed in duplicate.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisenone given
    § Discussion

    The intraparenchymal route requires invasive surgery with weeks of postoperative recovery.

    “the requirement for invasive surgery with weeks of postoperative recovery”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisenone given
    § Discussion

    The most common route for vector-mediated delivery of a therapeutic transgene to the CNS is direct administration to the brain parenchyma (intraparenchymal route).

    “The most common route is direct administration to the brain parenchyma (intraparenchymal route)”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationcitation
    § Results

    The elevated ALT, AST, and LDH at early time points were most likely surgery and anesthesia related, and all resolved by day 56.

    “The elevated ALT, AST, and LDH at early time points were most likely surgery and anesthesia related,51 and all of these resolved (day 56; Supplementary Fig. S11E, F, and G).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [51] Woodward RA, 1997, Contemp Top Lab Anim Sci

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisenone given
    § Discussion

    The intraparenchymal route has disadvantages including limited vector delivery amounts and volumes and limited spread of the vector in confined space.

    “there are disadvantages, including limited vector delivery amounts and volumes, limited spread of the vector in confined space”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation
    § Discussion

    AAV4 is astrocyte and ependymal cell specific.

    “AAV4 is astrocyte and ependymal cell specific”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [70] source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisereasoning
    § Discussion

    The advantage of the intraparenchymal route is directed gene delivery to specific targeted brain regions.

    “The advantage of this route is the directed gene delivery to specific targeted brain regions.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisenone given
    § Discussion

    Convection-enhanced delivery carries possible localized trauma from the surgical intervention and increased pressure of fluid volume due to vector delivery in a confined space.

    “the CED strategy has associated localized trauma possible from the surgical intervention and increased pressure of fluid volume due to vector delivery in a confined space”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationown data
    § Discussion

    Gene therapy with AAVrh.10hAPOE2 generates localized ApoE2 expression and secretion across the width and breadth of the CNS, successfully targeting the AD-associated regions.

    “demonstrating that gene therapy with AAVrh.10hAPOE2 generates localized ApoE2 expression and secretion across width and breadth of the CNS, resulting in successful targeting the AD-associated regions”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationreasoning
    § Discussion

    Because the intracisternal route is the least invasive, it is the best route for APOE2 gene therapy to treat APOE4 homozygotes.

    “it is concluded that since the intracisternal route is the least invasive, it is the choice as the best route for APOE2 gene therapy to treat APOE4 homozygotes”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationown data
    § Discussion

    Intracisternal delivery in NHPs is safe and results in widespread expression of ApoE2, laying the framework for a clinical trial.

    “intracisternal delivery in NHPs is safe and results in widespread expression of ApoE2, laying the framework for a clinical trial”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: ApoE2 produced in the CNS is not toxic, so it does not matter where in the CNS it is produced as long as it reaches the CSF.
    • Rests on an assumption: The safety and widespread ApoE2 expression observed in NHPs will translate to humans.

  • May combine two claims.

    Interpretationreasoning
    § Discussion

    If these levels of ApoE2 can be achieved in humans, this should be therapeutic, at a minimum converting an APOE4 homozygote to an E4/E2 heterozygote.

    “If these levels of ApoE2 can be achieved in humans, this should be therapeutic, at a minimum converting an APOE4 homozygote to an E4/E2 heterozygote.”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: ApoE2 produced in the CNS is not toxic, so it does not matter where in the CNS it is produced as long as it reaches the CSF.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given
    § Discussion

    Behavior parameters in the present study were assessed by blinded videotape analysis across all routes.

    “blinded videotape analysis of behavior parameters were assessed over the course of the study with all routes”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation
    § Discussion

    In one study, vector distribution after intrathecal administration in NHPs was improved when the animal was placed in the Trendelenburg tilted position during infusion, leading to superior brain expression, especially in the brain stem.

    “vector distribution following intrathecal vector administration in NHPs was improved in one study if the animal was placed in the Trendelenburg tilted position during the intrathecal infusion, which led to superior expression in the brain, especially in the brain stem”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [94] source

  • May combine two claims.

    Interpretationreasoning
    § Discussion

    Administration to the CSF via the intracisternal route is sufficient and the least invasive.

    “indicating that administration to the CSF via this route is sufficient and the least invasive”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: The safety and widespread ApoE2 expression observed in NHPs will translate to humans.

  • Probably not a substantial claim: may not pass S4 (based).

    Premisenone given
    § Discussion

    ApoE2 is a secreted protein.

    “ApoE2 is a secreted protein”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation
    § Discussion

    Loss of visual recognition is a characteristic pathology associated with AD.

    “the loss of visual recognition is a characteristic pathology associated with AD”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [50] source
70 of 70

  • The paper relies on this without support.

    The nonhuman primate CNS is a valid model for predicting APOE2 gene therapy distribution and safety in the human CNS.

    “To assess the CNS distribution and safety of APOE2 gene therapy for AD in a large-animal model”

  • The paper relies on this without support.

    The HA tag on human APOE2 does not alter the function, distribution, or safety of APOE2.

    “In order to differentiate vector-mediated expression of APOE2 transgene and protein over the endogenous APOE2 in the NHP brain, the human APOE2 was HA-tagged on the 3′ terminus.”

  • The paper relies on this without support.

    Two months after vector administration is sufficient to assess the persistence and distribution of APOE2 expression relevant to clinical therapy.

    “the expression of APOE2 in the CNS was evaluated 2 months following vector administration”

  • The paper relies on this without support.

    The doses of AAVrh.10hAPOE2-HA used in nonhuman primates are relevant to potential human therapeutic doses.

    “5 × 1012 genome copies (gc; 0.7–1.2 × 1012 gc/kg) of AAVrh.10hAPOE2-HA”

  • The paper relies on this without support.

    The HA tag does not alter the function or distribution of ApoE2.

    “To distinguish the vector-derived APOE2 from endogenous primate APOE2 in immunohistochemical and quantitative assays, a HA peptide tag was added to the 3′ terminus of hAPOE2 vector construct (AAVrh.10hAPOE2-HA).”

  • The paper relies on this without support.

    The NHP CNS distribution and safety results are predictive of outcomes in humans.

    “To translate this therapy to the clinic, the present study was designed to assess the optimal route of administration and safety of AAVrh.10-mediated delivery of human APOE2 coding sequence to the CNS.”

  • The paper relies on this without support.

    The 8-week post-administration period is sufficient to assess long-term expression and safety.

    “All animals were sacrificed 8 weeks post-vector administration.”

  • The paper relies on this without support.

    The anti-HA antibody specifically detects vector-derived ApoE2-HA without cross-reactivity to endogenous ApoE2.

    “Human ApoE2-HA protein was quantified in AAVrh.10hAPOE2-HA administered brain homogenates and CSF samples using a mouse anti-HA antibody (Sigma–Aldrich) and human ApoE ELISA kit (Abcam, Cambridge, MA).”

  • The authors state this as an assumption.

    ApoE2 produced in the CNS is not toxic, so it does not matter where in the CNS it is produced as long as it reaches the CSF.

    “ApoE2 is a secreted protein, and thus (assuming no toxicity) it should not matter where in the CNS it is produced, as long as it reaches the CSF, which circulates throughout the brain”

  • The paper relies on this without support.

    The safety and widespread ApoE2 expression observed in NHPs will translate to humans.

    “intracisternal delivery in NHPs is safe and results in widespread expression of ApoE2, laying the framework for a clinical trial”
10 of 10

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • The first human trial using AAV to express APOE2 in APOEε4 homozygotes has been initiated, and the reported safety results from this phase I trial are promising despite the small number of participants.

    “the first human trial using AAV to express APOE2 in APOEε4 homozygotes has been initiated, and the reported safety results from this phase I trial are promising despite the small number of participants204”

    From Multifaceted roles of APOE in Alzheimer disease (2024) · cites this paper as [204]

    The Discussion and Results (pages unavailable) describe AAV-mediated APOE2 delivery and safety testing in nonhuman primates as a step toward clinical use. They do not report that a human phase I trial was initiated or provide safety results from human participants; the promising safety findings are from animals. (LLM, conf=0.86)

    Experimental — accuracy not yet measured

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Behavioral assessment schedules disagree

    Minor

    Table 1 includes a two-week behavioral assessment, but the methods specify five assessment time points that omit two weeks.

1 of 1

Cites

Flagged first, then by citations

Research works printed but not linked: 2

  1. Rydenhag B, 2001, Neurosurgery, 49, 51
  2. Woodward RA, 1997, Contemp Top Lab Anim Sci, 36, 55

Cited by

Sorted by citations

Related

Authors
Rosenberg, J. B., Kaplitt, M. G., De, B. P., Chen, A., Flagiello, T., Salami, C., Pey, E., Zhao, L., Ricart Arbona, R. J., Monette, S., Dyke, J. P., Ballon, D. J., Kaminsky, S. M., Sondhi, D., Petsko, G. A., Paul, S. M., & Crystal, R. G.
Affiliations
  • Weill Cornell Medicine (US)
  • Cornell University (US)
  • Center of Comparative Medicine and Pathology, Memorial Sloan Kettering Cancer Center, New York, New York.
  • Laboratory of Comparative Pathology, Memorial Sloan Kettering Cancer Center, The Rockefeller University, Weill Cornell Medical College, New York, New York.
  • Voyager Therapeutics (United States) (US)
ORCID
Venue
Human Gene Therapy Clinical Development
Publisher
SAGE Publications
Published
2018-03
Volume
29
Issue
1
Pages
24-47
ISSN
  • 2324-8637 (ISSN-L)
  • 2324-8645
DOI
10.1089/humc.2017.231
PMC
PMC5870071
OpenAlex
W2792593254
Semantic Scholar
0ac884a047e5992ad0cb4064280ffa639daae6c5
Cited by
169
References
99
Citations by year
2026: 20 · 2025: 27 · 2024: 32 · 2023: 22 · 2022: 17 · 2021: 15 · 2020: 24 · 2019: 11 · 2018: 1
FWCI
7.10
Type
journal article
Language
en
Open access
Licence
www.liebertpub.com/nv/resources-tools/text-and-data-mining-policy/121/ (tdm)
Locations
  • Human Gene Therapy Clinical Development (publishedVersion)
  • PubMed (publishedVersion)
  • Europe PMC (PubMed Central) (submittedVersion)
  • PubMed Central (submittedVersion)
Funders
  • Alzheimer's Drug Discovery Foundation
  • JPB Foundation
  • National Cancer Institute (Grant P30-CA008748, CA008748, Support Grant P30 CA008748, #P30-CA008748)
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Virus-based gene therapy research
  • Health Sciences › Medicine › Physiology › Alzheimer's disease research and treatments
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › RNA Interference and Gene Delivery
Keywords
APOE2, APOE ε4, Alzheimer's disease, gene therapy, central nervous system delivery, nonhuman primate model, vector safety, apolipoprotein E
MeSH terms
Dependovirus, Alzheimer Disease, Animals, Central Nervous System, Chlorocebus aethiops, Genetic Vectors, Humans, Male, Genetic Therapy, Apolipoprotein E4, Apolipoprotein E2, HEK293 Cells

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-11.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-11.

Cited sources are checked by gpt-6-sol.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

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