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Cited by 420Virus-based gene therapy researchRNA Interference and Gene DeliveryParvovirus B19 Infection Studies

Packaging Capacity of Adeno-Associated Virus Serotypes: Impact of Larger Genomes on Infectivity and Postentry Steps

Open access
Grieger, Joshua C., Samulski, Richard J.·2005·Journal of Virology
DOI 10.1128/jvi.79.15.9933-9944.2005PMC PMC1181570
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Abstract

The limited packaging capacity of adeno-associated virus (AAV) precludes the design of vectors for the treatment of diseases associated with larger genes. Autonomous parvoviruses, such as minute virus of mice and B19, while identical in size (25 nm), are known to package larger genomes of 5.1 and 5.6 kb, respectively, compared to AAV genomes of 4.7 kb. One primary difference is the fact that wild-type (wt) AAV utilizes three capsid subunits instead of two to form the virion shell. In this study, we have characterized the packaging capacity of AAV serotypes 1 through 5 with and without the Vp2 subunit. Using reporter transgene cassettes that range in size from 4.4 to 6.0 kb, we determined that serotypes 1 through 5 with and without Vp2 could successfully package, replicate in, and transduce cells. Dot blot analysis established that packaging efficiency was similar for all vector cassettes and that the integrity of encapsidated genomes was intact regardless of size. Although physical characterization determined that virion structures were indistinguishable from wt, transduction experiments determined that all serotype vectors carrying larger genomes (5.3 kb and higher) transduced cells less efficiently (within a log) than AAV encapsidating wt size genomes. This result was not unique to reporter genes and was observed for CFTR vector cassettes ranging in size from 5.1 to 5.9 kb. No apparent advantage in packaging efficiency was observed when Vp2 was present or absent from the virion. Further analysis determined that a postentry step was responsible for the block in infection and specific treatment of cells upon infection with proteasome inhibitors increased transduction of AAV encapsidating larger DNA templates to wt levels, suggesting a preferential degradation of virions encapsidating larger-than-wt genomes. This study illustrates that AAV is capable of packaging and protecting recombinant genomes as large as 6.0 kb but the larger genome-containing virions are preferentially degraded by the proteasome and that this block can be overcome by the addition of proteasome inhibitors.

Verified 2026-10-28 · 1 reference not checked yet

AI snapshot

Written from the paper’s full text.

TL;DR

AAV serotypes 1 through 5, with or without Vp2, can package and protect recombinant genomes as large as 6.0 kb, but vectors carrying genomes larger than about 5.2 kb transduce cells less efficiently. The reduced infectivity is postentry and can be overcome by proteasome inhibition, suggesting preferential proteasome degradation of virions containing larger genomes.

Key findings

  • Packaging efficiency was similar across all vector cassettes and serotypes: dot blot titers for the largest cassettes were 3 × 10⁶ to 9 × 10⁷ viral genomes/μl versus 6 × 10⁶ to 1 × 10⁸ viral genomes/μl for wild-type-size cassettes, with no apparent advantage when Vp2 was absent.
  • AAV serotypes 1 through 5 packaged and protected genomes as large as 6 kb, and alkaline agarose/Southern analysis showed intact encapsidated genomes regardless of size.
  • Transduction was reduced for genomes of 5.3 kb and higher, with CAT assays showing a consistent 3- to 7-fold difference between wild-type-size and K/L genomes; CFTR cassettes from 5.1 to 5.9 kb were also packaged and produced a 450-bp RT-PCR product.
  • The proteasome inhibitor LLnL increased transduction of AAV encapsidating E, K, and L genomes by 1.1-, 2.2-, and 5.7-fold, respectively, at 40 μM, restoring K to wild-type levels and L to near wild-type levels (less than twofold difference).

Methods

  • Recombinant AAV was produced by calcium phosphate triple plasmid transfection in 293 cells using pXR1–pXR5 helper plasmids or Vp2-knockout ACA1–ACA5 plasmids, plus pAVCNst CAT packaging cassettes D through L (4,461–6,019 bp) or CFTR cassettes ranging from 5.1 to 5.9 kb.
  • Vector characterization included dot blot titration, alkaline agarose gel/Southern analysis of extracted virion genomes, Hirt extraction replication assays, electron microscopy, and CAT transduction assays in HeLa or COS-1 cells infected at 500 viral genomes/cell with adenovirus dl309 at an MOI of 5.
  • Additional experiments tested CsCl-, iodixanol-, and FPLC-heparin-purified vectors, temperature stability, CFTR mRNA detection by RT-PCR, and treatment with the proteasome inhibitor LLnL.

Limitations

  • The paper states that the functional relevance of Vp2 remains unresolved, that more sensitive real-time PCR would be needed to directly compare CFTR mRNA levels with and without LLnL, and that further CFTR vector studies are ongoing but beyond the scope of the study.
  • The paper notes that fitness of larger-genome viruses was not tested because it is not relevant for vector production, which involves only one round of infection rather than cycling.
  • Evident from the text: many packaging and transduction screens used crude lysates and small-scale productions, and the authors note preparation-to-preparation variation in titer and infectious-to-noninfectious particle ratios, which they controlled by using duplicate assays with separate viral preparations.

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

Integrity signals

Registry

Crossref · 10.1128/jvi.79.15.9933-9944.2005

Cites

59 of 60 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

20 of 49 cited sources checked · 7 supported · 1 flagged · accuracy not yet measured

  • Premisecitation
    § DISCUSSION

    Proteasomes in the cytoplasm act as barriers to AAV infection.

    “It was recently determined that AAV capsids are ubiquitinated, marking them for degradation by the proteasome (Fig.8IV) (50), adding more support to the notion that proteasomes in the cytoplasm act as barriers to AAV infection.”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [50] Yan, Z., R. Zak, G. W. Luxton, T. C. Ritchie, U. Bantel-Schaal, and J. F. Engelhardt. 2002. Ubiquitination of both adeno-associated virus type 2 and 5 capsid proteins affects the transduction efficiency of recombinant vectors. J. Virol. 76:2043-2053. [DOI] [PMC free article] [PubMed] [Google Scholar] source

      The Abstract reports that AAV-2 and AAV-5 capsids are ubiquitinated and that proteasome inhibitors increase transduction. The discussion (section labeled “4 μM Z-LLL”; page unavailable) says the consequence of ubiquitination is undefined and finds no evidence that the inhibitors improve transduction by preventing degradation of internalized virions. Thus the paper supports a proteasome-related barrier to transduction, but not the asserted degradation mechanism or its specific location in the cytoplasm. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
  • Premisecitation
    § DISCUSSION

    AAV capsids are ubiquitinated, marking them for degradation by the proteasome.

    “It was recently determined that AAV capsids are ubiquitinated, marking them for degradation by the proteasome (Fig.8IV) (50), adding more support to the notion that proteasomes in the cytoplasm act as barriers to AAV infection.”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [50] Yan, Z., R. Zak, G. W. Luxton, T. C. Ritchie, U. Bantel-Schaal, and J. F. Engelhardt. 2002. Ubiquitination of both adeno-associated virus type 2 and 5 capsid proteins affects the transduction efficiency of recombinant vectors. J. Virol. 76:2043-2053. [DOI] [PMC free article] [PubMed] [Google Scholar] source

      The Fig. 4 results (section labeled “4 μM Z-LLL”; page not provided) demonstrate ubiquitination of AAV-2 and AAV-5 capsid proteins in HeLa cells. The same section describes proteasomal degradation as a possibility, not an established consequence of that ubiquitination; it also reports no increase in viral-genome stability with proteasome inhibition. Thus the claim overstates the proposed degradation mechanism. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
  • Premisecitation
    § DISCUSSION

    Ordered DNA structure has been identified in crystal structures for canine parvovirus and MVM, illustrating that the genome is bound to the interior of the capsid by a specific nucleotide-capsid interaction.

    “It is important to note that ordered DNA structure has been identified in crystal structures for canine parvovirus (CPV) and MVM, illustrating that the genome is bound to the interior of the capsid by a specific nucleotide-capsid interaction (1, 7, 47, 49).”
    Quote in the paperSubstantial claim1 of 4 sources checked
    • cites [1] Agbandje-McKenna, M., A. L. Llamas-Saiz, F. Wang, P. Tattersall, and M. G. Rossmann. 1998. Functional implications of the structure of the murine parvovirus, minute virus of mice. Structure 6:1369-1381. [DOI] [PubMed] [Google Scholar] source
    • cites [7] Chapman, M. S., and M. G. Rossmann. 1995. Single-stranded DNA-protein interactions in canine parvovirus. Structure 3:151-162. [DOI] [PubMed] [Google Scholar]

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

    • cites [47] Wu, H., and M. G. Rossmann. 1993. The canine parvovirus empty capsid structure. J. Mol. Biol. 233:231-244. [DOI] [PubMed] [Google Scholar] source
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  • Premisecitation
    § RESULTS

    Proteasomes are a barrier for intracellular trafficking.

    “Proteasome inhibitors have been described in numerous studies to increase the transduction of rAAV postentry of the cell, suggesting that proteasomes are a barrier for intracellular trafficking (11, 51).”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites [11] Douar, A. M., K. Poulard, D. Stockholm, and O. Danos. 2001. Intracellular trafficking of adeno-associated virus vectors: routing to the late endosomal compartment and proteasome degradation. J. Virol. 75:1824-1833. [DOI] [PMC free article] [PubMed] [Google Scholar] source
    • cites [51] Yan, Z., R. Zak, Y. Zhang, W. Ding, S. Godwin, K. Munson, R. Peluso, and J. F. Engelhardt. 2004. Distinct classes of proteasome-modulating agents cooperatively augment recombinant adeno-associated virus type 2 and type 5-mediated transduction from the apical surfaces of human airway epithelia. J. Virol. 78:2863-2874. [DOI] [PMC free article] [PubMed] [Google Scholar] source
  • Premisecitation
    § RESULTS

    Proteasome inhibitors increase the transduction of recombinant AAV postentry of the cell.

    “Proteasome inhibitors have been described in numerous studies to increase the transduction of rAAV postentry of the cell, suggesting that proteasomes are a barrier for intracellular trafficking (11, 51).”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites [11] Douar, A. M., K. Poulard, D. Stockholm, and O. Danos. 2001. Intracellular trafficking of adeno-associated virus vectors: routing to the late endosomal compartment and proteasome degradation. J. Virol. 75:1824-1833. [DOI] [PMC free article] [PubMed] [Google Scholar] source
    • cites [51] Yan, Z., R. Zak, Y. Zhang, W. Ding, S. Godwin, K. Munson, R. Peluso, and J. F. Engelhardt. 2004. Distinct classes of proteasome-modulating agents cooperatively augment recombinant adeno-associated virus type 2 and type 5-mediated transduction from the apical surfaces of human airway epithelia. J. Virol. 78:2863-2874. [DOI] [PMC free article] [PubMed] [Google Scholar] source
  • Classified as probably not a substantial claim. 17
  • May combine two claims. 28

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

    Premisecitation
    § DISCUSSION

    Drugs/chemicals such as bafilomycin A, brefeldin A, and MG-132 augment rAAV transduction by acting on the level of endosome acidification, early-to-late endosome transition, and proteasome activity, respectively.

    “Studies have been carried out by a number of groups (11, 22, 50, 51) illustrating that drugs/chemicals such as bafilomycin A, brefeldin A, and MG-132 augment rAAV transduction by acting on the level of endosome acidification, early-to-late endosome transition, and proteasome activity, respectively.”
    Quote in the paperNot a substantial claim3 of 4 sources checked
    • cites [11] Douar, A. M., K. Poulard, D. Stockholm, and O. Danos. 2001. Intracellular trafficking of adeno-associated virus vectors: routing to the late endosomal compartment and proteasome degradation. J. Virol. 75:1824-1833. [DOI] [PMC free article] [PubMed] [Google Scholar] source
    • cites [22] Hansen, J., K. Qing, and A. Srivastava. 2001. Adeno-associated virus type 2-mediated gene transfer: altered endocytic processing enhances transduction efficiency in murine fibroblasts. J. Virol. 75:4080-4090. [DOI] [PMC free article] [PubMed] [Google Scholar] source

      The Results report that bafilomycin A inhibits endosomal acidification but significantly decreased AAV transduction in 293 cells and had little effect in NIH 3T3 cells—the opposite of the claimed augmentation. The supplied passages do not establish the claimed effects of brefeldin A or MG-132. (LLM, conf=0.89)

      Checked by a reasoning model — may be wrong.

      Experimental — accuracy not yet measured
    • cites [50] Yan, Z., R. Zak, G. W. Luxton, T. C. Ritchie, U. Bantel-Schaal, and J. F. Engelhardt. 2002. Ubiquitination of both adeno-associated virus type 2 and 5 capsid proteins affects the transduction efficiency of recombinant vectors. J. Virol. 76:2043-2053. [DOI] [PMC free article] [PubMed] [Google Scholar] source
    • cites [51] Yan, Z., R. Zak, Y. Zhang, W. Ding, S. Godwin, K. Munson, R. Peluso, and J. F. Engelhardt. 2004. Distinct classes of proteasome-modulating agents cooperatively augment recombinant adeno-associated virus type 2 and type 5-mediated transduction from the apical surfaces of human airway epithelia. J. Virol. 78:2863-2874. [DOI] [PMC free article] [PubMed] [Google Scholar] source

      The paper identifies MG132 (Z-LLL) as a proteasome inhibitor that can enhance rAAV transduction (introductory passage; Results). It does not address the claimed effects of bafilomycin A on endosome acidification or brefeldin A on early-to-late endosome transition. No page numbers are available in our copy. (LLM, conf=0.86)

      Experimental — accuracy not yet measured

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

    Premisecitation
    § DISCUSSION

    The early steps of AAV infection involve attachment to a variety of cell surface receptors such as HSPG, FGFR, αvβ5 integrin, and hepatocyte growth factor receptor (c-Met), followed by clathrin-dependent endocytosis.

    “The early steps of AAV infection involve attachment to a variety of cell surface receptors such as HSPG, FGFR, αvβ5 integrin, and hepatocyte growth factor receptor (c-Met) (Fig. 8I) (9, 25, 31, 39, 40), followed by clathrin-dependent endocytosis (Fig.8II).”
    Quote in the paperNot a substantial claim2 of 5 sources checked
    • cites [9] Di Pasquale, G., B. L. Davidson, C. S. Stein, I. Martins, D. Scudiero, A. Monks, and J. A. Chiorini. 2003. Identification of PDGFR as a receptor for AAV-5 transduction. Nat. Med. 9:1306-1312. [DOI] [PubMed] [Google Scholar] source

      The introduction lists HSPG, FGFR-1 and αvβ5 integrin among factors expressed by AAV-2-permissive cells, but does not identify c-Met as an AAV receptor. The Discussion also reports clathrin-coated-vesicle entry for AAV-5, rather than establishing that route for AAV generally. Page numbers are unavailable in our copy. (LLM, conf=0.86)

      Experimental — accuracy not yet measured
    • cites [25] Kashiwakura, Y., K. Tamayose, K. Iwabuchi, Y. Hirai, T. Shimada, K. Matsumoto, T. Nakamura, M. Watanabe, K. Oshimi, and H. Daida. 2005. Hepatocyte growth factor receptor is a coreceptor for adeno-associated virus type 2 infection. J. Virol. 79:609-614. [DOI] [PMC free article] [PubMed] [Google Scholar] source

      The opening summary identifies HSPG as the primary attachment receptor and FGFR1, αvβ5 integrin, and c-Met as AAV2 coreceptors. The Discussion also reports AAV2 internalization from clathrin-coated pits. However, the Results say c-Met did not increase AAV2 cell attachment, so describing c-Met as an attachment receptor is not supported. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
    • cites [31] Qing, K., C. Mah, J. Hansen, S. Zhou, V. Dwarki, and A. Srivastava. 1999. Human fibroblast growth factor receptor 1 is a co-receptor for infection by adeno-associated virus 2. Nat. Med. 5:71-77. [DOI] [PubMed] [Google Scholar] source
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      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites [40] Summerford, C., and R. J. Samulski. 1998. Membrane-associated heparan sulfate proteoglycan is a receptor for adeno-associated virus type 2 virions. J. Virol. 72:1438-1445. [DOI] [PMC free article] [PubMed] [Google Scholar]

      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).

    Premisecitation
    § Abstract

    In contrast to MVM and B19, the N termini of Vp1 and Vp2 of AAV are located within the virion.

    “In contrast, the N termini of Vp1 and Vp2 of AAV are located within the virion (27, 46, 48).”
    Quote in the paperNot a substantial claim2 of 3 sources checked
    • cites [27] Kronenberg, S., J. A. Kleinschmidt, and B. Bottcher. 2001. Electron cryo-microscopy and image reconstruction of adeno-associated virus type 2 empty capsids. EMBO Rep. 2:997-1002. [DOI] [PMC free article] [PubMed] [Google Scholar] source

      The Results (page not provided) conclude that VP1 and VP2 N-terminal extensions are likely inside AAV2 empty capsids, in contrast to evidence of outward extension in MVM and B19. The source presents the AAV2 location as an inference, not a directly determined fact, and does not establish it for AAV virions generally. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
    • cites [46] Wobus, C. E., B. Hugle-Dorr, A. Girod, G. Petersen, M. Hallek, and J. A. Kleinschmidt. 2000. Monoclonal antibodies against the adeno-associated virus type 2 (AAV-2) capsid: epitope mapping and identification of capsid domains involved in AAV-2-cell interaction and neutralization of AAV-2 infection. J. Virol. 74:9281-9293. [DOI] [PMC free article] [PubMed] [Google Scholar] source

      The Results map A1 and A69 epitopes to N-terminal regions of VP1 and VP2. The Discussion says these epitopes become partially masked during AAV-2 capsid assembly and describes some regions as probably buried; it does not establish that both N termini are located within the virion. Page numbers are unavailable in our copy. (LLM, conf=0.83)

      Experimental — accuracy not yet measured
    • cites [48] Xie, Q., W. Bu, S. Bhatia, J. Hare, T. Somasundaram, A. Azzi, and M. S. Chapman. 2002. The atomic structure of adeno-associated virus (AAV-2), a vector for human gene therapy. Proc. Natl. Acad. Sci. USA 99:10405-10410. [DOI] [PMC free article] [PubMed] [Google Scholar] source

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

    Premisecitation
    § Abstract

    Wild-type AAV virions are composed of three capsid proteins, Vp1, Vp2, and Vp3, produced in a 1:1:10 ratio from the same open reading frame by differential splicing and alternative translational start sites.

    “One primary difference is the fact that wild-type (wt) AAV utilizes three capsid subunits instead of two to form the virion shell.”
    • Also stated in: § Abstract · plain
      “The virion is composed of three capsid proteins, Vp1, Vp2, and Vp3, produced in a 1:1:10 ratio from the same open reading frame but from differential splicing (Vp1) and alternative translational start sites (Vp2 and Vp3, respectively) (30).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [30] Muralidhar, S., S. P. Becerra, and J. A. Rose. 1994. Site-directed mutagenesis of adeno-associated virus type 2 structural protein initiation codons: effects on regulation of synthesis and biological activity. J. Virol. 68:170-176. [DOI] [PMC free article] [PubMed] [Google Scholar] source

  • May combine two claims.

    Premisecitation
    § DISCUSSION

    Use of proteasome inhibitors such as MG-132 and LLnL increases transduction, providing evidence that after endosome escape, AAV must elude proteasomes in the cytoplasm while traversing to the nucleus.

    “Use of proteasome inhibitors such as MG-132 and LLnL have been shown to increase transduction, providing evidence that after endosome escape, AAV must elude proteasomes in the cytoplasm while traversing to the nucleus (Fig. 8IV and V) (11, 51).”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [11] Douar, A. M., K. Poulard, D. Stockholm, and O. Danos. 2001. Intracellular trafficking of adeno-associated virus vectors: routing to the late endosomal compartment and proteasome degradation. J. Virol. 75:1824-1833. [DOI] [PMC free article] [PubMed] [Google Scholar] source
    • cites [51] Yan, Z., R. Zak, Y. Zhang, W. Ding, S. Godwin, K. Munson, R. Peluso, and J. F. Engelhardt. 2004. Distinct classes of proteasome-modulating agents cooperatively augment recombinant adeno-associated virus type 2 and type 5-mediated transduction from the apical surfaces of human airway epithelia. J. Virol. 78:2863-2874. [DOI] [PMC free article] [PubMed] [Google Scholar] source

      The introductory passage identifies Z-LLL as MG132 and reports that it and LLnL enhance rAAV transduction; the Results also show that LLnL increases transduction and nuclear accumulation of viral DNA. But the Discussion says how these agents alter rAAV interactions with the proteasome remains unclear. The paper does not establish that, after escaping endosomes, AAV must elude cytoplasmic proteasomes on its way to the nucleus. (LLM, conf=0.88)

      Experimental — accuracy not yet measured

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

    Premisecitation
    § DISCUSSION

    Once AAV is in the cytoplasm en route to the nucleus, the virion is thought to be ubiquitinated, thereby being targeted for degradation by the proteasome.

    “Once AAV is in the cytoplasm en route to the nucleus, the virion is thought to be ubiquitinated (Fig. 8IV), thereby being targeted for degradation by the proteasome.”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [50] Yan, Z., R. Zak, G. W. Luxton, T. C. Ritchie, U. Bantel-Schaal, and J. F. Engelhardt. 2002. Ubiquitination of both adeno-associated virus type 2 and 5 capsid proteins affects the transduction efficiency of recombinant vectors. J. Virol. 76:2043-2053. [DOI] [PMC free article] [PubMed] [Google Scholar] source

      In the section labeled “4 μM Z-LLL” (page unavailable), the paper reports ubiquitination of AAV-2 and AAV-5 capsid proteins in infected HeLa cells. It treats proteasomal degradation of ubiquitinated virions as a possibility, not an established consequence: intact virions were poor substrates for ubiquitination in vitro, and proteasome inhibition did not increase intracellular viral DNA stability. The claimed sequence of an intact virion being ubiquitinated en route to the nucleus and thereby targeted for degradation is therefore not established by this source. (LLM, conf=0.87)

      Experimental — accuracy not yet measured

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

    Premisecitation
    § Abstract

    Vp1 is required for infectivity, while Vp2 has been shown to be nonessential.

    “While Vp1 is required for infectivity, Vp2 has been shown to be nonessential (44).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [44] Warrington, K. H., Jr., O. S. Gorbatyuk, J. K. Harrison, S. R. Opie, S. Zolotukhin, and N. Muzyczka. 2004. Adeno-associated virus type 2 VP2 capsid protein is nonessential and can tolerate large peptide insertions at its N terminus. J. Virol. 78:6595-6609. [DOI] [PMC free article] [PubMed] [Google Scholar] source

      The Discussion says VP2 is nonessential and VP1 is required for *efficient* viral infectivity. But it also reports that particles lacking VP1 have low infectivity, so the unqualified statement that VP1 is required for infectivity overstates the finding. (LLM, conf=0.88)

      Experimental — accuracy not yet measured

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

    Premisecitation
    § Abstract

    A phospholipase domain essential for viral infectivity has been identified in the unique N terminus of Vp1.

    “A phospholipase domain, essential for viral infectivity, has been identified in the unique N terminus of Vp1 (19, 53).”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [19] Girod, A., C. E. Wobus, Z. Zadori, M. Ried, K. Leike, P. Tijssen, J. A. Kleinschmidt, and M. Hallek. 2002. The VP1 capsid protein of adeno-associated virus type 2 is carrying a phospholipase A2 domain required for virus infectivity. J. Gen. Virol. 83:973-978. [DOI] [PubMed] [Google Scholar] source
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  • May combine two claims.

    Premisecitation
    § DISCUSSION

    Ordered DNA has yet to be discovered in the crystal structures solved for AAV, suggesting that DNA-capsid interactions may be lacking or not as important for AAV.

    “However, ordered DNA has yet to be discovered in the crystal structures solved for AAV, suggesting that DNA-capsid interactions may be lacking or not as important for AAV (42, 48).”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [42] Walters, R. W., M. Agbandje-McKenna, V. D. Bowman, T. O. Moninger, N. H. Olson, M. Seiler, J. A. Chiorini, T. S. Baker, and J. Zabner. 2004. Structure of adeno-associated virus serotype 5. J. Virol. 78:3361-3371. [DOI] [PMC free article] [PubMed] [Google Scholar] source

      The Methods (p. 2) say the AAV5 reconstruction used images of empty capsids, and the Results (p. 3) describe a cryo-EM reconstruction, not an AAV5 crystal structure. Searches for ordered DNA and DNA–capsid interactions found no passage stating whether ordered DNA appears in AAV crystal structures or drawing the claimed inference about the importance of those interactions. (LLM, conf=0.78)

      Experimental — accuracy not yet measured
    • cites [48] Xie, Q., W. Bu, S. Bhatia, J. Hare, T. Somasundaram, A. Azzi, and M. S. Chapman. 2002. The atomic structure of adeno-associated virus (AAV-2), a vector for human gene therapy. Proc. Natl. Acad. Sci. USA 99:10405-10410. [DOI] [PMC free article] [PubMed] [Google Scholar] source

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

    Premisecitation
    § Abstract

    Split vector systems exploiting head-to-tail concatamerization have been developed to circumvent the small packaging capacity of AAV genomes.

    “Recently, split vector systems, exploiting head-to-tail concatamerization formation, have been developed to circumvent the small packaging capacity of AAV genomes (13-16, 41, 52).”
    Quote in the paperNot a substantial claim1 of 6 sources checked
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  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation
    § DISCUSSION

    Data based on autonomous parvoviruses suggest that, prior to escaping the endosome, the virion undergoes conformational changes, leading to the exposure of the unique N terminus of Vp1, necessary for escape.

    “Data based on autonomous parvoviruses suggest that, prior to escaping the endosome, the virion is thought to undergo conformational changes, leading to the exposure of the unique N terminus of Vp1, necessary for escape (Fig. 8III) (5, 33).”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [5] Carreira, A., M. Menendez, J. Reguera, J. M. Almendral, and M. G. Mateu. 2004. In vitro disassembly of a parvovirus capsid and effect on capsid stability of heterologous peptide insertions in surface loops. J. Biol. Chem. 279:6517-6525. [DOI] [PubMed] [Google Scholar] source

      The introductory passage reports that heating minute virus of mice virions exposed the VP1 N terminus, and the Discussion describes a conformational rearrangement in VP2-only capsids. The paper does not establish that VP1 exposure occurs before endosomal escape or is necessary for that escape; its preliminary evidence concerns infectivity and possible uncoating in vivo. Page numbers are unavailable in our copy. (LLM, conf=0.85)

      Experimental — accuracy not yet measured
    • cites [33] Reguera, J., A. Carreira, L. Riolobos, J. M. Almendral, and M. G. Mateu. 2004. Role of interfacial amino acid residues in assembly, stability, and conformation of a spherical virus capsid. Proc. Natl. Acad. Sci. USA 101:2724-2729. [DOI] [PMC free article] [PubMed] [Google Scholar] source

  • May combine two claims.

    Findingown data
    § RESULTS

    Replicated monomer products can be detected for all virally delivered packaging constructs, but the replication dimer product for the L cassette is not detected at these exposure times.

    “Replicated monomer products can be detected for all of the virally delivered packaging constructs, but the replication dimer product for the L cassette is not detected at these exposure times.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Abstract

    Using reporter transgene cassettes ranging in size from 4.4 to 6.0 kb, AAV serotypes 1 through 5 with and without Vp2 could successfully package, replicate in, and transduce cells.

    “Using reporter transgene cassettes that range in size from 4.4 to 6.0 kb, we determined that serotypes 1 through 5 with and without Vp2 could successfully package, replicate in, and transduce cells.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data
    § RESULTS

    AAV is capable of encapsidating each CFTR cassette in its entirety and infecting target cells.

    “It is clear that AAV is capable of encapsidating each CFTR cassette in its entirety and infecting target cells (Fig. 7, left lanes 3, 4, and 5).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data
    § RESULTS

    The AAV2 E and K vectors were resistant to 37 and 45°C temperatures based on transduction but were negatively affected by a twofold decrease at 56°C.

    “The AAV2 E and K vectors were resistant to the 37 and 45°C temperatures based on transduction but were negatively affected (twofold decrease) by the 56°C temperature.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § DISCUSSION

    The inability of these viruses to infect cells efficiently was not due to their inability to bind and internalize into cells or to package incomplete genomes.

    “The inability of these viruses to infect cells efficiently was not due to their inability to bind and internalize into cells or package incomplete genomes (Fig. 3).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data
    § RESULTS

    Transduction is restored to wild-type levels for the K vector and to near wild-type levels for the L vector, with less than a twofold difference, in the presence of the proteasome inhibitor.

    “Upon comparison of the K and L AAV1 transduction profile in the presence of the proteasome inhibitor to that of the nontreated AAV1 E, it is clear that transduction is restored to wt levels for the K vector and to near wt levels for the L vector (less than twofold difference).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data
    § RESULTS

    DNA concentrations shown on alkaline agarose gels and quantitated by dot blots are similar between AAV2 D through L viruses but do not correlate with the infectivity of each virus.

    “DNA concentrations shown on the alkaline agarose gels and quantitated by dot blots are similar between the AAV2 D through L viruses but do not correlate with the infectivity of each virus.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data
    § Abstract

    Dot blot analysis established that packaging efficiency was similar for all vector cassettes and that the integrity of encapsidated genomes was intact regardless of size.

    “Dot blot analysis established that packaging efficiency was similar for all vector cassettes and that the integrity of encapsidated genomes was intact regardless of size.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data
    § RESULTS

    Dot blot analysis of 90 viruses showed that vector titers ranged from 10^6 to 10^8 viral genomes/μl for a majority of viral preparations, with little to no differences in titer between AAV produced with the largest cassettes (3 × 10^6 to 9 × 10^7 viral genomes/μl) and wild-type-size cassettes (6 × 10^6 to 1 × 10^8 viral genomes/μl).

    “Titers ranged from 106 to 108 viral genomes/μl for a majority of the viral preparations with little to no differences in titer between AAV produced with the largest cassettes (3 × 106 to 9 × 107 viral genomes/μl) compared to the wt size cassettes (6 × 106 to 1 × 108 viral genomes/μl).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data
    § RESULTS

    Virions lacking Vp2 do not encapsidate and transduce cells with the larger genomes more efficiently.

    “These data add more support to the previous claim that virions lacking Vp2 do not encapsidate and transduce cells with the larger genomes more efficiently.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationown data
    § DISCUSSION

    AAV encapsidating genomes larger than 5.2 kb are not influenced by the presence or absence of Vp2, distinguishing autonomous parvoviruses from AAV.

    “This study suggests that AAV encapsidating genomes larger than 5.2 kb are not influenced by the presence or absence of Vp2, distinguishing autonomous parvoviruses from AAV.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Premisecitation
    § Abstract

    Dong et al. generated packaging constructs containing a completely recombinant genome encoding the chloramphenicol acetyltransferase gene, ranging in size from 1,918 to 6,019 bp.

    “Dong et al. generated packaging constructs, containing a completely recombinant genome encoding the chloramphenicol acetyltransferase (CAT) gene, ranging in size from 1,918 to 6,019 bp (10).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [10] Dong, J. Y., P. D. Fan, and R. A. Frizzell. 1996. Quantitative analysis of the packaging capacity of recombinant adeno-associated virus. Hum. Gene Ther. 7:2101-2112. [DOI] [PubMed] [Google Scholar] source

  • May combine two claims.

    Interpretationown data
    § Abstract

    AAV is capable of packaging and protecting recombinant genomes as large as 6.0 kb, but the larger genome-containing virions are preferentially degraded by the proteasome, and this block can be overcome by the addition of proteasome inhibitors.

    “This study illustrates that AAV is capable of packaging and protecting recombinant genomes as large as 6.0 kb but the larger genome-containing virions are preferentially degraded by the proteasome and that this block can be overcome by the addition of proteasome inhibitors.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationown data
    § Abstract

    Vectors carrying larger genomes can be enhanced for more efficient transduction by the addition of proteasome inhibitors, suggesting a postentry block.

    “Vectors carrying larger genomes can be enhanced for more efficient transduction by the addition of proteasome inhibitors, suggesting a postentry block.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

    Premisenone given
    § Abstract

    Split vector systems require infection with numerous virus particles to increase the probability of transduction and are reliant on the efficiency of homologous recombination.

    “Cells have to be infected with numerous virus particles to increase the probability of transduction, and the system is reliant upon the efficiency of homologous recombination.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationown data
    § Abstract

    This study suggests that all AAV serotypes are capable of efficiently encapsidating genomes as large as 6 kb regardless of sequence, but the optimum packaging capacity is 5.23 kb.

    “This study suggests that all AAV serotypes are capable of efficiently encapsidating genomes as large as 6 kb regardless of sequence, but the optimum packaging capacity is 5.23 kb.”
    Quote in the paperSubstantial claim

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

    Premisecitation
    § DISCUSSION

    AAV requires endosomal acidification to escape from the late endosome and traffic to the nucleus.

    “Based on these studies, it has been proposed that AAV requires endosomal acidification to escape from the late endosome and traffic to the nucleus (Fig. 8III and IV).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation
    § Abstract

    Hermonat et al. inserted increments of 100 bp into the wild-type AAV genome downstream of the capsid gene, and viruses carrying larger genomes up to 5.6 kb were able to replicate and produce infectious virions, albeit at reduced efficiency compared to wild type.

    “Hermonat et al. inserted increments of 100 bp into the wt AAV genome downstream of the capsid gene (23). Viruses carrying larger genomes (up to 5.6 kb) were able to replicate and produce infectious virions, albeit at reduced efficiency compared to wt.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [23] Hermonat, P. L., J. G. Quirk, B. M. Bishop, and L. Han. 1997. The packaging capacity of adeno-associated virus (AAV) and the potential for wild-type-plus AAV gene therapy vectors. FEBS Lett. 407:78-84. [DOI] [PubMed] [Google Scholar] source

  • May combine two claims.

    Interpretationown data
    § Abstract

    A postentry step was responsible for the block in infection, and treatment of cells upon infection with proteasome inhibitors increased transduction of AAV encapsidating larger DNA templates to wild-type levels, suggesting preferential degradation of virions encapsidating larger-than-wild-type genomes.

    “Further analysis determined that a postentry step was responsible for the block in infection and specific treatment of cells upon infection with proteasome inhibitors increased transduction of AAV encapsidating larger DNA templates to wt levels, suggesting a preferential degradation of virions encapsidating larger-than-wt genomes.”
    Quote in the paperSubstantial claim

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

    Premisecitation
    § DISCUSSION

    Exposure of Vp1 may not be the only factor involved in escape from the endosome.

    “However, exposure of Vp1 may not be the only factor involved in escape from the endosome, as was indicated in a recent study with CPV (38).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [38] Suikkanen, S., M. Antila, A. Jaatinen, M. Vihinen-Ranta, and M. Vuento. 2003. Release of canine parvovirus from endocytic vesicles. Virology 316:267-280. [DOI] [PubMed] [Google Scholar] source

  • May combine two claims.

    Study design and conductnone given
    § RESULTS

    The dot blot method is effective to quantitate viral titers but is incapable of determining whether each AAV serotype has successfully packaged the larger transgene cassettes in their entirety.

    “The dot blot method is an effective method to quantitate viral titers, but it is incapable of determining whether each AAV serotype has successfully packaged the larger transgene cassettes in their entirety.”
    Quote in the paperSubstantial claim

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

    Premisecitation
    § DISCUSSION

    Genomes of identical size to wild type but possessing sequence foreign to wild type showed dissimilar packaging efficiencies, alluding to the importance of primary viral DNA sequence and possibly its structure on packaging into the capsid.

    “However, genomes of identical size to wt but possessing sequence foreign to wt showed dissimilar packaging efficiencies, alluding to the importance of primary viral DNA sequence and possibly its structure on packaging into the capsid.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [4] Brandenburger, A., E. Coessens, K. El Bakkouri, and T. Velu. 1999. Influence of sequence and size of DNA on packaging efficiency of parvovirus MVM-based vectors. Hum. Gene Ther. 10:1229-1238. [DOI] [PubMed] [Google Scholar] source

  • May combine two claims.

    Interpretationown data
    § DISCUSSION

    The restoration shifts the balance from proteasome degradation to nuclear accumulation, resulting in increased transduction.

    “Infectivity/transduction were restored to wt or near wt levels for AAV encapsidating the 5.3- and 6-kb genomes, respectively, shifting the balance from proteasome degradation to nuclear accumulation, resulting in increased transduction (Fig. 6).”
    Quote in the paperSubstantial claim

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

    Premisecitation
    § DISCUSSION

    Packaging capacity rarely exceeds 105 to 110% of the size of the wild-type genome.

    “The above studies have found that packaging capacity rarely exceeds 105 to 110% of the size of the wt genome.”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [2] Bett, A. J., L. Prevec, and F. L. Graham. 1993. Packaging capacity and stability of human adenovirus type 5 vectors. J. Virol. 67:5911-5921. [DOI] [PMC free article] [PubMed] [Google Scholar] source
    • cites [3] Bloss, T. A., and B. Sugden. 1994. Optimal lengths for DNAs encapsidated by Epstein-Barr virus. J. Virol. 68:8217-8222. [DOI] [PMC free article] [PubMed] [Google Scholar] source
    • cites [6] Chang, X. B., and J. H. Wilson. 1986. Formation of deletions after initiation of simian virus 40 replication: influence of packaging limit of the capsid. J. Virol. 58:393-401. [DOI] [PMC free article] [PubMed] [Google Scholar] source

  • May combine two claims.

    Premisecitation
    § Abstract

    Subsequent to infection, recombinant AAV can express a therapeutic gene and persist without integration into the host genome by existing episomally in circular head-to-tail concatemers.

    “Subsequent to infection, rAAV can express the therapeutic gene and persist without integration into the host genome by existing episomally in circular head-to-tail concatemers (29).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [29] McCarty, D. M., S. M. Young, Jr., and R. J. Samulski. 2004. Integration of adeno-associated virus (AAV) and recombinant AAV vectors. Annu. Rev. Genet. 38:819-845. [DOI] [PubMed] [Google Scholar] source

  • May combine two claims.

    Interpretationreasoning
    § Abstract

    The data gathered from these studies provide important information regarding AAV vector design and suggest that AAV packaging limits may not be restricted solely by the physical size of the vector template.

    “The data gathered from these studies provides important information regarding AAV vector design and suggests that AAV packaging limits may not be restricted solely by the physical size of the vector template.”
    Quote in the paperSubstantial claim

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

    Study design and conductown data
    § RESULTS

    Transduction assays were carried out in duplicate with separate viral preparations, and the transduction profiles depicted in Fig. 5 top and middle panels were found to hold true for each AAV serotype with and without Vp2.

    “To control for these inconsistencies, transduction assays were carried out in duplicate with separate viral preparations, and the transduction profiles depicted in Fig. 5 (top and middle panels) were found to hold true for each AAV serotype with and without Vp2.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Premisenone given
    § Abstract

    The two split-vector approaches, trans-splicing and homologous recombination, depend upon recombination between two vector genomes, each encoding approximately half the transgene, within the same cell to achieve gene expression.

    “The two approaches, trans-splicing and homologous recombination methods, depend upon recombination between two vector genomes (each genome encoding approximately half the transgene) within the same cell to achieve gene expression.”
    Quote in the paperSubstantial claim
39 of 39

  • The paper relies on this without support.

    AAV's limited packaging capacity impedes gene therapy for diseases associated with larger genes.

    “The limited packaging capacity of adeno-associated virus (AAV) precludes the design of vectors for the treatment of diseases associated with larger genes.”
    “limited packaging capacity has been an impediment for AAV-mediated gene therapy of Duchenne muscular dystrophy, hemophilia A, cystic fibrosis, and other genetic diseases where the length of the coding sequence is equal in size to the wt AAV genome.”

  • The paper relies on this without support.

    Autonomous parvoviruses MVM and B19 package larger genomes of 5.1 and 5.6 kb, respectively, compared to AAV genomes of 4.7 kb.

    “Autonomous parvoviruses, such as minute virus of mice and B19, while identical in size (25 nm), are known to package larger genomes of 5.1 and 5.6 kb, respectively, compared to AAV genomes of 4.7 kb.”
    “Other parvoviruses have been shown to package genomes as large as 5.1 and 5.6 kb (minute virus of mice [MVM] and B19, respectively).”

  • The paper relies on this without support.

    The functional significance of Vp2 remains unresolved.

    “The functional significance of Vp2 remains to be resolved.”

  • The paper relies on this without support.

    MVM and B19 are initially composed of two structural proteins, Vp1 and Vp2, and the N termini of the minor capsid components are exposed on the surface of the virion subsequent to genome encapsidation.

    “A striking structural difference is that MVM and B19 are initially composed of two structural proteins (Vp1 and Vp2), and the N termini of the minor capsid components (Vp1 and Vp2 for B19 and Vp2 for MVM) are exposed on the surface of the virion subsequent to genome encapsidation.”

  • The paper relies on this without support.

    Recombinant AAV utilizes cis-acting 145-bp inverted terminal repeats to flank vector transgene cassettes, providing up to 4.5 kb for packaging of foreign DNA.

    “Similar to wt AAV, recombinant AAV (rAAV) utilizes the cis-acting 145-bp ITRs to flank vector transgene cassettes, providing up to 4.5 kb for packaging of foreign DNA.”

  • The paper relies on this without support.

    AAV's small size is a major limitation for its use in therapies for diseases associated with larger genes, such as cystic fibrosis.

    “However, its small size has been identified as a major limitation for its use in therapies for diseases associated with larger genes, such as cystic fibrosis.”

  • The paper relies on this without support.

    AAV is not dependent on nucleotide-capsid interactions because its genome produces the Vp3 subunit from an independent start codon.

    “AAV is not dependent on this mechanism because its genome produces the Vp3 subunit from an independent start codon.”
7 of 7

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 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.”

    From AAVrh.10-Mediated APOE2 Central Nervous System Gene Therapy for APOE4-Associated Alzheimer's Disease (2018) · cites this paper as [67]

    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.

    Experimental — accuracy not yet measured

  • Vector reconstitution has been reported in vitro in several cell lines, and in vivo in mouse liver, skeletal muscle, and retina.

    “Vector reconstitution has been reported in vitro in several cell lines, and in vivo in mouse liver, skeletal muscle, and retina (Grieger and Samulski, 2005).”

    From Evaluating Efficiencies of Dual AAV Approaches for Retinal Targeting (2017) · cites this paper as Grieger and Samulski, 2005

    The introductory passage labelled Abstract describes split-vector systems that rely on recombination of two vector genomes within a cell, supporting the general idea of vector reconstitution. It does not report reconstitution in several cell lines or in mouse liver, skeletal muscle, or retina. The Results describe transduction of cultured cells, not those specific reconstitution findings; page numbers are unavailable in our copy. (LLM, conf=0.78)

    Experimental — accuracy not yet measured

  • Vectors carrying larger genomes have lower transduction capacity, most likely due to preferential degradation of vectors encapsidating larger genomes.

    “It has also been shown that vectors carrying larger genomes have lower transduction capacity, most likely due to a preferential degradation of vectors encapsidating larger genomes (Grieger and Samulski, 2005).”

    From Evaluating Efficiencies of Dual AAV Approaches for Retinal Targeting (2017) · cites this paper as Grieger and Samulski, 2005

Cites

Flagged first, then by citations

Research works printed but not linked: 1

  1. Sambrook J. and D. W. Russell. 2001. Molecular cloning: a laboratory manual 3rd ed. Cold Spring Harbor Laboratory Press Cold Spring Harbor N.Y.

Cited by

Sorted by citations

Related

Authors
Grieger, J. C., & Samulski, R. J.
Affiliations
University of North Carolina at Chapel Hill (US)
Corresponding author
Samulski, Richard J.
ORCID
Samulski, Richard J.
Venue
Journal of Virology
Publisher
American Society for Microbiology
Published
2005-08
Volume
79
Issue
15
Pages
9933-9944
ISSN
  • 0022-538X (ISSN-L)
  • 1098-5514
DOI
10.1128/jvi.79.15.9933-9944.2005
PMC
PMC1181570
OpenAlex
W1995793532
Cited by
419
References
57
Citations by year
2026: 22 · 2025: 33 · 2024: 29 · 2023: 24 · 2022: 42 · 2021: 24 · 2020: 31 · 2019: 29 · 2018: 19 · 2017: 22 · 2016: 8 · 2015: 20 · 2014: 11 · 2013: 13 · 2012: 19
FWCI
5.18
Type
journal article
Language
en
Open access
Licence
journals.asm.org/non-commercial-tdm-license (tdm)
Locations
  • Journal of Virology (publishedVersion)
  • Europe PMC (PubMed Central) (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
  • Carolina Digital Repository (University of North Carolina at Chapel Hill) (submittedVersion)
  • UNC Libraries
Funders
  • National Institutes of Health (5p01gm059299-10, DK065988)
  • National Heart, Lung, and Blood Institute (P01 HL-051818, 5P01HL066973, P01 HL066973, 2P01 HL 051818)
  • National Institute of General Medical Sciences (P01 GM-059299, 5P01GM05988)
  • National Institute of Diabetes and Digestive and Kidney Diseases (P30DK065988)
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Virus-based gene therapy research
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › RNA Interference and Gene Delivery
  • Health Sciences › Medicine › Infectious Diseases › Parvovirus B19 Infection Studies
Keywords
adeno-associated virus, AAV serotypes, packaging capacity, genome size, transduction efficiency, proteasomal degradation, CFTR gene therapy, adeno-associated virus vectors, minute virus of mice, viral capsid
MeSH terms
Dependovirus, Animals, Chlorocebus aethiops, Genetic Vectors, Humans, Gene Expression, Genome, Viral, Gene Deletion, Cystic Fibrosis Transmembrane Conductance Regulator, Virus Assembly, COS Cells, Capsid Proteins

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 2026-10-28.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-28.

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.

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