Multi-omics analyses reveal novel effects of PLCγ2 deficiency in the mouse brain

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

Other more strongly hypermorphic PLCG2 variants are associated with APLAID, while other loss-of-function PLCG2 variants are associated with CVID and PLAID.

“Other more strongly hypermorphic PLCG2 variants are associated with autoimmune PLCγ2-associated antibody deficiency and immune dysregulation (APLAID) (15), while other loss-of-function PLCG2 variants are associated with common variable immunodeficiency (CVID) and PLAID (18).”

• cites [15] H. Jing , et al., Phospholipase Cγ2 regulates endocannabinoid and eicosanoid networks in innate immune cells. Proc. Natl. Acad. Sci. U. S. A. 118 (2021). sourcePartly supported

  The source’s Abstract (page unavailable) links germline PLCG2 exon deletions to PLAID, supporting that disease association. It does not identify those variants as loss-of-function or link PLCG2 variants to CVID. The APLAID clause carries a different citation, so it is not the basis of this verdict. (LLM, conf=0.86)

  Experimental — accuracy not yet measured
• cites [18] J. T. Jackson , E. Mulazzani , S. L. Nutt , S. L. Masters , The role of PLCγ2 in immunological disorders, cancer, and neurodegeneration. J. Biol. Chem. 297 (2021). sourcePartly supported

  The “PLCγ2 and immune deficiency” section (page unavailable) links PLCG2 mutations to both CVID and PLAID, but does not identify the CVID mutations as loss-of-function. It explicitly describes PLAID as driven by a gain-of-function mutation, contrary to the loss-of-function description. The separate APLAID clause is attached to citation (15), not this source’s citation (18). (LLM, conf=0.88)

  Experimental — accuracy not yet measured

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

TREM2 and CD33 are also Alzheimer's disease risk genes.

“In the brain, PLCγ2 is primarily expressed by microglia, where it serves as an important signaling node downstream of TREM2 and CD33 (19, 20), both also AD risk genes (21–23).”

• cites [21] sourceSupported
• cites [22] sourceSupported
• cites [23] sourceNot checked — no full text of the source

May combine two claims.

In the brain, PLCγ2 is primarily expressed by microglia, where it serves as an important signaling node downstream of TREM2 and CD33.

“In the brain, PLCγ2 is primarily expressed by microglia, where it serves as an important signaling node downstream of TREM2 and CD33 (19, 20), both also AD risk genes (21–23).”

• cites [19] sourceNot checked — no full text of the source
• cites [20] sourcePartly supported

  The section on other AD risk genes says PLCG2 is preferentially or selectively expressed in microglia, and the gene table places it downstream of SYK during ITAM signaling, consistent with a role in TREM2 signaling. It does not place PLCG2 downstream of CD33; the same section describes CD33 as an inhibitory receptor that opposes ITAM receptors and SYK. (LLM, conf=0.88)

  Experimental — accuracy not yet measured

May combine two claims.

PLCG2 polymorphisms are associated with both reduced and increased risk of Alzheimer's disease and with longevity.

“PLCG2 polymorphisms are associated with both reduced and increased risk of Alzheimer’s disease (AD) and with longevity.”

• Also stated in: § Introduction · plain

  “Multiple PLCG2 gene polymorphisms have been recently associated with Alzheimer’s disease (AD), including rare coding variants that increase (e.g. M28L, rs61749044) and reduce (e.g. P522R, rs72824905) risk of Alzheimer’s disease (AD) and increase the likelihood of longevity (P522R) (1–10).”

• cites [1] sourceCould not verify

  The Results and Discussion passages concern PLX3397 treatment, amyloid accumulation, and oligomers in 5XFAD mice; they do not address PLCG2 polymorphisms or longevity. Searches for PLCG2 variants and for genetic associations with Alzheimer’s risk and longevity found no passage supporting the claim. Page numbers were not available in our copy. (LLM, conf=0.78)

  Experimental — accuracy not yet measured
• cites [2] sourcePartly supported

  The Conclusions (page unavailable) state that the PLCG2 rs72824905-G allele is associated with decreased Alzheimer’s disease risk and an increased chance of longevity. The paper does not establish the claim’s additional association between PLCG2 polymorphisms and increased Alzheimer’s disease risk. (LLM, conf=0.90)

  Experimental — accuracy not yet measured
• cites [3] 2017, Rare coding variants in PLCG2, ABI3, and TREM2 implicate microglial-mediated innate immunity in Alzheimer’s disease.Not matched

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

• cites [4] 2020, PLCG2 protective variant p.P522R modulates tau pathology and disease progression in patients with mild cognitive impairment, Acta Neuropathol. sourcePartly supported

  The Introduction (page not available) says the PLCG2 p.P522R variant protects against Alzheimer’s disease and reports a suggested positive effect on longevity. Neither that passage nor the retrieved passages identify a PLCG2 variant associated with increased Alzheimer’s risk, so that part of the claim is unsupported by our copy. (LLM, conf=0.88)

  Experimental — accuracy not yet measured
• cites [5] sourceCould not verify

  The ACE2 and APOE4 sections discuss genetic variants and Alzheimer’s disease risk, but neither addresses PLCG2 or longevity. Searches for PLCG2 polymorphisms and phospholipase C gamma 2 variants found no passage in our copy supporting the attributed associations; no page numbers were provided. (LLM, conf=0.76)

  Experimental — accuracy not yet measured
• cites [6] R. E. Marioni , et al., GWAS on family history of Alzheimer’s disease. Transl. Psychiatry 8 (2018). sourcePartly supported

  The Results section (‘Novel genome-wide significant loci’; page unavailable) identifies a PLCG2 SNP, rs12444183, at a genome-wide significant Alzheimer’s disease risk locus. It does not establish that PLCG2 polymorphisms are associated with both reduced and increased AD risk. The paper’s references to longevity in the Methods and Discussion concern parental age and case ascertainment, not an association between PLCG2 and longevity. (LLM, conf=0.88)

  Experimental — accuracy not yet measured
• cites [7] sourceCould not verify

  The Results sections on PNN degradation and hippocampal place coding (page unavailable) concern grid-cell activity in rats, not human genetic associations. Searches for PLCG2 polymorphisms, Alzheimer’s disease risk, and longevity found no passage addressing the claim in our copy. (LLM, conf=0.76)

  Experimental — accuracy not yet measured
• cites [8] A. P. Tsai , et al., PLCG2 as a Risk Factor for Alzheimer’s Disease. bioRxiv, 2020.05.19.104216 (2020). sourcePartly supported

  The Discussion reports that different PLCG2 variants may increase or reduce late-onset Alzheimer’s disease risk, and the Abstract identifies M28L as an increased-risk variant. Longevity appears only in the title of another study listed in the References; this paper does not itself report or discuss a longevity association. (LLM, conf=0.87)

  Experimental — accuracy not yet measured
• cites [9] sourceSupported
• cites [10] 2020, Examination of the Effect of Rare Variants in TREM2, ABI3, and PLCG2 in LOAD Through Multiple Phenotypes, J. Alzheimers. Dis sourcePartly supported

  The Results (page unavailable) report that PLCG2 p.P522R was associated with reduced Alzheimer’s disease risk, and the Discussion (page unavailable) links it to enrichment in healthy centenarians. The Results attribute increased Alzheimer’s risk to variants in TREM2 and ABI3, not PLCG2; the cited paper does not support the claim that PLCG2 polymorphisms are associated with increased risk. (LLM, conf=0.88)

  Experimental — accuracy not yet measured

May combine two claims.

Expression of PLCγ2 M28L in the mouse brain led to a transcriptomic profile that correlated with human AD modules and led to increased microglia density when fed a high fat diet.

“Expression of PLCγ2 M28L in the mouse brain led to a transcriptomic profile that correlated with human AD modules and led to increased microglia density when fed with a high fat diet (17).”

• cites [17] A. L. Oblak , et al., Plcg2M28L Interacts With High Fat/High Sugar Diet to Accelerate Alzheimer’s Disease-Relevant Phenotypes in Mice. Front. Aging Neurosci. 14 (2022). sourcePartly supported

  The Results section reports that Plcg2M28L and its interaction with a high-fat diet correlated with human AD gene-expression modules. It also reports increased microglial density in high-fat-fed female LOAD1.Plcg2M28L mice, but the claim omits the sex restriction and implies a general increase across the mouse brain. The Results specify the cortex, while the Discussion describes the increase as limited to the hippocampus; our copy does not resolve that discrepancy. No page numbers are provided. (LLM, conf=0.85)

  Experimental — accuracy not yet measured

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

PLCG2 expression is associated with both amyloid and tau pathology.

“PLCG2 expression has also been associated with both amyloid and tau pathology (4, 11).”

• cites [4] 2020, PLCG2 protective variant p.P522R modulates tau pathology and disease progression in patients with mild cognitive impairment, Acta Neuropathol. sourcePartly supported

  The Discussion (page unavailable) links the PLCG2 p.P522R variant to reduced tau pathology in patients with mild cognitive impairment, with its strongest effect when amyloid pathology is present. That supports a connection to both pathologies, but the paper does not establish that PLCG2 expression itself is associated with both; it studies variant status and a separate co-expression network. (LLM, conf=0.86)

  Experimental — accuracy not yet measured
• cites [11] A. P. Tsai , et al., PLCG2 is associated with the inflammatory response and is induced by amyloid plaques in Alzheimer’s disease. Genome Med. 14 (2022). sourcePartly supported

  The Results section ('Increased PLCG2 expression levels are associated with amyloid plaques in the human brain'; page not provided) reports an association between PLCG2 expression and amyloid plaque density in three brain regions. It does not establish an association with tau pathology; the Discussion (page not provided) instead reports no increase in Plcg2 expression in a tauopathy mouse model. (LLM, conf=0.90)

  Experimental — accuracy not yet measured

May combine two claims.

In microglia, PLCγ2 activity is downstream of TREM2 and Fc receptors, regulating inflammatory processes, migration, and endocytosis.

“In microglia PLCγ2 activity has been documented to be downstream of TREM2 (19) and Fc receptors (15), regulating inflammatory processes, migration, and endocytosis (13, 16, 25, 33, 34).”

• cites [19] sourceNot checked — no full text of the source
• cites [15] H. Jing , et al., Phospholipase Cγ2 regulates endocannabinoid and eicosanoid networks in innate immune cells. Proc. Natl. Acad. Sci. U. S. A. 118 (2021). sourcePartly supported

  The Results report that PLCγ2 loss impairs prostaglandin production and microglial activation in response to inflammatory stimuli, with a possible effect on phagocytosis. The Discussion also describes PLCγ2 as signaling downstream of TREM2 in microglia. Our copy does not establish a role in microglial migration or endocytosis; its endocytosis mention is in the title of a referenced study. (LLM, conf=0.86)

  Experimental — accuracy not yet measured
• cites [13] 13. E. Maguire,, 2021, PIP2 depletion and altered endocytosis caused by expression of Alzheimer’s disease-protective variant PLCγ2 R522 sourceSupported
• cites [16] sourceSupported
• cites [25] J. Obst , et al., PLCγ2 regulates TREM2 signalling and integrin-mediated adhesion and migration of human iPSC-derived macrophages. Sci. Rep. 11 (2021). sourceSupported
• cites [33] 2023, Carriers of the p.P522R variant in PLCγ2 have a slightly more responsive immune system, Mol. Neurodegener.Not matched

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

• cites [34] S. Solomon , et al., Heterozygous expression of the Alzheimer’s disease-protective PLCγ2 P522R variant enhances Aβ clearance while preserving synapses. Cell. Mol. Life Sci. 79 (2022). sourceSupported

May combine two claims.

A previous study examining microglia gene expression from Plcg2 KO mice also found rewiring of PIP2 and DAG metabolism, with decreases in DGKE and DAGL which both degrade DAG and increases in PLA2G4A which shunts PI away from production of PIP2 to generate free fatty acids such as arachidonic acid.

“A previous study examining microglia gene expression from Plcg2 KO mice also found rewiring of PIP2 and DAG metabolism, with decreases in DGKE and DAGL which both degrade DAG and increases in PLA2G4A which shunts PI away from production of PIP2 to generate free fatty acids such as arachidonic acid (15).”

• cites [15] H. Jing , et al., Phospholipase Cγ2 regulates endocannabinoid and eicosanoid networks in innate immune cells. Proc. Natl. Acad. Sci. U. S. A. 118 (2021). sourcePartly supported

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

  Experimental — accuracy not yet measured

May combine two claims.

Our results are consistent with the 'buffering' of global plasma membrane PIP2 pool hypothesis, which proposes that stimulation of PIP2 hydrolysis occurs concurrently with an activation of PIP2 synthesis via Ca2+-sensitive stimulation of PI4-kinase.

“Our results are consistent with the ‘buffering’ of global plasma membrane PIP2 pool hypothesis(31), which proposes that stimulation of PIP2 hydrolysis (e.g. via PLCγ2) occurs concurrently with an activation of PIP2 synthesis via Ca2+-sensitive stimulation of PI4-kinase(32).”

• cites [31] sourceSupported
• cites [32] sourceSupported

• AssumptionRests on an assumption: PLCγ2 catalyzes the hydrolysis of PIP2 to DAG and IP3.

May combine two claims.

Three under-expressed pathways were related to aging, consistent with the previously reported association between PLCG2 and longevity.

“On the other hand, three under-expressed pathways were related to aging, consistent with the previously reported association between PLCG2 and longevity(2).”

• cites [2] sourceSupported

Classified as probably not a substantial claim.

Differential gene expression analysis was performed using DESeq2, controlling for sex and W1.

“Differential gene expression analysis was performed using the DESeq2 R package (52), controlling for sex and W1.”

• cites [52] M. I. Love , W. Huber , S. Anders , Moderated estimation of fold change and dispersion for RNA-seq data with DESeq2. Genome Biol. 15 (2014). sourceSupported

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

The overall decreases in myelin lipids in Plcg2 KO mice may be due to cell autonomous effects of PLCG2 loss.

“suggesting that perhaps the overall decreases in myelin lipids in Plcg2 KO mice may be due to cell autonomous effects of PLCG2 loss.”

• cites [36] S. Morabito , et al., Single-nucleus chromatin accessibility and transcriptomic characterization of Alzheimer’s disease. Nat. Genet. 53 (2021). sourceCould not verify

  The Results section on oligodendrocyte co-expression reports reduced expression of a myelination-related gene module in Alzheimer’s disease, and the Discussion describes altered lipid-regulatory signaling in human oligodendrocytes. Neither addresses myelin lipid levels in Plcg2 knockout mice or whether PLCG2 loss has cell-autonomous effects (searched: PLCG2, knockout mice, myelin lipids). (LLM, conf=0.76)

  Experimental — accuracy not yet measured
• cites [37] L. Brase , et al., A landscape of the genetic and cellular heterogeneity in Alzheimer disease. medRxiv 4 (2022). sourceNot checked — no full text of the source
• cites [38] S. Jäkel , et al., Altered human oligodendrocyte heterogeneity in multiple sclerosis. Nature 566 (2019). sourceCould not verify

  The cited paper discusses oligodendrocyte populations and myelin-gene expression in human multiple sclerosis tissue (Abstract; no page supplied). Searches for PLCG2, Plcg2 knockout mice, myelin lipids, and cell-autonomous effects found no passage addressing the proposed explanation for lipid decreases. (LLM, conf=0.76)

  Experimental — accuracy not yet measured

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

PLCγ2 is an important downstream mediator of B cell and T cell receptors.

“PLCγ2 is an important downstream mediator of B cell an T cell receptors (18).”

• cites [18] J. T. Jackson , E. Mulazzani , S. L. Nutt , S. L. Masters , The role of PLCγ2 in immunological disorders, cancer, and neurodegeneration. J. Biol. Chem. 297 (2021). sourceSupported

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

PLCγ2 is necessary for separation of blood and lymphatic vessels in mice and osteoclastogenesis, and PLCγ2 outside of the brain has roles in immune deficiencies, autoimmunity, and cancer.

“PLCγ2 is necessary for separation of blood and lymphatic vessels in mice (29) and osteoclastogenesis (42), and PLCγ2 outside of the brain has roles in immune deficiencies, autoimmunity, and cancer (18).”

• cites [29] sourceNot checked — no full text of the source
• cites [42] sourceSupported
• cites [18] J. T. Jackson , E. Mulazzani , S. L. Nutt , S. L. Masters , The role of PLCγ2 in immunological disorders, cancer, and neurodegeneration. J. Biol. Chem. 297 (2021). sourceSupported

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

Quality control was performed using RUV_total to generate W1 for correcting unwanted sources of sample-level variance.

“Quality control was performed using the RUV_total function from the NanoNormIter R package to generate a continuous metadata value (“W1”) for each sample, which was used for correcting unwanted sources of sample-level variance (51).”

• cites [51] A. Bhattacharya , et al., An approach for normalization and quality control for NanoString RNA expression data. Brief. Bioinform. 22 (2021). sourcePartly supported

  The Normalization section says the paper estimated unwanted technical factors using RUVg from RUVSeq and removed estimated variation using limma’s removeBatchEffects. This supports the general purpose of correcting unwanted variation, but not the attributed use of RUV_total from NanoNormIter or generation of a per-sample value called W1. Page numbers were not available in our copy. (LLM, conf=0.88)

  Experimental — accuracy not yet measured

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

Loss of PLCγ2 enhances T cell mediated oligodendrocyte and microglia dyshomeostasis, which could explain the results showing that myelin lipids decrease in PLCγ2 KO mice.

“perhaps loss of PLCγ2 enhances T cell mediated oligodendrocyte and microglia dyshomeostasis which could explain our results showing that myelin lipids decrease in PLCγ2 KO mice (Figure 3A–C).”

• cites [43] 2022, CD8+ T cells induce interferon-responsive oligodendrocytes and microglia in white matter aging, Nat. Neurosci sourcePartly supported

  The Results section reports that CD8+ T cells induce interferon-responsive oligodendrocytes and microglia in aged white matter, and that mice lacking functional CD8+ T cells have less oligodendrocyte loss. It does not establish that loss of PLCγ2 enhances those T-cell-mediated changes. The decrease in myelin lipids is described in the citing sentence as the citing authors’ own result, not a finding attributed to this source. Page numbers were not available in our copy. (LLM, conf=0.87)

  Experimental — accuracy not yet measured

May combine two claims.

Microglia-oligodendrocyte interactions may account for the change in myelin lipids in Plcg2 KO mice, since microglia are critical for the development of myelin and Plcg2 is disrupted constitutively.

“Microglia-oligodendrocyte interactions may account for this change in myelin lipids since microglia are critical for the development of myelin (35) and in the study herein Plcg2 is disrupted constitutively.”

• Also stated in: § Discussion · hedged

  “PLCγ2 mRNA has relatively low expression in oligodendrocytes compared to microglia (12), so it is likely that microglia-oligodendrocyte interactions may account for this change in myelin lipids since microglia are critical for the development of myelin (35).”

• cites [35] A. Wlodarczyk , et al., A novel microglial subset plays a key role in myelinogenesis in developing brain. EMBO J. 36 (2017). sourceSupported

May combine two claims.

Microglia are the main cell type that express Plcg2 in the brain, with relatively low expression in oligodendrocytes, the cells that produce myelin.

“These results were surprising given that microglia are the main cell type that express Plcg2 in the brain, with relatively low expression in oligodendrocytes, the cells that produce myelin (12).”

• cites [12] L. Magno , et al., Alzheimer’s disease phospholipase C-gamma-2 (PLCG2) protective variant is a functional hypermorph. Alzheimer’s Res. Ther. 11, 16 (2019). sourceSupported

May combine two claims.

Previously published transcriptome data from neonatal microglia isolated from Plcg2 KO mice found reduced expression of disease-associated microglia markers, reduced expression of genes associated with lysosomal function, phagocytosis of apoptotic cells, and extracellular matrix degradation, and increased expression of complement, major histocompatibility complex, inflammatory chemokine, and Inter

“which found reduced expression of disease-associated microglia markers, as well as reduced expression of genes associated with lysosomal function, phagocytosis of apoptotic cells, and extracellular matrix degradation and increased expression of complement, major histocompatibility complex, inflammatory chemokine, and interferon response genes (15).”

• cites [15] H. Jing , et al., Phospholipase Cγ2 regulates endocannabinoid and eicosanoid networks in innate immune cells. Proc. Natl. Acad. Sci. U. S. A. 118 (2021). sourceSupported

May combine two claims.

PLCγ2 depletion led to significant losses of myelin-specific lipids and decreasing trends of myelin-enriched lipids.

“In addition, PLCγ2 depletion led to significant losses of myelin-specific lipids and decreasing trends of myelin-enriched lipids.”

May combine two claims.

Exploratory proteomic pathway analyses revealed changes in KO and HET females compared to WTs, with over-abundant proteins pointing to mTOR signaling, and under-abundant proteins to oligodendrocytes.

“Exploratory proteomic pathway analyses revealed changes in KO and HET females compared to WTs, with over-abundant proteins pointing to mTOR signaling, and under-abundant proteins to oligodendrocytes.”

May combine two claims.

There was a significant main effect of genotype, with a specific loss of PIP2 in Plcg2 KO males compared to sex-matched WT and HET mice and a decreasing trend in females.

“We also found no changes in total PIP or PIP3 levels in the cerebrum (Figure 4E and 4G), but we did observe a significant main effect of genotype, with a specific loss of PIP2 in Plcg2 KO males compared to sex-matched WT and HET mice and a decreasing trend in females (Figure 4F).”

May combine two claims.

There were decreasing trends in markers of neurodegenerative microglia (MgND, p=0.081) and stage 1 disease associated microglia (DAM) markers (p=0.178).

“Similarly, we found decreasing trends in markers of neurodegenerative microglia (MgND, p=0.081, Supplemental Figure 3B) and stage 1 disease associated microglia (DAM) markers (p=0.178, Supplemental Figure 3C).”

May combine two claims.

DESeq2 likelihood ratio test differential gene expression analysis revealed six female differentially expressed genes but not a single male differentially expressed gene.

“Furthermore, DESeq2 likelihood ratio test (LRT) differential gene expression analysis revealed six female DEGs (Figure 5I, Supplemental Dataset 6) but not a single male DEG (Supplemental Figure 2I).”

May combine two claims.

There was a significant decrease of cerebrosides in the cerebrum that was dependent on genotype and sex, with significantly less total cerebroside in Plcg2 KO mice compared to both WT and HET mice of both sexes.

“We found a significant decrease of cerebrosides in the cerebrum that was dependent on genotype and sex, with post-hoc analysis revealing significantly less total cerebroside in Plcg2 KO mice compared to both WT and HET mice of both sexes (Figure 3A).”

May combine two claims.

Although we found expected decreases in one of the products of the PLCγ2 enzymatic reaction, i.e. DAG, in Plcg2 KO mice, we found a decrease in the substrate of PLCγ2 enzymatic reaction, i.e. PIP2, rather than the expected accumulation.

“Although we found expected decreases in one of the products of the PLCγ2 enzymatic reaction, i.e. DAG, in Plcg2 KO mice (Figure 3), we found a decrease in the substrate of PLCγ2 enzymatic reaction, i.e. PIP2 (Figure 3), rather than the expected accumulation.”

• AssumptionRests on an assumption: PLCγ2 catalyzes the hydrolysis of PIP2 to DAG and IP3.

May combine two claims.

One out of two Plcg2 KO males survived until weaning age, while only one out of five Plcg2 KO females did so.

“In other words, one out of two Plcg2 KO males survived until weaning age, while only one out of five Plcg2 KO females did so.”

May combine two claims.

Further examination of N- and OH-sulfatide revealed a trending decrease in PLCG2 KO compared to WT mice (p=0.13) and a main effect of sex.

“There were no significant changes in total cerebrum sulfatide (Figure 3D), but further examination of N- and OH-sulfatide revealed a trending decrease in PLCG2 KO compared to WT mice (p=0.13, Figure 3E) and a main effect of sex (Figure 3F), respectively.”

May combine two claims.

There were significant effects of sex (p<0.001) and genotype (p=0.03) on total cerebrum ethanolamine plasmalogen, with a trending decrease in PLCG2 KO compared to WT mice (p=0.10).

“There were significant effects of sex (p<0.001) and genotype (p=0.03) on total cerebrum ethanolamine plasmalogen, with a trending decrease in PLCG2 KO compared to WT mice (p=0.10, Figure 3G).”

May combine two claims.

Pairwise differential gene expression analysis on the metadata revealed 17 differentially expressed genes between Plcg2 WT and KO and 14 between Plcg2 HET and KO.

“pairwise differential gene expression analysis on the metadata (including both brain regions and both sexes) revealed 17 differentially expressed genes (DEGs) between Plcg2 WT and KO (Figure 5D, Supplemental Dataset 3) and 14 DEGs between Plcg2 HET and KO using DESeq2 (Wald’s test, Benjamini Hochberg, p-adj<0.05) (Figure 5E, Supplemental Dataset 4).”

May combine two claims.

Shotgun lipidomics on brain cerebrum revealed major sex-specific alterations and relatively minor genotype effects at the whole lipidome level.

“Shotgun lipidomics on brain cerebrum revealed major sex-specific alterations and relatively minor genotype effects at the whole lipidome level (Figure S2A).”

May combine two claims.

Average litter sizes at birth (5.2 pups) and at weaning (4.6 mice) indicate that ~0.6 pups/litter died postnatally.

“Average litter sizes at birth (5.2 pups) and at weaning (4.6 mice) indicate that ~0.6 pups/litter died postnatally (Figure 1A).”

May combine two claims.

There were significant effects of genotype and sex on decreasing N- and OH-cerebrosides levels in the cerebrum, but only N-cerebrosides were significantly reduced in Plcg2 KO mice compared to WT and HET mice of both sexes.

“Further characterization revealed significant effects of genotype and sex on decreasing N- and OH-cerebrosides levels in the cerebrum (Figure 3B–C), but only N-cerebrosides were significantly reduced in Plcg2 KO mice compared to WT and HET mice of both sexes (Figure 3B).”

May combine two claims.

Genes coding for major myelin proteins (Mog, Cnp, Plp1) were significantly altered in metadata and/or sex-specific analysis, as well as other genes primarily expressed by oligodendrocytes (Fth1, Bcas1).

“Genes coding for major myelin proteins (Mog, Cnp, Plp1) were also significantly altered in metadata and/or sex-specific analysis, as well as other genes primarily expressed by oligodendrocytes (Fth1, Bcas1) (Figure 5J).”

May combine two claims.

Proteomics results identified 8 PLC family members in the mouse brain, with PLCβ1 being by far the most abundant one, and PLCγ2 being below detection limit.

“Our proteomics results identified 8 PLC family members in the mouse brain, with PLCβ1 being by far the most abundant one, and PLCγ2 being below detection limit.”

May combine two claims.

All weaned Plcg2 KO mice survived until three months of age and displayed normal body weights.

“Despite lower birth/weaning survival, all weaned Plcg2 KO mice survived until three months of age (end point of the study) and displayed normal body weights (Figure 1B).”

May combine two claims.

There was an interaction between sex and genotype in MAPK and PI3K related genes (p=0.028), T-cell signaling (p=0.046), and complement system genes (p=0.046).

“We also found interaction between sex and genotype in MAPK and PI3K related genes (p=0.028, Supplemental Figure 3D), T-cell signaling (p=0.046, Supplemental Figure 3E), and complement system genes (p=0.046, Supplemental Figure 3F).”

May combine two claims.

We observed an evident increase in the density of blood-filled vessels in Plcg2 KO intestines, that were thinner and more arborized than those of WT controls.

“Specifically, we observed an evident increase in the density of blood-filled vessels in Plcg2 KO intestines, that were thinner and more arborized than those of WT controls.”

May combine two claims.

There was a trending main effect of genotype on MAG area fraction (p=0.14) with KO mice showing less MAG labeling compared to WT (p=0.16) and HET (p=0.24).

“There was a trending main effect of genotype on MAG area fraction (p=0.14) with KO mice showing less MAG labeling compared to WT (p=0.16) and HET (p=0.24) (Figure 7D).”

May combine two claims.

PCA revealed differences in proteins due to mouse and/or sample effects outweigh differences due to genotype, indicating that Plcg2 depletion does not have major effects at the whole brain proteome level under physiological conditions in young adult mice.

“PCA revealed differences in proteins due to mouse and/or sample effects outweigh differences due to genotype (Figure 8A), indicating that Plcg2 depletion does not have major effects at the whole brain proteome level under physiological conditions in young adult mice.”

May combine two claims.

There were no changes in the area fraction of neuronal nuclei across any genotype, nor gross changes in NeuN distribution or morphology.

“We also evaluated changes in NeuN and did not observe any changes in the area fraction of neuronal nuclei across any genotype (Figure 7E) nor did we observe any gross changes in NeuN distribution or morphology.”

May combine two claims.

There was a main effect of sex and a Plcg2 gene-dose dependent trending decrease in total DAG in the cerebrum (p=0.076).

“We found a main effect of sex and a Plcg2 gene-dose dependent trending decrease in total DAG in the cerebrum (p=0.076, Figure 4A).”

May combine two claims.

Yields of Plcg2 KO mice were lower than expected based on theoretical Mendelian genetics (~25%) with females showing higher mortality rates than males.

“Yields of Plcg2 KO mice were lower than expected based on theoretical Mendelian genetics (~25%) with females showing higher mortality rates than males.”

May combine two claims.

Plcg2 HET mice displayed intermediate spleen weights and basal glucose levels for both sexes.

“Note that Plcg2 HET mice displayed intermediate spleen weights and basal glucose levels for both sexes.”

May combine two claims.

There were sex-specific effects on expression of oligodendrocyte (p<0.001), macrophages/microglia (p<0.001), and neuron (p<0.001) genes.

“There were also sex-specific effects on expression of oligodendrocyte (p<0.001, Supplemental Figure 3G), macrophages/microglia (p<0.001, Supplemental Figure 3H), and neuron (p<0.001, Supplemental Figure 3I) genes.”

May combine two claims.

KEGG pathway analysis using all differentially abundant proteins highlighted pathways relevant to aging and neurodegenerative disease, and alterations in amino acid metabolism and ribosome biogenesis.

“Furthermore, we performed KEGG pathway analysis using all DAPs to understand the biological processes that were perturbed across Plcg2 genotypes. The results highlighted a variety of pathways relevant to aging and neurodegenerative disease. Interestingly, the results also show evidence of alterations in amino acid metabolism and ribosome biogenesis (Fig. 8H).”

May combine two claims.

Volcano plots revealed 8 differentially abundant lipids between Plcg2 KO and WT, 10 between KO and HET, and no differentially abundant lipids between HT and KO females.

“Volcano plots revealed 8 differentially abundant lipids (DALs) (Benjamini, Krieger and Yekutieli adjusted p-value <0.05,) between Plcg2 KO and WT (Figure 2C), 10 DALs between KO and HET (Figure 2D), and no DALs between HT and KO females (Figure S2F).”

May combine two claims.

There was a significant main effect of genotype on genes related to homeostatic microglia (p=0.001), which were significantly reduced in female KO brains compared to WT/HT, and trended to decrease in male KOs.

“We found a significant main effect of genotype on genes related to homeostatic microglia (p=0.001, Supplemental Figure 3A), which were significantly reduced in female KO brains compared to those of WT/HT, and trended to decrease in male KOs.”

May combine two claims.

Gene expression of major myelin proteins (Mog, Cnp, Plp1) and other genes primarily expressed by oligodendrocytes (Fth1, Bcas1) were significantly altered in our Nanostring analysis.

“Consistent with our lipidomics and proteomics results, gene expression of major myelin proteins (Mog, Cnp, Plp1) and other genes primarily expressed by oligodendrocytes (Fth1, Bcas1) were also significantly altered in our Nanostring analysis.”

May combine two claims.

Our results show changes in other genes associated with AD (Bcas1, Abca1) and pathways associated with longevity (mTOR signaling).

“Notably, our results also show changes in other genes associated with AD (Bcas1, Abca1) and pathways associated with longevity (mTOR signaling).”

May combine two claims.

Our lipidomics results showed significant decreases in myelin-specific lipids (cerebrosides) and decreasing trends in myelin-enriched lipids (sulfatides and phosphatidylethanolamine plasmalogens) in Plcg2 KO mice.

“Surprisingly, our lipidomics results also showed significant decreases in myelin-specific lipids (i.e. cerebrosides) and decreasing trends in myelin-enriched lipids (i.e. sulfatides and phosphatidylethanolamine plasmalogens) in Plcg2 KO mice (Figure 3).”

May combine two claims.

Changes in microglia and T cells were in females and males respectively.

“Interestingly, changes in microglia and T cells were in females and males respectively”

May combine two claims.

We observed increases in complement and decreases in homeostatic microglia in female Plcg2 KO mice.

“We observed increases in complement and decreases in homeostatic microglia in female Plcg2 KO mice (Supplemental Figure 3A, 3F).”

May combine two claims.

Sexual dimorphism was pronounced in survival of Plcg2 KO mice, as well as our lipidomic analyses, with changes more pronounced in females.

“Sexual dimorphism was pronounced in survival of Plcg2 KO mice (Figure 1), as well as our lipidomic analyses, with changes more pronounced in females (Figure 2).”

May combine two claims.

Loss of PLCγ2 has subtle effects on brain homeostasis that may underlie enhanced vulnerability to AD pathology and aging via novel mechanisms in addition to regulation of microglia function.

“Overall, our data indicate that loss of PLCγ2 has subtle effects on brain homeostasis that may underlie enhanced vulnerability to AD pathology and aging via novel mechanisms in addition to regulation of microglia function.”

May combine two claims.

Loss of PLCγ2 would not only prevent PIP2 hydrolysis, but also prevent its synthesis, potentially explaining the observed overall reduction of PIP2 levels.

“Thus, loss of PLCγ2 would not only prevent PIP2 hydrolysis, but also prevent its synthesis, potentially explaining the observed overall reduction of PIP2 levels.”

• AssumptionRests on an assumption: PLCγ2 catalyzes the hydrolysis of PIP2 to DAG and IP3.

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

The cause of death was not determined but may be related to the previously described essential role of PLCγ2 in initiating the separation of the blood and lymphatic vasculature.

“The cause of death was not determined but may be related to the previously described essential role of PLCγ2 in initiating the separation of the blood and lymphatic vasculature (29).”

• cites [29] sourceNot checked — no full text of the source

Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

Compensatory reductions in expression of PLA2G4A, DGKE, or DAGL could explain our observed increase in PIP2.

“While we did not measure PLA2G4A, DGKE, or DAGL in our study, compensatory reductions in expression of these enzymes could explain our observed increase in PIP2.”

• AssumptionRests on an assumption: PLCγ2 catalyzes the hydrolysis of PIP2 to DAG and IP3.

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

The survival numbers are robust as they are based on 98 litters.

“These numbers are robust as they are based on 98 litters.”

May combine two claims.

Sex-specific analyses were underpowered and unadjusted.

“Note that sex-specific analyses were underpowered and unadjusted.”

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

Although internal bleeding likely explains early mortality, the mechanism(s) underlying the observed sex-specific mortality rates remain unclear.

“Although internal bleeding likely explains early mortality, the mechanism(s) underlying the observed sex-specific mortality rates remain unclear.”

May combine two claims.

Nanostring RNA expression profiles in Plcg2 WT and HET brains were virtually identical, while a subset of genes was differentially expressed in Plcg2 KO compared to Plcg2 WT and HET.

“Taken together our metadata analysis demonstrated that Nanostring RNA expression profiles in Plcg2 WT and HET brains were virtually identical, while a subset of genes was differentially expressed in Plcg2 KO compared to Plcg2 WT and HET.”

May combine two claims.

PLCγ2 is a major regulator of brain PIP2 homeostasis despite being expressed at relatively low levels in the brain compared to other family members.

“Considering that the PLC family is composed by 14 members (including 2 catalytically inactive members), these results suggest that PLCγ2 is a major regulator of brain PIP2 homeostasis despite being expressed at relatively low levels in the brain compared to other family members.”

• AssumptionRests on an assumption: PLCγ2 catalyzes the hydrolysis of PIP2 to DAG and IP3.

May combine two claims.

These results are in line with high levels of Plcg2 gene expression in spleen B-cells, suggestive of a potential role of Plcg2 in spleen homeostasis.

“These results are in line with high levels of Plcg2 gene expression in spleen B-cells (particularly in T1, T2 and follicular B-cells) (Gene Expression Commons), suggestive a potential role of Plcg2 in spleen homeostasis.”

• cites Gene Expression CommonsNot matched

  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).

A previous study reported marked decreases in the most mature B cell population in Plcg2 deficient mice.

“In fact, a previous study reported marked decreases in the most mature B cell population in Plcg2 deficient mice(30).”

• cites [30] D. Wang , et al., Phospholipase Cgamma2 is essential in the functions of B cell and several Fc receptors [In Process Citation]. Immunity 13 (2000). sourceNot checked — no full text of the source

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

Previous studies have reported internal hemorrhaging during development in other Plcg2 deficient mouse models, which have been proposed to be caused by rupture of blood-filled fragile lymphatic vessels by mechanical stress or pressure of the blood flow.

“Previous studies have reported internal hemorrhaging during development in other Plcg2 deficient mouse models (29, 30), which have been proposed to be caused by rupture of blood-filled fragile lymphatic vessels by mechanical stress or pressure of the blood flow (29).”

• cites [29] sourceNot checked — no full text of the source
• cites [30] D. Wang , et al., Phospholipase Cgamma2 is essential in the functions of B cell and several Fc receptors [In Process Citation]. Immunity 13 (2000). sourceNot checked — no full text of the source

May combine two claims.

The reduction in myelin lipids corresponds with the observed trending reduction of MAG by immunohistochemistry, which could result from altered oligodendrocyte homeostasis and/or myelin abnormalities.

“This reduction in myelin lipids corresponds with our observed trending reduction of MAG by immunohistochemistry, which could result from altered oligodendrocyte homeostasis and/or myelin abnormalities.”

May combine two claims.

Loss of PLCγ2 function has subtle but highly sexually dimorphic effects on brain homeostasis that may underlie enhanced vulnerability to AD pathology via microglia and myelin dysfunction.

“Overall, our data suggest that loss of PLCγ2 function has subtle but highly sexually dimorphic effects on brain homeostasis that may underlie enhanced vulnerability to AD pathology via microglia and, surprisingly, myelin dysfunction.”

Classified as probably not a substantial claim.

Mass spectrometry data was processed in Scaffold DIA filtered at 1% FDR using a minimum peptide count of 4.

“Mass spectrometry data was processed in Scaffold DIA (Proteome Software) filtered at 1% FDR using a minimum peptide count of 4.”

May combine two claims.

Loss of PLCγ2 alters microglia reactivity, potentially leading to downstream loss of myelin without strongly affecting neurons by the measures examined.

“Taken together with our lipidomic, gene expression, and histology data suggest that loss of PLCγ2 alters microglia reactivity, potentially leading to downstream loss of myelin without strongly affecting neurons by the measures we have examined.”

Classified as probably not a substantial claim.

Volcano plots were generated with GraphPad Prism using multiple t-tests with post-hoc FDR 5% (2-stage step-up method, Benjamini, Kieger Yekutieli).

“Volcano plots were generated with GraphPad Prism using multiple t-tests with post-hoc FDR 5% (2-stage step-up method, Benjamini, Kieger Yekutieli).”

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

Differences between our results and previously published results may be related to the age of the mice studied and methodological differences.

“Differences between our results and these previously published results may be related to the age of the mice studied and methodological differences, e.g. isolated microglia vs whole brain gene expression.”

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

Other cellular interactions may mediate the disruption of myelin lipids in Plcg2 KO mice.

“However, other cellular interactions may mediate the disruption of myelin lipids in Plcg2 KO mice.”