Copy number of FCGR3B, which is associated with systemic lupus erythematosus, correlates with protein expression and immune complex uptake.

Copy number (CN) variation (CNV) has been shown to be common in regions of the genome coding for immune-related genes, and thus impacts upon polygenic autoimmunity. Low CN of FCGR3B has recently been associated with systemic lupus erythematosus (SLE). FcgammaRIIIb is a glycosylphosphatidylinositol-linked, low affinity receptor for IgG found predominantly on human neutrophils. We present novel data demonstrating that both in a family with FcgammaRIIIb-deficiency and in the normal population, FCGR3B CNV correlates with protein expression, with neutrophil uptake of and adherence to immune complexes, and with soluble serum FcgammaRIIIb. Reduced FcgammaRIIIb expression is thus likely to contribute to the impaired clearance of immune complexes, which is a feature of SLE, explaining the association between low FCGR3B CNV and SLE that we have confirmed in a Caucasian population. In contrast, antineutrophil cytoplasmic antibody-associated systemic vasculitis (AASV), a disease not associated with immune complex deposition, is associated with high FCGR3B CN. Thus, we define a role for FCGR3B CNV in immune complex clearance, a function that may explain why low FCGR3B CNV is associated with SLE, but not AASV. This is the first report of an association between disease-related gene CNV and variation in protein expression and function that may contribute to autoimmune disease susceptibility

Retrospective evaluation of whole exome and genome mutation calls in 746 cancer samples

Funder: NCI U24CA211006Abstract: The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) curated consensus somatic mutation calls using whole exome sequencing (WES) and whole genome sequencing (WGS), respectively. Here, as part of the ICGC/TCGA Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium, which aggregated whole genome sequencing data from 2,658 cancers across 38 tumour types, we compare WES and WGS side-by-side from 746 TCGA samples, finding that ~80% of mutations overlap in covered exonic regions. We estimate that low variant allele fraction (VAF < 15%) and clonal heterogeneity contribute up to 68% of private WGS mutations and 71% of private WES mutations. We observe that ~30% of private WGS mutations trace to mutations identified by a single variant caller in WES consensus efforts. WGS captures both ~50% more variation in exonic regions and un-observed mutations in loci with variable GC-content. Together, our analysis highlights technological divergences between two reproducible somatic variant detection efforts

31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two

Background The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd. Methods We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background. Results First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001). Conclusions In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival

Copy number of which is associated with systemic lupus erythematosus, correlates with protein expression and immune complex uptake-5

plate are shown (all of the raw data are shown in Fig. S1, A and B). The horizontal bar indicates the mean. The P values shown indicate comparison of all cases and controls using a stratified Student's test. (A) UK SLE patients, = 171; UK controls, = 176. (B) Hong Kong SLE patients, = 159; Hong Kong controls, = 150.<p><b>Copyright information:</b></p><p>Taken from "Copy number of which is associated with systemic lupus erythematosus, correlates with protein expression and immune complex uptake"</p><p></p><p>The Journal of Experimental Medicine 2008;205(7):1573-1582.</p><p>Published online 7 Jul 2008</p><p>PMCID:PMC2442635.</p><p></p

QPCR was used to determine ratios in normal controls and cohorts of patients with AASV (cohorts described in Supplemental materials and methods)

In each case, results from one representative qPCR plate are shown (all of the raw data are shown in Fig. S1 C). The horizontal bar indicates the mean. P values shown for each cohort indicate comparison of all cases and controls using a stratified Student's test. (A–C) AASV versus control in three independent UK cohorts. (D) Single plate of SLE and AASV, compared using a Student's test. Supplemental materials and methods and Fig. S1 C are available at .<p><b>Copyright information:</b></p><p>Taken from "Copy number of which is associated with systemic lupus erythematosus, correlates with protein expression and immune complex uptake"</p><p></p><p>The Journal of Experimental Medicine 2008;205(7):1573-1582.</p><p>Published online 7 Jul 2008</p><p>PMCID:PMC2442635.</p><p></p