Project description:Complement C3aR is primarily expressed in microglial cells in the brain. Our study found elevated expression of C3aR in microglia in Alzheimer's disease. To understand the underlying molecular mechanism, we sorted microglia based on their C3aR expression from 9-month-old wild-type and APP-KI mice. Through RNA-seq analysis, we identified metabolic perturbations in C3aR-positive microglia from 9-month-old APP-KI mice. Furthermore, we performed RNA-seq on sorted microglial cells from wild-type, C3aR knockout, APP-KI, and APP-KI;C3aR knockout mice. This analysis revealed a dampening of metabolic dysfunction in the absence of C3aR.
Project description:Diabetic nephropathy (DN) is the leading cause of chronic kidney disease and end-stage renal disease. Emerging evidence suggests that complement activation is involved in the pathogenesis of DN. The aim of this study was to investigate the pathogenic role of C3a and C3a receptor (C3aR) in DN. The expression of C3aR was examined in the renal specimen of DN patients. Using a C3aR gene knockout mice (C3aR-/-), we evaluated kidney injury in diabetic mice. The mouse gene expression microarray was performed to further explore the pathogenic role of C3aR. Then the underlying mechanism was investigated in vitro with macrophage treated with C3a. Compared with normal controls, the renal expression of C3aR was significantly increased in DN patients. C3aR-/- diabetic mice developed less severe diabetic renal damage compared with WT diabetic mice, exhibiting significantly lower level of albuminuria and milder renal pathological injury. Microarray profiling uncovered significantly suppressed inflammatory responses and T cell adaptive immunity in C3aR-/- diabetic mice compared with WT diabetic mice and this result was further verified by immunohistochemical staining of renal CD4+, CD8+ T cells and macrophages infiltration. In vitro study demonstrated C3a can enhance macrophages secreted cytokines which could induce inflammatory responses and differentiation of T cell lineage. In conclusion, C3aR deficiency could attenuate diabetic renal damage through suppressing inflammatory responses and T cell adaptive immunity, possibly by influencing macrophages secreted cytokines. Thus, C3aR may be a promising therapeutic target for DN.
Project description:Diabetic nephropathy (DN) is the leading cause of chronic kidney disease and end-stage renal disease. Emerging evidence suggests that complement activation is involved in the pathogenesis of DN. The aim of this study was to investigate the pathogenic role of C3a and C3a receptor (C3aR) in DN. The expression of C3aR was examined in the renal specimen of DN patients. Using a C3aR gene knockout mice (C3aR-/-), we evaluated kidney injury in diabetic mice. The mouse gene expression microarray was performed to further explore the pathogenic role of C3aR. Then the underlying mechanism was investigated in vitro with macrophage treated with C3a. Compared with normal controls, the renal expression of C3aR was significantly increased in DN patients. C3aR-/- diabetic mice developed less severe diabetic renal damage compared with WT diabetic mice, exhibiting significantly lower level of albuminuria and milder renal pathological injury. Microarray profiling uncovered significantly suppressed inflammatory responses and T cell adaptive immunity in C3aR-/- diabetic mice compared with WT diabetic mice and this result was further verified by immunohistochemical staining of renal CD4+, CD8+ T cells and macrophages infiltration. In vitro study demonstrated C3a can enhance macrophages secreted cytokines which could induce inflammatory responses and differentiation of T cell lineage. In conclusion, C3aR deficiency could attenuate diabetic renal damage through suppressing inflammatory responses and T cell adaptive immunity, possibly by influencing macrophages secreted cytokines. Thus, C3aR may be a promising therapeutic target for DN.
Project description:Regeneration of skeletal muscle following injury is accompanied by transient inflammation initiation and resolution. However, it is unclear what signals control these processes. To better understand the biological pathways by C3a-C3aR activation in monocyte druing muscle regeneration,we examined global transcriptional changes in macrophages from the muscle after CTX injury.Male C57BL/6J mice were used at 12 weeks of age. 30 ul 10uM Cardiotoxin (CTX) was injected to TA muscle to injury muscle. CD11b+ cells was isolated from WT and C3aR-/- muscle at 1 day after CTX injury by FACS , then total RNA obtained from these cells were used for the analysis of RNA-seq.
Project description:Several lines of evidence suggest that inflammation plays a pivotal role in the development and progression of CRC and can be unleashed by the loss of innate immunosurveillance. The complement system is a well characterized first line of defense against pathogens and a central component of the immune responses. As such, the complement system is an important determinant in the maintenance of intestinal homeostasis and emerging evidences suggest that complement dysregulation is involved in the development and progression of CRC. Here we show that in CRC patients CpG island methylation occurs in the gene encoding for the complement anaphylatoxin C3a receptor (c3aR) and strong C3aR down-regulation resulted in decreased overall survival and events-free survival in CRC patients. Ablation of c3ar in mouse models of CRC resulted in the establishment of a pro-inflammatory microbial flora, which fostered strong Th1/Th17 immune responses and a striking increase in tumor incidence and growth that were both dependent on the microbiota. Our findings highlight a previously unrecognized tumor oncosuppressive role for C3aR in CRC that could be exploited as a biomarker for more effective therapeutic intervention.
Project description:Complement has emerged as a component of tumor promoting inflammation. We conducted a systematic assessment of the role of complement activation and effector pathways in sarcomas. C3-/-, MBL1/2-/- and C4-/- mice showed reduced susceptibility to 3-methylcholanthrene sarcomagenesis and transplanted sarcomas, whereas C1q and factor B deficiency had marginal effects. Complement 3a receptor (C3aR), but not C5aR1 and C5aR2, deficiency mirrored the phenotype of C3-/- mice. C3 and C3aR deficiency were associated with reduced accumulation and functional skewing of tumor-associated macrophages, increased T cell activation and response to anti-PD-1 therapy. Transcriptional profiling of sarcoma infiltrating macrophages and monocytes revealed the enrichment of MHC II-dependent antigen presentation pathway in C3-deficient cells. In patients, C3aR expression correlated with a macrophage population signature and C3 deficiency-associated signatures predicted better clinical outcome. These results suggest that the lectin pathway and C3a/C3aR axis are key components of complement and macrophage-mediated sarcoma promotion and immunosuppression.
Project description:RNAseq was performed by to compare gene expression between wildtype and Smchd1 KO ES cells, the gene expression pattern in Dux KO mutants , Double KO mutant Tet-TKO mutants and Tet TKO plus SMCKHD1 KO mutants were analyzed by RNAseq.
Project description:RNAseq was used to identify host and EBV viral transcriptome changes in CHAF1B knock-out Akata EBV+ cells. CHAF1B KO Akata EBV+ cells were subjected to RNAseq analysis. The Akata EBV+ cells expressing control sgRNA was used as the control.