Rabbit Anti-Human FCGR2A Polyclonal antibody

The genetic background of primary Sjogren's syndrome (pSS) is partly shared with systemic lupus erythematosus (SLE). Immunoglobulin G Fc receptors are important for clearance of immune complexes. Fcg receptor variants and gene deletion have been found to confer SLE risk. In this study, four Fc gamma receptor single-nucleotide polymorphisms (SNPs) and one copy number variation (CNV) were studied. Swedish and Norwegian pSS patients (N = 527) and controls (N = 528) were genotyped for the Fc gamma receptor gene variant FCGR2A H131R (rs1801274) by the Illumina GoldenGate assay. FCGR3A F158V (rs396991) was analysed in 488 patients and 485 controls, FCGR3B rs447536 was analysed in 471 patients and 467 controls, and FCGR3B rs448740 was analysed in 478 cases and 455 controls, using TaqMan SNP genotyping assays. FCGR3B CNV was analysed in 124 patients and 139 controls using a TaqMan copy number assay. None of the SNPs showed any association with pSS. Also, no FCGR3B CNV association was detected. The lack of association of pSS with Fc gamma receptor gene variants indicates that defective immune complex clearance may not be as important in pSS pathogenesis as in SLE, and may point to important differences between SLE and pSS.

The role of the inflammatory mediator C-reactive protein (CRP) in atherosclerosis is recognized although its specific functions are not entirely clear. CRP binds to the Fc gamma receptor2A (Fc gamma R2A) and its polymorphism, FCGR2A (Arg131His), strongly influences the binding. We wanted to evaluate the CRP-mediated proatherogenic process on early atherosclerosis and investigated whether CRP and FCGR2A show an interactive effect on carotid intima-media thickness (IMT). Polymorphisms of FCGR2A (Arg131His) and CRP (-717A > G, -286C > T > A, +1059G > C, +1444C > T and +1846G > A) were genotyped and their effects on IMT were analyzed in 2260 young adults participating in the Cardiovascular Risk in Young Finns Study. CRP haplotypes were constructed based on the CRP polymorphisms. The FCGR2A(Arg131His) polymorphism did not have an independent effect on IMT but a significant gene-gene interaction, epistasis, between FCGR2A and CRP genetics on IMT was found. The epistatic effect was seen in men at haplotype and genotypic level; both CRP haplotype GCGCG (-717, -286, +1059, +1444 and +1846) and CRP -717A > G polymorphism interacted with FCGR2A(Arg131His) on IMT. After adjustment with classical risk factors the P-values for interaction were P = 0.013 and P = 0.010, respectively. No associations were observed in women. In conclusion, this study showed that the effect of CRP genetics on early atherosclerotic changes is modulated by the FCGR2A genetics.