Anti-FCGR2A monoclonal antibody, clone FQS7768(3)

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.

Objective Systemic lupus erythematosus is a clinically heterogeneous autoimmune disease. A number of genetic loci that increase lupus susceptibility have been established. This study examines if these genetic loci also contribute to the clinical heterogeneity in lupus. Materials and methods 4001 European-derived, 1547 Hispanic, 1590 African-American and 1191 Asian lupus patients were genotyped for 16 confirmed lupus susceptibility loci. Ancestry informative markers were genotyped to calculate and adjust for admixture. The association between the risk allele in each locus was determined and compared in patients with and without the various clinical manifestations included in the ACR criteria. Results Renal disorder was significantly correlated with the lupus risk allele in ITGAM (p=5.0 x 10(-6), OR 1.25, 95% CI 1.12 to 1.35) and in TNFSF4 (p=0.0013, OR 1.14, 95% CI 1.07 to 1.25). Other significant findings include the association between risk alleles in FCGR2A and malar rash (p= 0.0031, OR 1.11, 95% CI 1.17 to 1.33), ITGAM and discoid rash (p= 0.0020, OR 1.20, 95% CI 1.06 to 1.33), STAT4 and protection from oral ulcers (p= 0.0027, OR 0.89, 95% CI 0.83 to 0.96) and IL21 and haematological disorder (p= 0.0027, OR 1.13, 95% CI 1.04 to 1.22). All these associations are significant with a false discovery rate of < 0.05 and pass the significance threshold using Bonferroni correction for multiple testing. Conclusion Significant associations were found between lupus clinical manifestations and the FCGR2A, ITGAM, STAT4, TNSF4 and IL21 genes. The findings suggest that genetic profiling might be a useful tool to predict disease manifestations in lupus patients in the future.