In summary, FcgRI knockdown downregulated kidney inflammation and fibrosis and FcgRIIb knockout accelerated inflammation, fibrosis, and the anomalous deposition of oxLDL whereas FcgRIII deficiency failed to protect kidney from diabetic renal injury.
The role of Fc receptors in the induction and progression of Crgn is increasingly recognized, and our previous studies have shown that copy number variation in Fcgr3 partially explains the genetic susceptibility of the Wistar-Kyoto (WKY) rat to nephrotoxic nephritis, a rat model of Crgn.
The FcgammaRIIIa F/F genotype was also associated with nephritis (WHO class III and IV, P = 0.04 for the SLE group) and in combination with the CRP4 A-allele a stronger association was noted (P < 0.001).
In the nephritis group (n = 46), as well as the entire SLE cohort, there was a predominance of genotypes with low-binding alleles (FcgammaRIIa-R131 and FcgammaRIIIa-F176) at both loci (SLE nephritis patients 89% versus controls 62%; P < 0.002; odds ratio 0.20 [95% confidence interval 0.05-0.6] for risk of nephritis in individuals homozygous for either FcgammaRIIa-H131 or FcgammaRIIIaV176).
There was no skewing in FcgammaRIIa or FcgammaRIIIa genotypes between female SLE and female controls, but FcgammaRIIa-R131 allele showed skewing between female SLE with nephritis and female SLE without nephritis.
Univariate and multivariate analyses demonstrated a striking association between the low-affinity FcgammaRIIIA-158F allele and FF genotype and the risk of nephritis among Caucasians, but not among non-Caucasians (multivariate odds ratio [OR] 2.6 for Caucasians with FF genotype), (P = 0.0017).
Specifically, a polymorphism of FC gamma RIII, termed Fc gamma RIIIA-158F, has been found to be associated with SLE in 2 largely Caucasian populations and appeared to constitute a risk factor for nephritis.