NDT Advance Access originally published online on March 5, 2004
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Nephrol Dial Transplant (2004) 19: 1427-1431
Nephrol Dial Transplant Vol. 19 No. 6 © ERA-EDTA 2004; all rights reserved
Original Article
Fc
RIIa polymorphism: a susceptibility factor for immune complex-mediated lupus nephritis in Brazilian patients
1Division of Rheumatology and 2Division of Nephrology, University of São Paulo, São Paulo, Brazil and 3INSERM E-0225, Bichat Medical School, Paris, France
Correspondence and offprint requests to: R. C. Monteiro, INSERM E-0225, Bichat Medical School, 16, Rue Henri Huchard, F-75870, Paris, France and to E. Bonfa, rua Dr Arnaldo 455, University of São Paulo, 01246903 São Paulo, Brazil. Email: monteiro{at}bichat.inserm.fr
Background. Fc
RIIa is a low affinity receptor that has two co-dominantly expressed alleles, R131 and H131, which differ in their ability to bind immunoglobulin G (IgG) subclasses. Cells expressing H131 bind more efficiently complexed IgG2 and IgG3 than those expressing the R131 variant. The FcRIIa polymorphism has been shown to be associated with lupus nephritis. Here we evaluated the relevance of FcRIIa gene polymorphism in the development of lupus immune complex (IC)-mediated nephritis by comparing the genotype and allelic distribution of this receptor in lupus nephritis to ethnically matched healthy controls in Brazilians.
Methods. 119 systemic lupus erythematosus (SLE) patients and 48 healthy volunteers were recruited. FcRIIa genotyping was performed by PCR with allele-specific primers to distinguish between the two allelic forms (H131 and R131).
Results. Comparison of FcRIIa genotypes distribution in SLE patients with nephritis and in controls showed a significant increase in FcRIIa-R131 homozygosity (P 
0.02). The genotype distribution in lupus nephritis (45% with FcRIIa-R/R131, 30% with H/R131 and 25% with H/H131) was distinct from that observed in controls (21% with FcRIIa-R/R131, 52% with H/R131 and 27% with H/H131). In contrast, there was no difference in the distribution of FcRIIa genotypes in lupus without nephritis and controls (P = 0.3). Reinforcing the relevance of FcRIIa polymorphism in IC-mediated nephritis, patients with renal failure had an over-representation of the R131 allele (70%) when compared with normal controls (47%) (P = 0.06).
Conclusions. The skewed distribution of FcRIIa genotypes with the predominance of homozygous R/R131 genotype observed in lupus nephritis emphasizes its importance as a heritable risk factor for IC-mediated renal injury in Brazilian lupus patients.
Keywords: autoimmunity; Fc receptors; glomerulonephritis; immunoglobulin; systemic lupus erythematosus
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  M. Mackay, A. Stanevsky, T. Wang, C. Aranow, M. Li, S. Koenig, J. V. Ravetch, and B. Diamond Selective dysregulation of the Fc{gamma}IIB receptor on memory B cells in SLE J. Exp. Med., September 4, 2006; 203(9): 2157 - 2164. [Abstract] [Full Text] [PDF]
|
|