Genetic determinants in hepatitis C virus-associated mixed cryoglobulinemia: role of polymorphic variants of BAFF promoter and Fcγ receptors.
Arthritis Rheum
; 63(5): 1446-51, 2011 May.
Article
en En
| MEDLINE
| ID: mdl-21538321
ABSTRACT
OBJECTIVE:
Mixed cryoglobulinemia (MC) is a hepatitis C virus (HCV)-related immune complex disorder. Only some HCV-infected patients develop MC, which suggests that the genetic background of the host plays a key role. This study was undertaken to evaluate the contribution of host genetic factors in the pathogenesis of HCV-associated MC (HCV-MC) by analyzing allelic variants of low-affinity Fcγ receptor (FcγR) genes and BAFF promoter.METHODS:
FcγR polymorphisms (FCGR2A 131 R/H, FCGR2B 232 I/T, FCGR3A 176 V/F, and FCGR3B NA1/NA2) and BAFF promoter polymorphism -871 C/T were analyzed in 102 patients with HCV-MC and 108 patients with HCV without MC, using polymerase chain reaction-based techniques.RESULTS:
A higher prevalence of -871 T/T homozygosity (31% versus 16%; P = 0.001) and a greater frequency of T alleles of the BAFF promoter (80% versus 57%; P = 0.004) were found in the HCV-MC group than in the HCV group. A significant increase in serum BAFF concentration was significantly associated with the higher frequency of the T allele in HCV-MC (mean ± SD 4.12 ± 1.29 versus 2.09 ± 0.81 ng/ml; P < 0.0005). The distribution of the FcγR genotypes was not significantly different. In the 21 HCV-MC patients treated with rituximab, the response was strictly related to F allele homozygosity (significantly reduced in 5 of 5 patients with the FCGR3A F/F genotype versus 4 of 16 with V/V or V/F; P < 0.0005).CONCLUSION:
These results indicate the importance of host genetic background in the development of HCV-MC, suggesting that mechanisms enhancing Ig production and B cell survival may play a relevant role. Genetic FcγR variants seem to be crucial to the effectiveness of rituximab therapy.
Texto completo:
1
Colección:
01-internacional
Asunto principal:
Hepatitis C
/
Receptores de IgG
/
Hepacivirus
/
Crioglobulinemia
/
Factor Activador de Células B
Tipo de estudio:
Risk_factors_studies
Límite:
Adult
/
Aged
/
Aged80
/
Humans
/
Middle aged
Idioma:
En
Revista:
Arthritis Rheum
Año:
2011
Tipo del documento:
Article
País de afiliación:
Italia