ABSTRACT
Objective:Autoimmune mechanisms, including cellular and humoral immune, are likely to participate in the pathogenesis of at least a subgroup of idiopathic dilated cardiomyopathy(IDC), in which cellular immune-mediated one plays a more important role. Cytotoxic T lymphocyte associated antigen-4(CTLA-4) is the major negative regulatory factor of cellular immunity. This study was conducted to investigate the association of CTLA-4 gene promoter -318C/T polymorphism, exon 1 A/G polymorphism and 3′ untranslated region microsatellite polymorphism with susceptibility to IDC in Han Chinese.Methods:Polymerase chain reaction-restriction fragment length polymorphisms(PCR-RFLP) techniques were used to analyze the polymorphisms of CTLA-4 promoter -318, exon 1 A/G and 3′ untranslated region in the unrelated Han ethnic population in Heilongjiang Province(including 72 IDC patients and 100 normal controls). Serum sCTLA-4 was tested by ELISA. The relationship of CTLA-4 genotype and alleles frequencies with sCTLA-4 was evaluated by linear regression analysis.Results:Compared with controls, the frequencies of GG genotype(0.604 2 and 0.739 6, P=0.012) and the G allele(0.360 0 and 0.560 0, P=0.008) were significantly increased in patients with IDC. Increased serum sCTLA-4 was found in the IDC group compared with the controls[(1.87?1.06)?g/L vs (0.54?0.19)?g/L, P