CTLA-4 exon 1 +49 polymorphism alone and in a haplotype with −318 promoter polymorphism may confer susceptibility to chronic HBV infection in Chinese Han patients
Cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) plays a pivotal role in regulating T cell activation, which is believably critical for the outcome of hepatitis B virus (HBV) infection. The expression and function of CTLA-4 may be affected by gene polymorphisms. This study investigated the influence of CTLA-4 polymorphisms on disease susceptibility in Chinese Han patients with chronic HBV infection. CTLA-4 +49A/G and −318C/T polymorphisms were evaluated by DNA amplification with polymerase chain reaction followed by the restriction fragment length polymorphism analysis. The patients with chronic HBV infection had higher frequencies of genotype AA and allele A of CTLA-4 +49A/G polymorphism. The haplotype +49A−318C was significantly over-represented (P < 0.001) and haplotype +49G−318C under-represented (P = 0.006) in the patients. The +49GG genotype was more frequent (P = 0.009) and +49A allele was less frequent in patients with lower ALT levels (P = 0.012) in HBeAg positive chronic hepatitis B. It is indicated that CTLA-4 +49A/G polymorphism alone and in a haplotype with −318C allele may confer susceptibility to chronic HBV infection in Chinese Han patients.
KeywordsChronic HBV infection CTLA-4 Genetic polymorphism Association
This work was supported in part by funding from National Natural Science Foundation of China (Grant no. 30972758). We thank Dr. Bofeng Zhu and Chunxia Yan from the Department of Forensic Science, School of Medicine, Xi’an Jiaotong University, for assistance in statistical analysis. We thank Dr. Ostabela Mutashaga for English editing of the manuscript.
Conflict of interest statement
The authors declare that they have no conflict of interest related to the publication of this manuscript.
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