title: Association of MICA gene polymorphisms with liver fibrosis in schistosomiasis patients in the Dongting Lake region.
abstract: Major histocompatibility complex class I chain-related A (MICA) is a highly polymorphic gene located within the MHC class I region of the human genome. Expressed as a cell surface glycoprotein, MICA modulates immune surveillance by binding to its cognate receptor on natural killer cells, NKG2D, and its genetic polymorphisms have been recently associated with susceptibility to some infectious diseases. We determined whether MICA polymorphisms were associated with the high rate of Schistosoma parasitic worm infection or severity of disease outcome in the Dongting Lake region of Hunan Province, China. Polymerase chain reaction-sequence specific priming (PCR-SSP) and sequencing-based typing (SBT) were applied for high-resolution allele typing of schistosomiasis cases (N = 103, age range = 36.2-80.5 years, 64 males and 39 females) and healthy controls (N = 141, age range = 28.6-73.3 years, 73 males and 68 females). Fourteen MICA alleles and five short-tandem repeat (STR) alleles were identified among the two populations. Three (MICA*012:01/02, MICA*017 and MICA*027) showed a higher frequency in healthy controls than in schistosomiasis patients, but the difference was not significantly correlated with susceptibility to S. japonicum infection (Pc > 0.05). In contrast, higher MICA*A5 allele frequency was significantly correlated with advanced liver fibrosis (Pc < 0.05). Furthermore, the distribution profile of MICA alleles in this Hunan Han population was significantly different from those published for Korean, Thai, American-Caucasian, and Afro-American populations (P < 0.01), but similar to other Han populations within China (P > 0.05). This study provides the initial evidence that MICA genetic polymorphisms may underlie the severity of liver fibrosis occurring in schistosomiasis patients from the Dongting Lake region.
authors.affiliation: Department of Immunology, College of Basic Medical Sciences, Central South University, 110 Xiangya Road, Changsha, Hunan Province, China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Gong
authors.forename: Qi-Zhi
authors.initials: QZ
authors.lastname: Luo
authors.forename: Lin
authors.initials: L
authors.lastname: Lin
authors.forename: Yu-Ping
authors.initials: YP
authors.lastname: Su
authors.forename: Hai-Bo
authors.initials: HB
authors.lastname: Peng
authors.forename: Kun
authors.initials: K
authors.lastname: Du
authors.forename: Ping
authors.initials: P
authors.lastname: Yu
authors.forename: Shi-Ping
authors.initials: SP
authors.lastname: Wang
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D002681:China; D015331:Cohort Studies; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005838:Genotype; D015395:Histocompatibility Antigens Class I / Q000235:genetics*; D006801:Humans; D008103:Liver Cirrhosis / Q000235:genetics / Q000469:parasitology*; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic / Q000235:genetics*; D012552:Schistosomiasis / Q000150:complications* / Q000235:genetics; D012720:Severity of Illness Index
chemical_list: D015395:Histocompatibility Antigens Class I; C099187:MHC class I-related chain A