Genetic polymorphism of CCL2-2518, CXCL10-201, IL8+781 and susceptibility to severity of Enterovirus-71 infection in a Chinese population

The goal of this study was to examine the relationship between CCL2-2518A/G, CXCL10-201A/G, and IL8+781C/T gene polymorphism and severity of Enterovirus 71 (EV71) infection in a Chinese population. A case-control study was conducted to compare the distribution of genotype and genetic frequency of the CCL2-2518A/G, CXCL10-201A/G, and IL8+781C/T gene polymorphisms among EV71-infected patients (n = 186), including mild cases (n = 103), severe cases (n = 83) and healthy control subjects (n = 233) with polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and analyzed the relationship between the CCL2-2518A/G, CXCL10-201A/G, and IL8+781C/T gene polymorphism and the susceptibility to EV71 infection. No significant differences were found in the distribution of genotype CCL2-2518A/G, CXCL10-201A/G, and IL8+781C/T between the healthy control group and EV71-infected patients. However, three SNPs were associated with severity of EV71 infection: the G allele (genotypes AG or GG) in the CCL2-2518A/G (OR 2.34, 95 % CI 1.50-3.65, P < 0.001), the A allele (genotypes AA or AG) in the CXCL10-201A/G (OR 3.60, 95 % CI 1.73-7.47, P < 0.001), and the C allele (genotypes CC or CT) in the IL8+781C/T (OR 2.63, 95 % CI 1.67-4.13, P < 0.001) were more frequent in patients with severe EV71 infection. No significant difference was observed between EV71 encephalitis and severe cases. At the same time, there were significant differences in fever days, WBC, CRP and BG concentration, and CCL2, CXCL10 and IL-8 levels according to the three SNPs among 186 EV71-infected patients, but no significant differences were observed in gender, age, ALT, AST, CK-MB, and CSF evaluations. The G carrier of the CCL2-2518A/G, the A carrier of the CXCL10-201A/G, and the C carrier of the IL8+781C/T were found to be associated with severity of EV71 infection, and could be susceptibility factors in the development of EV71 infection in the Chinese population.