Cytokines Interleukin 4 (IL-4) and Interleukin 10 (IL-10) Gene Polymorphisms as Potential Host Susceptibility Factors in Virus-Induced Encephalitis

Yu, Ying; Chen, Ying; Wang, Feng-Ling; Sun, Jing; Li, Hai-Jun; Liu, Jia-Ming

Interleukin 4 (IL-4) and interleukin 10 (IL-10), are 2 cytokines that have been found to have strong links to encephalitis [15] [16] [17] . It has been suggested that IL-4 is crucial to the induction of the naive helper T (Th0) cells differentiating to type 2 helper T (Th2) cells [18, 19] . IL-4 is known to have 2 different receptor complexes: the IL-4Ra chain and the gc chain [20] . IL-4 has a role in maintaining physiological balance and repairing tissues [21] . Moreover, IL-4 has exhibited in anti-inflammatory functions. IL-4 derived by activated CD4+ T cells can promote allergic responses [20, 22, 23] . Additionally, IL-10 is a cytokine produced by T cells, B cells, and macrophages, exhibiting a role in anti-inflammation and immunosuppression [24] [25] [26] . Virusinduced encephalitis is reported to respond to IL-10 [27] . IL-4 and IL-10 gene polymorphisms have been widely investigated in inflammatory diseases, such as asthma, chronic polyarthritis, rhinovirus bronchiolitis, and type 2 diabetes mellitus (T2DM) [28] [29] [30] [31] . Patients previously diagnosed with virusinduced encephalitis formed the basis of the experimental exploration of this study. The IL-4 and IL-10 gene polymorphisms and their correlation to virus-induced encephalitis susceptibility, through direct sequencing, were analyzed during the study.