Abstract: 【Abstract】Objective To explore the pathogenesis of hand-foot-mouth disease(HFMD)，the changes of lymphocyte T subsets and the level of serum interleukin-6 (IL-6) and interleukin-10 (IL-10) were determined. Methods The changes of lymphocyte T subsets(CD3+、CD4+、CD8+、NK、CD4+/CD8+) and the level of serum IL-6，IL-10 were assayed in 82 patients of HFMD and 30 normal controls respectively by flow cytometry and by enzyme-linked immuno sorbent assay(ELISA). Results Simple cases of HFMD compared with control group: The percentages of lymphocyte CD3+,CD4+ were significantly reduced（p<0.01）, and no significant difference was observed in the percentages of CD8+, natural killer(NK)cells and the ratio of CD4+/CD8+ between simple patients and controls(P>0.05). The ratio of lymphocyte B showed significant increases（p<0.01）, while serum IL-6，IL-10 were detected no significant difference among simple cases and controls（p>0.05）; Severe cases of HFMD compared with control group: The percentages of lymphocyte CD3+,CD4+ and the ratio of CD4+/CD8+ were significantly reduced（p<0.01）, and no significant difference was observed in the percentages of CD8+ and NK cells between severe cases and controls（p>0.05）. The ratio of lymphocyte B and serum IL-6, IL-10 showed significant increases（p<0.01）. The results of severe cases compared with simple cases were similar to compared with controls. Conclution Lymphocyte T in children with HFMD appearred relatively inhibition in varying degrees, lymphocyte B proliferation in response ,and cytokines excessively secretion. The above indicated that the immunity of children with HFMD, especially severe cases, existed dysfunction obviously.

Key words: Hand-foot-mouth disease, lymphocyte subsets, Interleukin-6(IL-6), Interleukin-10(IL-10), Flow cytometry