Abstract:

Objective To investigate the changes of lymphocyte subsets in the elderly patients with severe sepsis before and after immune modulation therapy,and to provide the basis for curing the disease. Methods 76 patients older than 65 years were enrolled and randomly divided into control group (n=38) and treatment group (n=38).All patients were received conventional therapy and the patients in treatment group were received 1.6 mg thymosin alpha-1 through subcutaneous injection once a day for 15 d.20 healthy individuals older than 65 years were selected as healthy group.The lymphocyte subsets of objects in groups were measured before and after treatment. Results Before treatment,the ratios of CD3⁺,CD4⁺,Th1,CD4⁺/CD8⁺,CD19⁺,NK of the patients in control and treatment groups were significantly decreased and the ratios of Treg and CD8⁺ were significantly increased compared with healthy group(P<0.05 or P<0.01);the ratios of Th2 was mildly increased in the patients in various groups,but these parameters of the patients had no significant differences between control group and treatment group(P>0.05).After treatment,the ratios of CD3⁺,CD4⁺,and Th1 were significantly increased while the ratios of CD8⁺ was significantly decreased of the patients in treatment group compared with control group (P<0.05 or P<0.01);the ratios of CD4⁺/CD8⁺,CD19⁺,and NK cells were mildly increased while the ratios of Th2 and Treg were mildly decreased of the patients in treatment group compared with control group,but there was no statistically difference(P>0.05). Conclusion Compared with healthy aged persons,the lymphopenia and lymphocyte subsets imbalance exist in the elderly patients with severe sepsis.Thymosin alpha-1 can regulate the quantity and proportion of lymphocyte subsets in the elderly patients with severe sepsis.

Key words: elder, sepsis, lymphocyte subsets, immune modulation