The expression of CD38 on CD4+ T cells in peripheral blood of patients with severe acute respiratory syndrome

Objective To investigate the expression of CD38 on CD4+T cells in the peripheral blood of patients with severe acute respiratory syndrome (SARS) as well as their relationship to the severity of the disease.Methods Peripheral blood samples from 157 cases of severe acute respiratory syndrome (SARS), 37 cases of mycoplasma pneumonia infection and 38 healthy adult volunteers were measured for the percentage of CD4+T cell of lymphocytes and the expression of CD 38 on CD4+cell by dual-color flow cytometry.Results SARS patients did not differ from healthy volunteers in CD4+ cell percentage, but CD38 positive rate of CD4+ cell(CD38/CD4%) and mean fluorescent intensity of CD38( CD38MF) of SARS patients were significantly lower than those of health control respectively(P0.05, P0.05).CD38/CD4% of severe patients was significantly lower than that of mild ones.CD4% in SARS was significantly higher than that in mycoplasma pneumonia infection patients(P0.01),but CD38/CD4% and CD38MF were much lower than in mycoplasma pneumonia infection(P0.01, P0.01).Conclusion The expression of CD38 on CD4+ T cells was down regulated and correlated with the severity of SARS patients. The alteration of CD38 expression on CD4+ T cells was quite different between SARS and mycoplasma pneumonia infection.The monitoring of CD38 on CD4+ was useful in the differentiation of SARS and mycoplasma pneumonia infection.