[Study on immune status of patients with schistosomiasis japonica in Poyang Lake region II characterization of cellular immune in schistosomiasis patients].

Objective: To observe the characterization of cellular immune of schistosomiasis japonica patients in low endemic area of Poyang Lake region.

Methods: The schistosomiasis patients who were positive by stool detections were selected as study subjects, and the individuals who were negative by stool detections in three consecutive years were selected as negative controls. The CD4+T cell, CD8+T cell and CD4+CD25+Treg in venous blood of the study subjects were detected by using flow cytometry. In vitro, cytokine (IFN-gamma and IL-10) production of PBMC in response to soluble egg antigen (SEA) and soluble worm antigen preparation (SWA) were measured by ELISA.

Results: The levels of CD4+CD25+Treg in individuals who were positive by stool detections (5.99 +/- 1.60)% were higher than those of the negative (5.04 +/- 1.64)%, and the difference was significant (t = 3.261, P < 0.01). One year after the treatment, the levels of IFN-gamma were significantly higher (Stimulated by SEA before and after the treatment, the mean levels were 121.97 and 2 564.03 pg/ml, respectively; stimulated by SWA before and after treatment, the mean levels were 102.89 and 646.26 pg/ml, respectively) and IL-10 were significant lower in patients who were positive by stool detections (Stimulated by SEA before and after treatment, the mean level were 294.75 and 122.43 pg/ml, respectively; stimulated by SWAP before and after treatment, the mean cytokine levels were 110.10 and 31.85 pg/ml, respectively).

Conclusion: The increase of induced CD4+CD25+Treg is one of causes that down-regulate cellular immune of human body after infection with Schistosoma japonicum.