CD4 and schistosomiasis: Comparing whole blood from subjects with schistosomiasis by direct immunofluorescent staining for expression of CD3, CD4, FoxP3, CD25hi, and CD127, we compared different cell surface marker combinations that have been used to define Treg cells.9,23,24 We found that the percentages of CD4+/FoxP3 + lymphocytes did not differ from those of CD4+/CD25hi lymphocytes (P = 0.339).