CD4 and schistosomiasis: CD3+ CD4+ CD25hi T regulatory cells (Treg) are elevated in individuals with schistosomiasis [46], leading us to ask if those in our study had elevated levels of CD3+ CD4+ CD25hi Treg, and if their Treg levels correlated with their antibody responses and for those who were Sm+ if their levels changed after treatment with praziquantel (PZQ).