IL10 and helminthiasis: More recently, studies characterising cellular responses have suggested the existence of a regulatory subset of T cells (Treg), which modulate the effects of Th1 and Th2 responses through the immunosuppressive cytokines interleukin-10 (IL-10) and transforming growth factor beta (TGF-β) (13) and have suggested that it is the balance between Th1, Th2 and Treg responses, which determines the outcome of helminth infections [reviewed in (14)].