Maintaining the immunological balance in parasitic infections:: A role for TGF-β?

Transforming growth factor beta (TGF-beta) is an important regulator of inflammation, being proinflammatory at low concentrations and anti-inflammatory at high concentration ions. As such, TGF-beta might be important in maintaining the balance between control and clearance of infections organisms on the one hand and prevention of immune-mediated pathology on the other. In this article, Fakhereldin Omer, Jorgen Kurtzhals and Eleanor Riley review the immunoregulatory properties of TGF-beta in the context of parasitic infections. Data from murine malaria infections suggest that TGF-beta modifies the severity of the disease, and a number of potential protective mechanisms are discussed. Evidence is accumulating that TGF-beta is important for the regulation of other host-parasite interactions and that parasites might directly influence TGF-beta-dependent pathways via the synthesis of TGF-beta or TGF-beta-receptor homologies.