MODULATING ONGOING TH2-CELL RESPONSES IN EXPERIMENTAL LEISHMANIASIS

Dramatically polarized T helper (Th)-cell responses are seen in experi mental murine infections with Leishmania major. Resistant mice develop a TH1-cell type response and heal the primary lesion, while susceptib le mice develop non-protective Th2-cell responses, and the disease eve ntually proves fatal. Deservedly, much effort has gone into determinin g factors that influence the development of these T-cell subsets early in infection; however, little is known about how the polarity of esta blished responses can be permanently modified. In this article, Gary N abors reviews his findings on modifying ongoing Th2-cell responses in susceptible mice, and discusses therapies that have proven effective i nvolving reducing the level of infection using a conventional antileis hmanial drug, combined with agents that push the response towards the TH1 pole.