T cell clones for antigen selection and lymphokine production in murine Schistosomiasis mansoni
Reynolds, S.R.; Kunkel, S.L.; Thomas, D.W.; Higashi, G.I.
Journal of Immunology 144(7): 2757-2762
1990
ISSN/ISBN: 0022-1767 PMID: 1690777 Document Number: 359505
The role of T cells in immunity to murine schistosomiasis was examined through the use of T cell clones that recognize the live schistosomulum stage of Schistosoma mansoni. T cells clones of three different phenotypes were isolated and expanded into long term culture from lymph nodes of C57B1/6J mice vaccinated with irradiated S. mansoni larvae. They were characterized by surface markers, lymphokine production, and functional assays. The m.w. range of the Ag recognized by one clone was idenified through nitrocellulose blotting and confirmed with a preparation of the putative protein made by immunoaffinity purification. All but one of the clones were CD4+, CD5+, Th cells. One clone, 35, produced Il-2 and IFN-.gamma. and was designated a TH1 clone. The others were designated TH2 clones bacuse of Il-4 production. One clone was CD8+ and failed to show help. CLone 35 recognized live schistosomula and produced Il-2 when presented a 27-kDa protein fron nitrocellulose. It proliferated in response to purified Ag. Clone 35 participated along with macrophages to induce up to 98% killing of live schistosomula in vitro. IFN-.gamma. and TNF-.alpha. were essential to the killing mechanism whereas Il-1, IL-2, and Il-4 were not required. This study has approached Ag identification for vaccine development from the point of view of T cells and showed that TH1 cells are essential to in vitro macrophage killing of schistosomula in murine schistosomiasis.