Prophylactic immunization against experimental leishmaniasis. III. Protection against fatal Leishmania tropica infection induced by irradiated promastigotes involves Lyt-1+2- T cells that do not mediate cutaneous DTH.
- 1 January 1984
- journal article
- research article
- Published by The American Association of Immunologists in The Journal of Immunology
- Vol. 132 (1), 456-461
- https://doi.org/10.4049/jimmunol.132.1.456
Abstract
Protective immunity against fatal L. tropica infection in genetically vulnerable BALB/c mice can be induced by prophylactic immunization with irradiated promastigotes even when heat-killed. Such immunity is adoptively transferable transiently into intact or durably into sub-lethally irradiated (200 or 550 rad) syngeneic recipients by splenic T but not B cells. The effector T cells are of the Lyt-1+2- phenotype, devoid of demonstrable cytotoxic activity. The immune splenic T cell population expresses specific helper activity for antibody synthesis. A causal role for helper T cells in this capacity, however, seems unlikely, because it was shown in the accompanying paper that antibody does not determine the protective immunity against L. tropica. The immunized donors show no detectable cutaneous DTH or its early memory recall in response to live or killed promastigotes or a soluble L. tropica antigen preparation. Spleen, lymph node, and peritoneal exudate cells from protectively immunized donors similarly fail to transfer DTH locally or systemically. These cells also lack demonstrable suppressive activity against the expression or induction of DTH to L. tropica. Thus, protection against L. tropica induced by prophylactic i.v. immunization with irradiated promastigotes appears to be conferred by Lyt-1+2- T cells that are distinguishable from T cells mediating either both DTH and T help, or cytotoxicity.This publication has 3 references indexed in Scilit:
- Is the delayed-type hypersensitivity observed after a low dose of antigen mediated by helper T cells?The Journal of Immunology, 1983
- Single gene control of resistance to cutaneous leishmaniasis in miceImmunogenetics, 1981
- IMMUNOLOGIC UNRESPONSIVENESS IN ADULT GUINEA PIG .I. SUPPRESSION OF DELAYED HYPERSENSITIVITY AND ANTIBODY FORMATION TO PROTEIN ANTIGENS1965