Cell contact-mediated macrophage activation for antileishmanial defense. I. Lymphocyte effector mechanism that is contact dependent and noncytotoxic.
- 30 November 1984
- journal article
- research article
- Published by The American Association of Immunologists in The Journal of Immunology
- Vol. 133 (6), 3358-3365
- https://doi.org/10.4049/jimmunol.133.6.3358
Abstract
Leishmania are obligate intracellular protozoa in mammalian hosts. They infect and replicate within macrophages. Antileishmanial host defense is largely cell mediated. We conducted studies in vitro to investigate the ability of lymphocytes to activate macrophages for antileishmanial effects. Draining lymph node lymphocytes from C57BL/6 mice with cutaneous Leishmania tropica major infection were co-cultured in suspension with syngeneic, starch-elicited peritoneal macrophages infected in vitro with homologous parasites. In the presence of these effector lymphocytes, parasite replication was inhibited, and in some cases intracellular parasites were destroyed. In contrast, control lymphocytes from complete Freund's adjuvant-treated or Listeria-infected mice exerted no antileishmanial effects. Antileishmanial effects were greatest when Leishmania-sensitized lymphocytes were in direct contact with parasitized macrophages. Effector lymphocytes did not cause detectable damage to infected macrophages. Lymphocytes that induced the most profound antileishmanial effects in vitro were those obtained from mice entering a phase of spontaneous clinical resolution of their infections. We conclude that macrophages can be activated for microbicidal effects by direct contact with appropriately sensitized lymphocytes. This antigen-specific, contact-mediated lymphocyte effector mechanism may be important in host defense against certain intracellular microorganisms such as Leishmania.This publication has 3 references indexed in Scilit:
- Cell-mediated immune response in experimental visceral leishmaniasis. I. Correlation between resistance to Leishmania donovani and lymphokine-generating capacity.The Journal of Immunology, 1982
- Cellular immunity of mice to Leishmania donovani in vitro: lymphokine-mediated killing of intracellular parasites in macrophages.Proceedings of the National Academy of Sciences, 1981
- Isolation and Partial Characterization of Surface Membranes From Leishmania Donovani Promastigotes*The Journal of Protozoology, 1980