Interferon-gamma production by human T cells and natural killer cells in vitro in response to antigens from the two intracellular pathogens Mycobacterium tuberculosis and Leishmania major
Kemp, K.; Hviid, L.; Kharazmi, A.; Kemp, M.
Scandinavian Journal of Immunology 46(5): 495-499
1997
ISSN/ISBN: 0300-9475 PMID: 9393632 Document Number: 483753
Acquired resistance to both mycobacteria and Leishmania is primarily mediated by interferon-gamma (IFN-gamma), which triggers mechanisms leading to the death of the microorganism in macrophages. In this study, cell activation and IFN-gamma production was investigated in human peripheral blood mononuclear cells (PBMC) from individuals previously sensitized to tuberculin and without known exposure to Leishmania parasites. Immune staining for intracellular IFN-gamma and surface markers allowed flow cytometric identification of the cellular sources of IFN-gamma in cell cultures incubated with purified protein derivative of tuberculin (PPD) and Leishmania antigens. It was found that IFN-gamma was produced in response to both PPD and Leishmania stimulant by T cells in the cultures. Activation of IFN-gamma producing natural killer (NK) cells was demonstrated only in some cultures, and only with concomitant T cell activation.