Natural and acquired resistance to Leishmania: cellular activation by Leishmania aethiopica of mononuclear cells from unexposed individuals is through the stimulation of natural killer (NK) cells.
Cells from normal non-Leishmania-exposed individuals could respond in vitro by proliferation and interferon-gamma (IFN-gamma) production to Leishmania aethiopica stimulation. The main cell type that appeared to be activated following such stimulation was CD3-, CD16+/56+, i.e. NK cells. Of the few CD3+ cells responding, an involvement of CD8+ cells was evident in the absence of activation of CD4+ cells in normal individuals, while a different feature was observed when patients' cells were investigated. Cells from patients with L. aethiopica infection did not show this NK response, but rather the CD4+ cells were the prominent responding cells. No evidence of the involvement of superantigens or cells utilizing the gamma delta T cell receptor (gamma delta cells) in the response of unexposed individuals was noted.
Akuffo
H
H
Department of Infectious Diseases, Karolinska Institute, Huddinge Hospital, Sweden.
Maasho
K
K
Howe
R
R
D000328:Adult; D000818:Animals; D015703:Antigens, CD / Q000276:immunology; D000953:Antigens, Protozoan / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D016207:Cytokines / Q000096:biosynthesis; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007111:Immunity, Cellular; D007113:Immunity, Innate; D007694:Killer Cells, Natural / Q000276:immunology*; D007891:Leishmania / Q000276:immunology*; D007896:Leishmaniasis / Q000276:immunology*; D007963:Leukocytes, Mononuclear / Q000276:immunology; D008213:Lymphocyte Activation / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000276:immunology
D015703:Antigens, CD; D000953:Antigens, Protozoan; D016207:Cytokines; D016693:Receptors, Antigen, T-Cell, alpha-beta