TNF controls the infiltration of dendritic cells into the site of Leishmania major infection.
TNF-negative C57BL/6 (B6.TNF(-/-)) mice are highly susceptible to Leishmania (L.) major infection and succumb rapidly to fatal leishmaniasis. A T helper type 1 (Th1) cell-mediated immune response is central for protective anti-leishmanial immunity. Therefore, the observed susceptibility of B6.TNF(-/-) mice to L. major parasites could be caused by a deficiency in mounting a Th1 response. Analysis of infected footpads revealed, that B6.TNF(-/-) mice exhibited a substantially diminished formation of DCs at the site of infection. Furthermore, Th1 cytokines such as IFN-gamma were reduced in footpads of infected B6.TNF(-/-) mice. Cutaneous reconstitution of B6.TNF(-/-) mice with either bone marrow derived DCs (BM-DCs) or recombinant TNF simultaneous to infection resulted in an increased expression of cytokines such as IFN-gamma and in an enhanced presence of Leishmania-antigen in skin draining lymph nodes. In addition, the individual time of survival was doubled. In conclusion we demonstrate that the expression of dermal TNF is necessary to provide an environment that initiates a local inflammatory response, but is not sufficient to induce protective immunity.
Nachwuchsgruppe 1 des Interdisziplinären Zentrums für Klinische Forschung der Universität Erlangen-Nürnberg, Erlangen, Germany. uwe.ritter@klinik.uni-regensburg.de
Uwe
U
Ritter
Anja
A
Lechner
Katja
K
Scharl
Ziba
Z
Kiafard
Jörg
J
Zwirner
Heinrich
H
Körner
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D039521:CD11c Antigen / Q000032:analysis; D002465:Cell Movement / Q000276:immunology; D054421:Chemokine CCL21 / Q000276:immunology; D003713:Dendritic Cells / Q000276:immunology*; D005434:Flow Cytometry; D005528:Foot; D007111:Immunity, Cellular; D007249:Inflammation / Q000276:immunology; D007371:Interferon-gamma / Q000276:immunology; D018320:Leishmania major / Q000276:immunology*; D016773:Leishmaniasis, Cutaneous / Q000276:immunology*; D017493:Leukocyte Common Antigens / Q000032:analysis; D007962:Leukocytes / Q000276:immunology; D008198:Lymph Nodes / Q000166:cytology / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D008856:Microscopy, Fluorescence; D012867:Skin / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology*
D000911:Antibodies, Monoclonal; D039521:CD11c Antigen; D054421:Chemokine CCL21; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma; D017493:Leukocyte Common Antigens