In the early phase of leishmaniasis three types of potential antigen-presenting cells, including epidermal Langerhans cells (LC), dermal dendritic cells (DC) and inflammatory DC, are localized at the site of infection. Therefore, it has been a central question which cell type is responsible for the initiation of a protective immune response. In the early stage of an anti-Leishmania immune response, detectable Leishmania major antigen was localized in the paracortex of the draining lymph nodes (LN). Characterization of antigen-positive cells showed that L. major co-localized with DC of a CD11c+ CD8α - Langerin- phenotype. To determine the area of antigen uptake, dermis or epidermis, and to further define the type of antigen -transporting cells, L. major was inoculated subcutaneously and concurrently LC were mobilized with fluorescein isothiocyanate (FITC . After 3 days, DC carrying L. major antigen were always FITC-, indicating a dermal and not an epidermal origin. Moreover, addition of L. major antigen to ex vivo isolated CD8α - and CD8α+ DC from the draining LN of L. major-infected C57BL/6 mice demonstrated that both DC subpopulations were able to stimulate antigen-specific T cell proliferation in vitro. Without addition of exogenous antigen only the CD8α- Langerin- DC were capable of stimulating antigen-specific T cell proliferation. Thus, we demonstrate that CD8α- Langerin DC and not LC are the basis of the protective immune response to intracellular L. major parasites in vivo. © 2004 Wiley-VCH Verlag GmbH & Co. KGaA.

Item Type:	Refereed Article
Research Division:	Biomedical and Clinical Sciences
Research Group:	Immunology
Research Field:	Immunology not elsewhere classified
Objective Division:	Health
Objective Group:	Clinical health
Objective Field:	Clinical health not elsewhere classified
UTAS Author:	Korner, H (Professor Heinrich Korner)
ID Code:	72476
Year Published:	2004
Web of Science® Times Cited:	118
Deposited By:	Research Division
Deposited On:	2011-08-26
Last Modified:	2011-10-04
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