Dendritic cells pulsed with protein antigens in vitro can prime antigen-specific, MHC-restricted T cells in situ.
T cells recognize peptides that are bound to MHC molecules on the surface of different types of antigen-presenting cells (APC). Antigen presentation most often is studied using T cells that have undergone priming in situ, or cell lines that have been chronically stimulated in vitro. The use of primed cells provides sufficient numbers of antigen-reactive lymphocytes for experimental study. A more complete understanding of immunogenicity, however, requires that one develop systems for studying the onset of a T cell response from unprimed lymphocytes, especially in situ. Here it is shown that mouse T cells can be reliably primed in situ using dendritic cells as APC. The dendritic cells were isolated from spleen, pulsed with protein antigens, and then administered to naive mice. Antigen-responsive T cells developed in the draining lymphoid tissue, and these T cells only recognized protein when presented on cells bearing the same MHC products as the original priming dendritic cells. In contrast, little or no priming was seen if antigen-pulsed spleen cells or peritoneal cells were injected. Since very small amounts of the foreign protein were visualized within endocytic vacuoles of antigen-pulsed dendritic cells, it is suggested that dendritic cells have a small but relevant vacuolar system for presenting antigens over a several day period in situ.
Inaba
K
K
Rockefeller University, Irvington Institute, New York, New York 10021.
Metlay
J P
JP
Crowley
M T
MT
Steinman
R M
RM
D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology*; D000941:Antigens / Q000276:immunology*; D002478:Cells, Cultured; D003207:Conalbumin / Q000276:immunology* / Q000378:metabolism; D004261:DNA Replication; D003713:Dendritic Cells / Q000276:immunology*; D004527:Egg Proteins / Q000276:immunology*; D004705:Endocytosis; D005260:Female; D007700:Kinetics; D008198:Lymph Nodes / Q000276:immunology; D008213:Lymphocyte Activation; D008285:Major Histocompatibility Complex; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D009211:Myoglobin / Q000276:immunology* / Q000378:metabolism; D010873:Pinocytosis; D013601:T-Lymphocytes / Q000276:immunology*
D000941:Antigens; D004527:Egg Proteins; D009211:Myoglobin; D003207:Conalbumin