Human peripheral blood-derived dendritic cells do not produce interleukin 1 alpha, interleukin 1 beta, or interleukin 6.
Little is known about the non-antigen-specific signals delivered to T cells by dendritic cells (DC). Because several monocyte-derived factors like interleukins 1 alpha, 1 beta, and 6 (IL-1 alpha, IL-1 beta, and IL-6) enhance the T-cell proliferative responses, we studied the production of the above-mentioned cytokines by DC separated from human peripheral blood. The intracellular expression of the proteins (IL-1 alpha and IL-6) was studied at a single-cell level using an immunolabelling technique. The supernatants and cell lysates were studied with ELISA (IL-1 alpha and IL-1 beta). Northern blotting analysis was used to quantitate the mRNA levels. Several approaches were taken to stimulate the production of IL-1 alpha, IL-1 beta, and IL-6 by DC. These included the incubation of the DC in the presence of either LPS, rIL-1, or monoclonal anti-HLA-DR antibody, or the stimulation of cells with resting allogeneic T cells. None of the stimuli was able to induce the production of IL-1 alpha, IL-1 beta, or IL-6 by DC, whereas LPS-stimulated monocytes were strong producers of these mentioned cytokines and expressed the respective mRNA. Thus we concluded that IL-1 alpha, IL-1 beta, and IL-6 are primarily monocyte-derived factors and that these factors are not needed or produced during the activation of resting T cells by DC.
Vakkila
J
J
Department of Bacteriology and Immunology, University of Helsinki, Finland.
Sihvola
M
M
Hurme
M
M
D000818:Animals; D002478:Cells, Cultured; D003713:Dendritic Cells / Q000378:metabolism*; D006801:Humans; D007375:Interleukin-1 / Q000096:biosynthesis* / Q000235:genetics; D015850:Interleukin-6 / Q000096:biosynthesis* / Q000235:genetics; D008070:Lipopolysaccharides / Q000494:pharmacology; D009000:Monocytes / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis; D011817:Rabbits
D007375:Interleukin-1; D015850:Interleukin-6; D008070:Lipopolysaccharides; D012333:RNA, Messenger