02080nas a2200289   4500000000100000008004100001260001300042653002400055653002000079653002000099653001100119653002100130653002500151653002600176653001400202653002500216653001800241100001300259700001500272700001100287245011700298856009000415300001000505490000700515520125400522022001401776       1989                            d  c1989 May10aAntigens, Bacterial10aCells, Cultured10aDendritic Cells10aHumans10aInterferon-gamma10aLeprosy, lepromatous10aLymphocyte Activation10aMonocytes10aMycobacterium leprae10aT-Lymphocytes1 aMittal A1 aMishra R S1 aNath I00aAccessory cell heterogeneity in lepromatous leprosy; dendritic cells and not monocytes support T cell responses.  uhttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC1541825/pdf/clinexpimmunol00086-0087.pdf  a233-90 v763 a<p>Dendritic cell (DC)-enriched cell populations from anergic lepromatous leprosy (LL) patients were found to be several-hundred-fold more efficient than monocytes (MO) in promoting antigen-induced T cell responses in autologous accessory + T cell cultures. Whereas, the use of autologous monocytes over a wide concentration range failed to stimulate Mycobacterium leprae-induced T cell proliferation, DC at concentrations as low as 0.1% induced significant proliferation in 9/15 and interferon gamma production in 14/15 LL patients. Four of the LL patients who failed to show proliferation were, however, able to secrete interferon gamma in the same T cell + DC co-cultures. DC were able to present particulate leprae antigens to autologous T cells. This preference for DC as an accessory cell was not shown when the cross-reacting antigen PPD was used in parallel co-cultures. Though tuberculoid leprosy patients showed some improvement in T cell proliferation with DC as compared to MO constituted co-cultures, this was not statistically significant. These results suggest that there is a heterogeneity in accessory cell requirement across the leprosy spectrum and that many lepromatous patients possess M. leprae-reactive functional T cells.</p>  a0009-9104