The regulation of T cell responses by a subpopulation of CD8+DEC205+ murine dendritic cells.

Abstract

Dendritic cells (DC) are migratory bone-marrow-derived cells of sparse but broad tissue distribution1,2. They are not homogeneous and even within a particular lymphoid organ distinct subpopulations can be separated3–5. If procedures are used which extract all DC, both CD8α+ and CD8α− DC can be isolated from mouse spleen5. Under these conditions the DC isolated from thymus are predominantly CD8+, whereas those isolated from lymph nodes (LN) are predominantly CD8−. This heterogeneity may be of functional importance, since there is evidence that the CD8+ DC of the thymus are of different developmental origin from the classical CD8− DC typically found in LW6,7. Since conventional isolation procedures yielded mainly the CD8− DC population the functional capacity of CD8+ DC had not previously been explored. To determine whether CD8+ and CD8− splenic DC differed in function, we tested their capacity to stimulate purified allogeneic CD4 and CD8 T cells in a primary mixed leucocyte reaction.