Dendritic cells and T lymphocytes: developmental and functional interactions.
Dendritic cells (DCs) are specialized for presentation of antigen to T cells and are essential for primary T cell activation. Although DCs are generally considered to be myeloid derived, we now have evidence that a subgroup are of lymphoid origin. In particular, the DCs of the adult mouse thymus appear to be derived from the same early, lymphoid-restricted precursor cells that generate T lymphocytes. Purified early thymic T precursors have the capacity to produce T cells, B cells, NK cells and DCs, but not myeloid cells, on transfer to irradiated recipients. They also produce thymic DCs on culture with a mix of cytokines; this mix does not include GM-CSF, needed to generate myeloid-derived DCs. A subgroup of DCs in other lymphoid organs, which like thymic DCs express CD8 as an alpha alpha homodimer, may likewise be of lymphoid origin. These CD8+ DCs in mouse spleen differ functionally from the conventional CD8+ DCs. CD8+ DCs efficiently activate CD4+ T cells but then kill them via Fas ligand on the DC surface. CD8+ DCs efficiently recruit CD8+ T cells into the cell cycle, but their proliferation is then restricted by an inadequate production of interleukin 2. This subgroup of CD8+ DCs therefore appears to have a regulatory role.
Shortman
K
K
Walter and Eliza Hall Institute of Medical Research, Royal Melbourne Hospital, Victoria, Australia.
Wu
L
L
Süss
G
G
Kronin
V
V
Winkel
K
K
Saunders
D
D
Vremec
D
D
D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D002454:Cell Differentiation; D003713:Dendritic Cells / Q000276:immunology*; D015332:Gene Rearrangement, alpha-Chain T-Cell Antigen Receptor; D015333:Gene Rearrangement, beta-Chain T-Cell Antigen Receptor; D007111:Immunity, Cellular; D016130:Immunophenotyping; D008213:Lymphocyte Activation; D051379:Mice; D013154:Spleen / Q000166:cytology; D013601:T-Lymphocytes / Q000276:immunology*; D013950:Thymus Gland / Q000166:cytology