In Vivo T Cell Activation Induces the Formation of CD209+ PDL-2+ Dendritic Cells: e76258

• Published in: PloS one 2013-10, Vol.8 (10)
• Main Authors: Davidson, Matthew G, Alonso, Michael N, Kenkel, Justin A, Suhoski, Megan M, Gonzalez, Joseph C, Yuan, Robert, Engleman, Edgar G
• Format: Article
• Language: English
• ISSN: 1932-6203
• DOI: 10.1371/journal.pone.0076258

Two critical functions of dendritic cells (DC) are to activate and functionally polarize T cells. Activated T cells can, in turn, influence DC maturation, although their effect on de novo DC development is poorly understood. Here we report that activation of T cells in mice, with either an anti-CD3 antibody or super antigen, drives the rapid formation of CD209+CD11b+CD11c+ MHC II+ DC from monocytic precursors (Mo-DC). GM-CSF is produced by T cells following activation, but surprisingly, it is not required for the formation of CD209+ Mo-DC. CD40L, however, is critical for the full induction of Mo-DC following T cell activation. T cell induced CD209+ Mo-DC are comparable to conventional CD209- DC in their ability to stimulate T cell proliferation. However, in contrast to conventional CD209- DC, CD209+ Mo-DC fail to effectively polarize T cells, as indicated by a paucity of T cell cytokine production. The inability of CD209+ Mo-DC to polarize T cells is partly explained by increased expression of PDL-2, since blockade of this molecule restores some polarizing capacity to the Mo-DC. These findings expand the range of signals capable of driving Mo-DC differentiation in vivo beyond exogenous microbial factors to include endogenous factors produced following T cell activation.