Lymph node fibroblastic reticular cells directly present peripheral tissue antigen under steady-state and inflammatory conditions.

Department of Cancer Immunology and AIDS, Dana-Farber Cancer Institute, Boston, MA 02115, USA.
Journal of Experimental Medicine (Impact Factor: 13.21). 03/2010; 207(4):689-97. DOI: 10.1084/jem.20092642
Source: PubMed

ABSTRACT Lymph node stromal cells (LNSCs) can induce potent, antigen-specific T cell tolerance under steady-state conditions. Although expression of various peripheral tissue-restricted antigens (PTAs) and presentation to naive CD8+ T cells has been demonstrated, the stromal subsets responsible have not been identified. We report that fibroblastic reticular cells (FRCs), which reside in the T cell zone of the LN, ectopically express and directly present a model PTA to naive T cells, inducing their proliferation. However, we found that no single LNSC subset was responsible for PTA expression; rather, each subset had its own characteristic antigen display. Studies to date have concentrated on PTA presentation under steady-state conditions; however, because LNs are frequently inflammatory sites, we assessed whether inflammation altered stromal cell-T cell interactions. Strikingly, FRCs showed reduced stimulation of T cells after Toll-like receptor 3 ligation. We also characterize an LNSC subset expressing the highest levels of autoimmune regulator, which responds potently to bystander inflammation by up-regulating PTA expression. Collectively, these data show that diverse stromal cell types have evolved to constitutively express PTAs, and that exposure to viral products alters the interaction between T cells and LNSCs.

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