These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Tgf-beta inhibits activation and uveitogenicity of primary but not of fully polarized retinal antigen-specific memory-effector T cells.
    Author: Xu H, Silver PB, Tarrant TK, Chan CC, Caspi RR.
    Journal: Invest Ophthalmol Vis Sci; 2003 Nov; 44(11):4805-12. PubMed ID: 14578402.
    Abstract:
    PURPOSE: TGF-beta exerts suppressive effects on immunity, but its potential applications in therapy of ocular autoimmunity have not been widely explored. In the present study, the effects of TGF-beta on uveitogenic T cells were examined. METHODS: The effects of TGF-beta on newly primed cells from mice given a uveitogenic regimen of interphotoreceptor retinoid-binding protein (IRBP) were compared with the effects on fully polarized Th1 cells from a long-term uveitogenic T-cell line. The parameters measured were T-cell proliferation, IFN-gamma production, induction of IL-12R expression, triggering of pathogenicity, and expression of costimulatory molecules on antigen-presenting cells (APCs) during in vitro exposure to antigen. RESULTS: TGF-beta suppressed B7.1 expression on APCs in cultures of lymph node cells from immunized mice. It also suppressed T-cell proliferation, IFN-gamma production, IL-12 receptor accumulation, and the IL-12-promoted acquisition of uveitogenic function. In contrast, the polarized Th1 cells were either resistant to suppression or were enhanced by TGF-beta. CONCLUSIONS: The results suggest that TGF-beta suppresses acquisition of effector functions by autopathogenic T cells, in part by interfering with their response to IL-12 through downregulation of IL-12R expression and in part through inhibition of APC function. The data suggest that although TGF-beta may effectively inhibit activation and recruitment of new T cells into the effector pool, it may be less effective in suppressing the reactivation of already polarized memory T cells that are less dependent on IL-12 and costimulation.
    [Abstract] [Full Text] [Related] [New Search]