Arthritis & Rheumatism, Volume 62,
November 2010 Abstract Supplement
Abstracts of the American College of
Rheumatology/Association of Rheumatology Health Professionals
Annual Scientific Meeting
Atlanta, Georgia November 6-11, 2010.
Vitamin D Suppresses Th17 Cytokines Via Down Regulation of RORgammat and NFATC2 and by Differential Regulation of GATA3.
Mus2, Anne-Marie, van Hamburg2, Jan Piet, Asmawidjaja2, Patrick, Hazes2, Johanna M. W., van Leeuwen2, Hans, Boon1, Louis, Colin2, Edgar
Recently, we showed that vitamin D modulated Th17 polarization and IL-22 expression by memory T cells from patients with early rheumatoid arthritis and stimulates IL-4 production by PBMC from early RA patients. Furthermore, it has been shown that vitamin D inhibited collagen-induced arthritis and diminished the severity of existing CIA, although the mechanism is unknown.
To identify the molecular mechanism of vitamin D on suppression of Th17 cytokines and Th17 differentiation in an ex vivo model using CD4+ T cells from the prone autoimmune DBA-1 mice with and without collagen-induced arthritis or naïve CD4+ cells from DBA-1 mice.
Splenic CD4+ T cells of non-immunized DBA-1 and type II collagen immunized DBA-1 mice were isolated using the MACS system. In addition, naïve splenic CD4+CD62L+ T cells were FACS sorted from DBA-1 mice. These cells were stimulated in vitro under either Th0, Th1 (IL-12/anti-IL-4) or Th17 (IL-23, TGF-b, IL-6, anti-IL-4 and anti-IFN-g) conditions with or without the presence vitamin D. Intracellular flowcytometric stainings for the detection of cytokine and transcription factor expression were performed. In addition, cytokine expression in supernatant was detected by specific ELISA. Moreover, mRNA expression of factors involved in Th differentiation and function was analyzed by Q-PCR.
Higher percentages of IL-17+IFN-g- (Th17) cells were obtained after Th17 polarizing cultures of splenic CD4+ T cells of CII-immunized mice, compared to non-immunized mice DBA-1. In cultures of both non-immunized mice and CII-immunized DBA-1 mice, Vitamin D significantly inhibited Th17 polarization, as indicated by reduced IL-17A and IL-17F cytokine expression. Moreover, reduced RORgt expression and enhanced GATA3 expression was noted. Interestingly, vitamin D showed an increase in IL-4 and IL-10 positive cells under Th17 polarizing conditions of both non-immunized and CII-immunized DBA-1 mice. However, using FACS sorted naïve CD4+ T cells, vitamin D enhanced IL-4 and GATA3 under Th0 conditions, but not under Th17 polarizing conditions. Interestingly, in this latter condition, RORgt and NFATC2 were markedly suppressed. No effect of vitamin D on T bet and RUNX1 expression was noted.
These data show that vitamin D is a strong inhibitor of Th17 polarization and Th17 cytokine expression of splenic CD4+ T cells from non-immunized and CII-immunized DBA-1 mice. Furthermore, Th17 differentiation from naïve T cells was affected by Vitamin D. These data implicate a regulatory mechanism on Th17 cells by Vitamin D, through the reduction of RORgt expression. This regulatory function of Vitamin D in memory Th17 cells, may in part be dependent on the induction of GATA3 expression leading to a induced Th2 cytokine expression profile.
To cite this abstract, please use the following information:
Mus, Anne-Marie, van Hamburg, Jan Piet, Asmawidjaja, Patrick, Hazes, Johanna M. W., van Leeuwen, Hans, Boon, Louis, et al; Vitamin D Suppresses Th17 Cytokines Via Down Regulation of RORgammat and NFATC2 and by Differential Regulation of GATA3. [abstract]. Arthritis Rheum 2010;62 Suppl 10 :38