Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5555467 | International Immunopharmacology | 2017 | 10 Pages |
â¢Procyanidin B2 (PCB2) gallate inhibited proliferation and T cell activation.â¢The production of cytokines was suppressed by treatment with PCB2 gallate.â¢PCB2 gallate significantly inhibited IFN-γ and IL-17 production.â¢PCB2 gallate suppressed the expression of transcription factor T-bet and RORγt.
Procyanidins are widely found in plants and have anti-inflammatory activities. Procyanidin B2 (PCB2) inhibits production of proinflammatory cytokines in macrophages. However, there has been no study that has attempted to determine the effects of PCB2 gallates on T cell functions. In the present study, murine splenocytes were isolated and treated with PCB2 or PCB2 gallates in the presence of an anti-CD3 monoclonal antibody (mAb). PCB2 gallates, but not PCB2, inhibited proliferation and T cell activation of splenocytes after stimulation with the anti-CD3 mAb. In addition, PCB2 gallates, particularly 3,3â³-di-O-gallate (3,3â³-di-OG), significantly inhibited production of interferon (IFN)-γ, interleukin (IL)-12p40, and IL-17 in splenocytes, but did not suppress IL-10 production. Intracellular staining revealed that the expression of IFN-γ and IL-17 in both CD4+ and CD8+ T cells was obviously decreased by PCB2 3,3â³-di-OG compared with PCB2, PCB2 3-OG, and PCB2 3â³-OG. Treatment of isolated CD4+ and CD8+ T cells with procyanidins in the presence of the anti-CD3 mAb led to significant inhibition of IFN-γ production by PCB2 3,3â³-di-OG in both cell types. Furthermore, PCB2 3,3â³-di-OG suppressed the expression of transcription factors T-bet and RORγt that regulate IFN-γ and IL-17, respectively. In conclusion, we revealed a new mechanism through which PCB2 gallates inhibit IFN-γ and IL-17 production in T cells by down-regulation of T-bet and RORγt expression. Our results suggest that PCB2 gallates have a potential role in Th1/Th17-mediated diseases such as inflammatory and autoimmune diseases.
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