Therapeutic effect of ergotope peptides on CIA by down-regulation of inflammatory and Th1/Th17 responses and induction of regulatory T cells.

Rheumatoid arthritis (RA) is a systemic autoimmune disease that results in a chronic and inflammatory disorder. Dynamic balance of helper T cells (Th)1, Th17 and regulatory T cells (Treg) is broken in RA. Since there is no cure for RA at present, it's necessary to find a truly effective and convenient treatment. Several studies intended to induce ergotopic regulation to treat autoimmune diseases. This study was undertaken to find the potential ergotope peptides and investigate its effect in treating the animal model of RA and their underlying regulatory mechanisms. Firstly, we selected the functional ergotope peptides from 25 overlapping peptides derived from interlukin(IL)-2 receptor (IL-2R) α chain, and then used these peptides to treat collagen-induced arthritis (CIA). The study showed ergotope peptides as immunomodulatory factors with great benefits at the clinical and pathologic levels. This effect was associated with the inhibition of type II collagen (CII)-specific proliferation and autoantibody production as well as the induction of anti-ergotypic immune response, the down-regulation of both Th1 and Th17 cells and their related components, and the emergence of Treg cells that had suppressive actions on autoreactive T cells. We also proved that cytotoxic T lymphocyte associated antigen-4 (CTLA-4) and IL-10 are two important mediators which are critical to Treg suppressive function. The inhibition of Th1 and Th17 in established CIA could be attributed to ergotope induced Treg cells. Our findings reveal that ergotope peptides induce regulatory immune responses and restore immune tolerance, suggesting ergotope peptides treatment appears to be a novel approach to the therapy of RA patients and has a good application prospect with cheap, effective, convenient, wide-spectrum features.

T cell vaccination inhibits Th1/Th17/Tfh frequencies and production of autoantibodies in collagen-induced arthritis.

The aim of this study is to determine whether the regulatory role of T cell vaccination (TCV) is through inhibition of Th1/Th17/Tfh and production of autoantibodies on collagen-induced arthritis (CIA). First, CIA mice were treated with TCV. After disease onset, the incidence and severity of change in joint histopathology were evaluated. Mice in the TCV-treated group showed less disease severity and less infiltration of inflammatory cells in the joint sections. TCV decreased the frequencies of Th1/Th17/Tfh cells and related cytokines. Reduction of IL-21 may be associated with both Tfh and Th17, which further influence B cell and T cell responses. In addition, inhibition of Th1/Th17/Tfh frequencies led to the reduced expression of T-bet, ROR α , ROR γ t, and Bcl6. Lastly, the proliferation of type-II-collagen-(CII-) specific T cells and the production of anti-CII antibodies were inhibited in the TCV-treated group. The results provide novel evidence that the therapeutic effects of TCV on CIA are associated with the inhibition of Th1/Th17/Tfh frequencies and autoantibodies production.

IFN-ß induces the proliferation of CD4+CD25+Foxp3+ regulatory T cells through upregulation of GITRL on dendritic cells in the treatment of multiple sclerosis.

IFN-ß is a major disease-modifying agent used for the treatment of multiple sclerosis (MS). Its mechanisms are complex and it has broad immunomodulatory effects on many types of immune cells. It was observed clinically that the quantity of CD4(+)CD25(+)Foxp3(+) regulatory T cells increases in some MS patients treated with IFN-ß. In this study, we show that IFNAR engagement by IFN-ß expands naturally occurring CD4(+)CD25(+)Foxp3(+) regulatory T cell population through the modulation of dendritic cells (DCs). IFN-ß has no effect on the conversion of CD4(+)CD25(-) T cells to adaptive Treg cells. The IFN-ß-induced upregulation of GITRL on DC and downregulation of CTLA-4 on Treg cell work together to facilitate the proliferation of anergic Treg cells. In MS patients treated with Avonex or Rebif (IFN-ß), it was found that GITRL expression is markedly upregulated on peripheral CD14(+) cells. Our findings help the better understanding of the complex effects of IFN-ß in the treatment of MS.

Regulatory immune responses induced by IL-1 receptor antagonist in rheumatoid arthritis.

Anakinra, a human recombinant IL-1 receptor antagonist, is approved for the treatment of RA. In this study, 12 patients received the placebo plus MTX treatment, 38 patients received Anakinra combined with MTX treatment. Compared with the placebo plus MTX group, serum levels of IL-17, IFN-γ, IL-21 and IL-1ß significantly decreased, the percentages of Th17 cells and Th1 cells were lower and the percentage of Treg cells was higher after receiving Anakinra combined with MTX treatment. The observed regulatory immune responses collectively correlated with clinical improvement in treated patients. A substantial response, ACR 20 at 24 w were consistent with those at 12 w, 16 w and 20 w, and was accompanied by a marked improvement in RA related laboratory parameters. The study reveals that the combination of Anakinra and MTX is safe and well tolerated, which induces regulatory immune responses and significantly provides greater clinical benefit than the placebo plus MTX group.

Biphenyl-3,3'-dicarb-oxy-lic acid.

The asymmetric unit of the title compound, C(14)H(10)O(4), contains one half mol-ecule, the complete mol-ecule being generated by a twofold axis. The two benzene rings form a dihedral angle of 43.11 (5)°. Inter-molecular O-H⋯O hydrogen bonds link the mol-ecules into one-dimensional zigzag chains. These chains are further connected into two-dimensional supra-molecular layers by weak π-π stacking inter-actions between neighbouring benzene rings, with centroid-centroid distances of 3.7648 (8) Å.

Regulatory effect of vasoactive intestinal peptide on the balance of Treg and Th17 in collagen-induced arthritis.

Vasoactive intestinal peptide (VIP) is a well-known anti-inflammatory neuropeptide. The capacity of VIP can be exhibited through inhibiting inflammatory responses, shifting the Th1/Th2 balance in favor of anti-inflammatory Th2 immunity and inducing regulatory T cells (Tregs) with suppressive activity. In addition to pro-inflammatory Th1 response, Th17 are also believed to play important roles in the pathogenesis of rheumatoid arthritis (RA). In this study, we used collagen-induced arthritis (CIA) model in Wistar rats to investigate the role of VIP in the balance of CD4(+) CD25(+) Tregs and Th17 on RA. Data presented here showed that administration of VIP decreased incidence and severity of CIA. Disease suppression was associated with the upregulation of CD4(+) CD25(+) Tregs, downregulation of Th17- and Th1-type response and influence on the RANK/RANKL/OPG system. The results provide novel evidence that the therapeutic effects of VIP on CIA rats were associated with the balance of CD4(+) CD25(+) Tregs and Th17.