The p.V14M substitution in interferon gamma receptor 1 may affect the signal peptide function and the translocation on cell membrane, which could disrupt the binding of the ligand of interferon gamma and antibody production, contributing to myasthenia gravis susceptibility.
We summarize the preclinical models used to determine the implication of expression of cytokines, such as IL-6, IL-12 (IL-23 subunit), IL-17, and interferon γ to the development of experimental autoimmune MG.
The expression of serum-related cytokines as well as the Treg cell ratio were examined so as to define the contributory role of CTLA-4 methylation in MG and to identify the interaction between CTLA-4 methylation and related factors, the expressions of DNA methyltransferase (DNMT)l, DNMT3A and DNMT3B, CTLA-4, AchR-Ab, Titin-Ab, RyR-Ab, IL-2, IL-10, IFN-γ, and TGF-β, activity of P- acetylcholinesterase (AchE) and E-AchE.
Several GO terms including the cellular response to interferon-γ, platelet degranulation, chemokine receptor binding and cytokine interactions were very important in MG pathogenesis.
Immunosuppression treatment had two effects: First, it reduced levels of IL12p40 in the plasma of AChR-MG and MuSK-MG patients, leaving other cytokine levels unchanged; second, it reduced spontaneous secretion of IFN-γ and increased secretion of IL-6 and IL-10 by cultured PBMC from AChR-MG, but not MuSK-MG patients.
The findings imply that IFN-gamma and STAT-1 signaling play a role in MHCII expression in the human thymus and in the pathogenesis of paraneoplastic MG.
IFNG +874T carriers were less frequent in MG, in patients with anti-acetylcholine receptor (AChR) (63%) and anti-titin (56.2%) antibodies compared with HC (p = 0.01 for all, OR: 0.5, 0.5, and 0.4, respectively).
Mononuclear cells from paired blood samples from fifteen patients with myasthenia gravis before and after thymectomy and immunosuppressive therapy were examined by in situ hybridization for acetylcholine receptor-induced mRNA expression of the T helper type 1 proinflammatory cytokines interferon gamma (IFN-gamma), tumor necrosis factor alpha (TNF-alpha) and TNF-beta, the T helper type 2 cytokines interleukin 4 (IL-4) and IL-10 and the immune response downregulating cytokine tumor growth factor beta (TGF-beta).
The levels of IFN-gamma and IL-4 mRNA-positive cells in MS after culture in the presence of AChR, and in MG after culture in the presence of MBP or PLP, did not differ from those detected after culture without antigen.
MG patients had elevated numbers of cells expressing IFN-gamma and IL-4 compared to patients with non-inflammatory neurological diseases and healthy controls, implying that both Th1- and Th2-like cells are involved in MG. TGF-beta-positive cells were also elevated in MG.