Myasthenia gravis (MG) and its animal model EAMG are caused by autoantibodies against nicotinic acetylcholine receptors (AChR) at the neuromuscular junction [2]

Myasthenia gravis (MG) and its animal model EAMG are caused by autoantibodies against nicotinic acetylcholine receptors (AChR) at the neuromuscular junction [2]. degradation. Numbers of AChR-reactive IFN- and tumour necrosis factor-alpha (TNF-) mRNA-expressing lymph node cells from rats treated nasally with 600 g/rat of AChR were suppressed, while IL-4, IL-10 and transforming growth factor-beta (TGF-) mRNA-expressing cells were not affected. Collectively, these data indicate that nasal administration of AChR in ongoing EAMG induced selective suppression of Th1 functions, i.e. IFN- and IgG2b production, but no influence on Th2 cell functions. The impaired Th1 functions may result in the production of less myasthenic anti-AChR antibodies and contribute to the Nidufexor amelioration of EAMG severity in rats treated with AChR 600 g/rat by the nasal route. Keywords: mucosal tolerance, experimental autoimmune myasthenia gravis, Th1 cells, Th2 cells, cytokine INTRODUCTION Mucosal antigen exposure without adjuvant results in immunological unresponsiveness upon subsequent parenteral challenge, i.e. mucosal tolerance. Oral tolerance induction involves multiple mechanisms, including the induction of apoptosis and anergy of antigen-specific T cells following administration of high antigen doses, while induction of regulatory Th2 and Th3 cells follows low-dose antigen feeding (reviewed in [1]). Exploitation of the oral route for prevention and treatment of autoimmune disease has dealt with experimental models of cell-mediated conditions, such as experimental autoimmune encephalomyelitis (EAE), uveitis (EAU), or arthritis. Myasthenia gravis (MG) and its animal model EAMG are caused by autoantibodies against nicotinic acetylcholine receptors (AChR) at the neuromuscular junction [2]. The production of anti-AChR antibodies is mediated by cytokines produced by T helper (Th) [3,4]. Immunotherapies aimed at targeting disease-inducing AChR-specific Th cell populations should be effective in EAMG. We and others have used oral tolerance induction as a strategy to prevent EAMG, and found that oral administration of AChR inhibits clinical EAMG and suppresses both humoral and cellular immune responses [5C7]. AChR administration by the nasal route, although only 1/1000 of the dose of AChR needed, is definitely still as effective as oral tolerance induction [8]. Nidufexor To determine whether nose administration of AChR can be used to treat ongoing EAMG, i.e. a situation more likely to be encountered in human being MG, we given AChR nasally to Nidufexor Lewis rats 2 weeks after immunization with AChR + Freund’s total adjuvant (FCA). The effects of nose administration of AChR in ongoing EAMG were evaluated Rabbit Polyclonal to AKAP8 following several important elements: (i) medical course of EAMG; (ii) AChR-induced T cell reactions; (iii) anti-AChR antibody specificity; (iv) cytokine profiles. MATERIALS AND METHODS Antigen preparations AChR Nidufexor was purified from your electroplax cells of (Pacific Biomarine, Venice, CA) by affinity chromatography on -cobrotoxin-agarose resin (Sigma, St Louis, MO) [9]. The product was genuine as judged by SDSCPAGE. The control antigen myelin fundamental protein (MBP) was purified from guinea pig spinal cord [10]. Purity was confirmed by SDSCPAGE. Immunization Female Lewis rats, 8 weeks of age, were purchased from Charles River Co. (Sulzfeld, Germany). Each rat was immunized subcutaneously in both hind footpads and foundation of tail with 50 g of AChR emulsified in FCA in a total volume of 200 l. The medical severity of EAMG was blindly graded [11] as follows: 0, no weakness; 1 +, mildly decreased activity, weak grip or cry, with fatigue; 2 +, markedly decreased activity and body weight, hunched posture at rest, head down and forelimb digits flexed, tremulous ambulation; and 3 +, severe generalized weakness, no cry or grip. Rats were killed at day time 49 post-immunization (p.i.). Nasal tolerance induction The routine previously explained for rats nasally tolerized with AChR before immunization [8] was revised. Two.