The article presents the information on the latest scientific data regarding the pathogenesis and morphofunctional state of the thymus of patients with myasthenia gravis. Myasthenia gravis has been actively studied since 1970, especially after the detection of antibodies against AChR (autoantibodies to acetylcholine receptors). Acquired autoimmune myasthenia gravis should be distinguished from congenital, which has similar clinical manifestations not due to immunopathological dysregulation, but due to genetic mutations. In this study, the term "myasthenia gravis" refers exclusively to acquired autoimmune myasthenia gravis. Although congenital myasthenia gravis is caused by mutations in genes encoding components of the neuromuscular synapse, the genetic contribution to acquired autoimmune myasthenia gravis is less obvious. Several references to families with multiple cases of myasthenia gravis are found in the literature, however, the increased risk of developing myasthenia gravis or other autoimmune diseases among relatives of patients with myasthenia gravis supports the idea of a genetic predisposition that promotes increased susceptibility to myasthenia gravis. Changes in neuromuscular synapse in patients with myasthenia gravis include enlargement of the synaptic cleft, reduction of AChR and flattening of the postsynaptic membrane, the so-called violation of synaptic architecture. These changes develop at the expense of persistent autoimmune attacks on the postsynaptic membrane. Depending on the specific autoantibodies involved in the autoimmune attack, myasthenia gravis can be roughly divided into 3 categories: AChR myasthenia gravis, MuSK myasthenia gravis, and Seronegative myasthenia gravis. Numerous studies have greatly improved our understanding of the etiology, pathogenesis, morphology, and principles of the treatment of myasthenia gravis. Antigenic targets were identified and described, a new classification of myasthenia gravis was developed, and the basics were laid for the study of the chemokine system, which plays an important role in the pathogenesis of myasthenia gravis. However, it is still not clear why thymectomy is relatively effective in patients with thymic lympho-follicular hyperplasia and virtually ineffective in its atrophy or even in its normal state. No clear clinical morphological criteria have been developed to predict the course of the disease and the effectiveness of thymectomy. Conclusion. Despite the fact that myasthenia gravis is a very rare disease, its disabling effect, which dramatically reduces the quality and life expectancy of patients, forces the scientific community to look for different ways to address the etiology, pathogenesis, morphology and treatment of myasthenia gravis.
Keywords: thymus, myasthenia gravis, autoimmune disease
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