Author(s): Wei WANG | Dong-ning WEI
Journal: Medical Journal of Chinese People's Liberation Army
ISSN 0577-7402
Volume: 38;
Issue: 7;
Start page: 606;
Date: 2013;
Original page
Keywords: myasthenia gravis | thymoma | thymus gland | allergy and immunology
ABSTRACT
Myasthenia gravis is an acquired autoimmune disorder which is cellular-immunity-dependent, humoral-immunity¬mediated and complement participated. It is still not clear which initial factor causes the immune response. The characteristic of myasthenia gravis is that many of the patients have an abnormality in their thymus. So it is speculated that the immune response is initiated in thymus. The thymus is the central organ of the immune system, playing the key role in T cell generation, diversification and maturation. T cells are positively selected for their recognition of antigens associated with MHC expressed in the thymus, and negatively selected according to their response to the self-antigens. The result of these selection is that the T cell use the MHC expressed on the other cells of the body for recognition of foreign antigens but do not react with self-antigens. Perhaps the most important role of thymus is the induction of immune self-tolerance that functions to prevent self-harm or autoimmunity. Thymomas are functional tumors originated from epithelial of the thymus, which have the capacity to induce T cell to differentiate and mature. What mechanism is Myasthenia gravis associated thymoma initiated by? This review will summarize the existing evidence of thymus, thymoma and myasthenia gravis and try to clarify the immune mechanism of initiation of myasthenia gravis associated thymomas.
Journal: Medical Journal of Chinese People's Liberation Army
ISSN 0577-7402
Volume: 38;
Issue: 7;
Start page: 606;
Date: 2013;
Original page
Keywords: myasthenia gravis | thymoma | thymus gland | allergy and immunology
ABSTRACT
Myasthenia gravis is an acquired autoimmune disorder which is cellular-immunity-dependent, humoral-immunity¬mediated and complement participated. It is still not clear which initial factor causes the immune response. The characteristic of myasthenia gravis is that many of the patients have an abnormality in their thymus. So it is speculated that the immune response is initiated in thymus. The thymus is the central organ of the immune system, playing the key role in T cell generation, diversification and maturation. T cells are positively selected for their recognition of antigens associated with MHC expressed in the thymus, and negatively selected according to their response to the self-antigens. The result of these selection is that the T cell use the MHC expressed on the other cells of the body for recognition of foreign antigens but do not react with self-antigens. Perhaps the most important role of thymus is the induction of immune self-tolerance that functions to prevent self-harm or autoimmunity. Thymomas are functional tumors originated from epithelial of the thymus, which have the capacity to induce T cell to differentiate and mature. What mechanism is Myasthenia gravis associated thymoma initiated by? This review will summarize the existing evidence of thymus, thymoma and myasthenia gravis and try to clarify the immune mechanism of initiation of myasthenia gravis associated thymomas.
