@entity6732 ( @entity6732 ) are sparse muscle-like cells in the thymic medulla, which are believed to trigger the autoimmune response in @entity1737 ( @entity1737 ). Ultrastructural investigations have revealed mature, degenerating, and immature @entity6732 , but the number of @entity6732 in @entity1737 @entity1 does not differ from that in controls. We examined the turnover of @entity6732 at the subcellular level, performing an immunocytochemical study with muscle-specific anti-desmin labelling of 10 thymuses derived from @entity1737 @entity1 with @entity1373 and from 8 normal controls. All thymuses examined revealed mature, immature, and degenerating @entity6732 . Mature @entity6732 contained desmin filaments in between Z-discs provided the sarcomeres were arranged in register. Morphological features of degenerating @entity6732 included hypercontracted sarcomeres, cytoplasmic granular debris, chromatin clumping and, occasionally, membrane-bound bodies. Macrophages were not involved in the process. Immature @entity6732 were of small diameter and contained myofilaments not arranged in myofibrils. In an @entity1737 thymus, small immature @entity6732 were found clustered with dying @entity6732 . It may be that degeneration of @entity6732 is a stimulus for the generation of new @entity6732 with faster turnover. This mechanism may mean that more antigen is available in @entity1737 @entity1 than in normal controls, despite constant @entity6732 numbers.

Thymic myoid cell turnover in @entity1737 XXXX and in normal controls.

@entity1 :: ('9606', 'Species') :: ['patients'] @entity1373 :: ('MESH:D006965', 'Disease') :: ['lymphofollicular hyperplasia'] @entity6732 :: ('MESH:D013953', 'Disease') :: ['Thymic myoid cells', 'TMC'] @entity1737 :: ('MESH:D009157', 'Disease') :: ['MG', 'myasthenia gravis']
@entity1 :: (9606,Species) :: ['patients']
