[Distribution of B-lymphocyte subgroup CD20 and its clinical significance in patients with myasthenia gravis].

OBJECTIVE

To assess the distribution and clinical significance of B-lymphocyte subgroup CD20 in patients with myasthenia gravis.

METHOD: B-lymphocyte subset CD20 was studied in patients with thymomas associated with or without myasthenia gravis using immunohistochemistry technique.

RESULT: The moderate and obvious aggregation of CD20 positive cells was found in patients with myasthenia gravis, there was a significant difference when compared with those patients without myasthenia gravis (chi(2) = 26.032, P < 0.01). There was negative correlation between the distribution of CD20 positive cells and the staging of thymomas (gamma = 0.07), and no correlation between the distribution and clinical type of myasthenia gravis (gamma < 0.4).

CONCLUSION

The results of this study indicated that pathological changes of thymus are more important than those of thymomas itself in the pathogenesis of myasthenia gravis. The degree of B-lymphocyte subgroup aggregation can not truly reflect clinical status because of the heterogeneity of antibody against acetylcholine receptor.