Cell-surface expression of lymphocyte activation markers in myasthenia gravis

An analysis of the cell-surface expression of activation markers on B- and T-cells was done to compare patients with myasthenia gravis (MG) and health y non-myasthenic controls. Marker expression,vas determined by immunostaini ng of peripheral blood mononuclear cells (PBMC) isolated from MG patients a nd from controls, The percentage of B-cells in PBMC that expressed CD71, a transferrin receptor, was significantly greater in patients compared to con trols, particularly, in patients who were seropositive for acetylcholine re ceptor-specific antibodies, When subgroups of MG patients were studied, our data showed that within the first year after disease onset, patients had a significantly higher percentage of T-cells in PBMC that were CD25(+) (inte rleukin-2 receptor alpha) and CD26(+) (dipeptidyl peptidase IV ectoenzyme) in comparison to patients with disease symptoms for longer than one year an d to healthy controls. Our data also showed that patients with generalized MG had significantly lower percentages of gamma/delta T-cells in peripheral blood compared to healthy controls, The results of this study demonstrate important differences in the cell-surface expression of lymphocyte markers between MG patients and healthy non-myasthenic controls, In addition, diffe rences between subgroups of patients demonstrate that patients with MG are heterogeneous in clinical presentation and in immunological parameters.