Cellular immune response against acetylcholine receptor in myasthenia gravis: I. Relevance to clinical course and pathogenesis.

The cellular immune response to acetylcholine receptor from Torpedo electric organ was studied in 100 myasthenic patients and 41 healthy subjects. The mean stimulation index (SI) was 2 +/- 0.15 for the patients, and 1.06 +/- 0.08 for the controls. Stimulation was significantly greater when the test medium contained autologous serum rather than a standard universal serum (AB serum). Young patients were generally good responders (SI, 2.39 +/- 0.26), but older patients usually did not respond (mean SI, 1.18 +/- 0.13). Among the younger patients, men had higher responses than women (mean SI, 3.13 +/- 0.63 and 2.05 +/- 0.23, respectively). There was no correlation between degree of lymphocytic reactivity and duration or severity of symptoms.