ANTIIDIOTYPIC T-CELLS IN EARLY STAGES OF MYASTHENIA-GRAVIS - INCREASEIN THE NUMBER AND PREVALENCE CORRELATED TO CLINICAL IMPROVEMENT IN PATIENTS

An idiotypic network involving T and B cells bearing complementary str uctures has been suggested to be important for the regulation of immun e response in healthy and disease situations. A previous study by the authors has demonstrated the presence of a relatively higher concentra tion of anti-idiotypic antibodies than of idiotypic antibodies in earl y myasthenia gravis (MG), suggesting that the development of an anti-i diotypic immunity is important in early MG. The present study was cond ucted to examine the cellular components of thr idiotypic network in t he same situation. T and B cells reactive to acetylcholine receptor (A ChR) or io a disease-related idiotype and ro an anti-idiotype were ana lysed in seven patients with early MG at various times ater the start of the disease. The results show that a significant increase in the nu mber of idiotype-reactive interferon-gamma-secreting T cells and a shi ft from AChR-reactive to idiotype- and/or anti-idiotype-reactive T cel ls in the patients at 6 month follow-up were noted. Such changes seem to correlate to a clinical improvement in the patients. The enhanced a nti-idiotypic T-cell response and the clinical improvement in the pati ents may speak in favour of a role for the anti-idiotypic immunity in controlling the autoimmune response in MG, i.e., down-regulating autoa ntibody-producing B cells and idiotypic (AChR-specific) T cells. Thus, an immune intervention towards the enhancement of the anti-idiotypic immunity in patients might br a rewarding approach, Further studies wi th regard io cell interactions and immune regulations in the network a re warranted.