Clq binding circulating immune complexes in multiple sclerosis patients and their first-degree relatives: a...

Circulating Clq binding immune complexes were detected in 43% of sera from sporadic multiple sclerosis patients, in 52% of sera from the patients' first degree relatives and in 12% of normal sera studied, but not in 9 cases of familial multiple sclerosis nor in 24 of their 26 relatives. In sporadic cases, the presence of circulating immune complexes was not associated with any specific clinical form (progressive or remittent) nor with hypocomplementaemia. Circulating immune complexes were found more frequently in female than in males patients, but this sex difference was not found in their healthy relatives. These results indicate that sporadic cases differ from familial multiple sclerosis cases by a frequent occurence of circulating Clq binding immune complexes. Furthermore, the high incidence of immune complexes among relatives of patients with sporadic disease may result either from a genetically controlled immunological disorder or continuing response to an as yet unknow environmental factor.