A familial dysfunction of the eighth component of complement (C8)

摘要: Abstract A 6-year-old boy, who presented with hepatosplenomegaly, moderately elevated erythrocyte sedimentation rate, hypergammaglobulinemia, and eosinophilia, was found to have very low or undetectable serum C8 hemolytic activity. This activity restored normal by the addition of purified C8. Material cross-reacting antigenically present in showed reaction partial identity immunodiffusion analysis. Similar findings were observed an apparently healthy sibling. Further investigations on altered molecule proved its inability induce consumption C9 deficient following activation alternative pathway inulin. Both sera also contained inhibitor, which active only partially used at concentration diluted human serum. The inhibiting detected exclusion peak Sephadex G-200 gel filtration specifically removed anti-human C5 antiserum. Family studies activities antigenic levels both parents three other siblings propositus. Linkage abnormality HLA, Bf, C3, C7 uninformative, whereas linkage C6 excluded.