title: Immune complexes in healthy Nigerians.
abstract: Sera from 50 healthy Caucasians resident in Britain and 50 healthy Nigerians living aroung Zaria in Northern Nigeria were tested for the presence of circulating immune complexes by three different methods. Immune complexes could not be detected in the Caucasian sera but wer present in the Nigerian sera. However, only six of the 38 sera positive for complexes by the radio-bioassay method had significant anti-complementary activity. Examination of blood films from all six subjects showed malarial parasitaemia in five. The mean IgM level of the six anti-complementary sera was significantly higher than in the remaining 44 sera. After six weeks of malarial prophylaxis, sera from four of these subjects lost their anti-complementary activity and there was a parallel fall in the serum IgM values, suggesting that complexes related to malaria may have been present originally. Tests for detecting circulating immune complexes which fix complement may be useful in identifying clinically significant infections in apparently healthy Nigerians.
mesh_terms: D000936:Antigen-Antibody Complex; D003169:Complement Inactivator Proteins / Q000032:analysis; D006801:Humans; D007075:Immunoglobulin M / Q000032:analysis; D008288:Malaria / Q000276:immunology; D009549:Nigeria
chemical_list: D000936:Antigen-Antibody Complex; D003169:Complement Inactivator Proteins; D007075:Immunoglobulin M