DETERMINATION OF CIRCULATING IMMUNE-COMPLEXES - COMPARISON BETWEEN AGGLUTINATION INHIBITION AND C1Q PRECIPITATION IN POLYETHYLENE-GLYCOL-EDTA

  • 1 January 1978
    • journal article
    • research article
    • Vol. 26  (1) , 73-79
Abstract
Three different methods for the determination of circulating immune complexes were compared: precipitation of radioiodinated Clq [q fragment of complement component] in polyethyleneglycol-EDTA, and inhibition of Ig[immunoglobulin]G-coated latex particles agglutination by C1q or polyclonal rheumatoid factor. Normal values and their upper limits as well as the reproducibility of each technique were presented. The effect of several factors was investigated: age, sex, anticoagulants, freezing and thawing and contamination by DNA or endotoxin. Comparison of the results obtained with normal or pathological [human] sera revealed a positive correlation between the 3 techniques. Discrepancies noted with some sera make use of at least 2 different methods highly recommendable for the study of circulating immune complexes in disease.