C1q and immune complexes in liver cirrhosis sera.

The highest mean value of the serum C1q concentrations among chronic liver diseases was obtained in patients with liver cirrhosis (LC). C1q serum levels seemed to increase along the progression of liver damage. Serum levels of C1q and CH50 in patients with LC and systemic lupus erythematosus (SLE) were simultaneously estimated. No correlation between C1q and CH50 levels was observed in LC sera, while a significant correlation was demonstrated in SLE sera. It could be suggested that the mechanism for the low CH50 in LC sera seemed different from that in SLE sera, and that the activation of classical complement pathway was not the predominant cause in LC sera. Correlations of serum levels between immune complexes and C1q were examined in patients with LC and SLE. It could be deduced from the results of a positive correlation in LC sera and the reverse tendency in SLE sera that the significances of C1q and immune complexes in LC sera differed from those in SLE sera.