Analysis of anti-C1q antibodies in normal and pathological pregnancies

Analysis of anti-C1q antibodies in normal and pathological pregnancies C. Agostinis1, A. Mangogna2, O. Radillo1, G. Ricci1, R. Bulla2. 1. Institute for Maternal and Child Health, IRCCS Burlo Garofolo, 34137, Trieste, Italy; 2. Department of Life Sciences, University of Trieste, 34127, Trieste, Italy. PROBLEM C1q, the recognition molecule of the classical pathway of the complement system plays foundamental roles in pregnancy. C1q has been shown to promote trophoblast endovascular and interstitial invasion and is involved in the clearance of immune complexes and apoptotic bodies. Lack of C1q is characterized by poor trophoblast invasion and pregnancy failure. This molecule can be also the target of an antibody response: anti‐C1q antibodies are present in several infectious and autoimmune diseases. The presence of these auto-antibodies has been detected also in 2 to 8% of the general population. The aim of this study was to evaluate the presence and the circulating levels of anti-C1q Ab in pre-eclamptic (PE) patients compared to healthy pregnant women. METHOD Levels of anti‐C1q antibodies were analyzed by ELISA in PE and control sera obtained in the first and third trimester of pregnancy. RESULTS Anti-C1q antibodies were detected in both normal and PE sera. Higher levels of these antibodies were present in the first trimester compared to term normal pregnant sera. Early onset PE patients showed higher levels of anti-C1q antibodies compared to late onset PE patients. CONCLUSION Anti-C1q antibody levels increased during the first trimester of pregnancy. The level of these antibodies was higher in the sera of some early onset PE patients. These data indicates a possible role of anti-C1q antibodies in the control of pregnancy and in the pathogenesis of PE. The role played by these antibodies at foeto-maternal interface requires further investigation.