Functionally active complement is present in human ovarian follicular fluid and can be activated by seminal plasma

• Published in: Clinical and experimental immunology 1992-07, Vol.89 (1), p.154-157
• Main Authors: PERRICONE, R., PASETTO, N., CAROLIS, C., VAQUERO, E., PICCIONE, E., BASCHIERI, L., FONTANA, L.
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Complement; complement activation; Complement Activation - physiology; Complement C1 Inactivator Proteins - analysis; Complement C3 - analysis; Complement C4 - analysis; Complement Factor B - analysis; Complement System Proteins - physiology; Female; Follicular Fluid - chemistry; Follicular Fluid - immunology; Fundamental and applied biological sciences. Psychology; Fundamental immunology; human ovarian follicular fluid; Humans; In Vitro Techniques; Male; Molecular immunology; ovulation; Semen - physiology; seminal plasma
• ISSN: 0009-9104; 1365-2249
• DOI: 10.1111/j.1365-2249.1992.tb06895.x

SUMMARY Human ovarian preovulatory follicular fluids (FF) from 10 women were analysed for their complement contents. Functionally active complement was detected in all the fluids studied in amounts similar to those present in normal human serum. Pooled FF was challenged by seminal plasma in order to determine whether seminal plasma could activate FF complement, the pattern of such an activation and the possible consequences on the reproductive function. FF complement activation occurred during the incubation with seminal plasma with features including alternative pathway activation, factor B and C3 conversion and reduction in total haemolytic complement, as well as an inhibition by seminal plasma of the FF complement response to a new activating challenge. Possible consequences for fertilization, implantation of a fertilized ovum and local defence mechanisms against viruses and bacteria are discussed.