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Published on: October 24, 2025
Expression of complement system regulatory molecules in the endometrium of normal ovulatory and hyperstimulated women
Rosana Rita Nogawa Fonzar-Marana1, Rui Alberto Ferriani, Sandro Gomes Soares
1Department of Gynecology and Obstetrics, School of Medicine of Ribeirao Preto, University of São Paulo, Ribeirao Preto, Brazil.
Abstract:
The present study describes the temporal expression of complement regulatory molecules membrane cofactor protein (MCP), decay accelerating factor (DAF), CR1, and CD59 in the human endometrium throughout the normal menstrual cycle and in patients submitted to ovarian hyperstimulation. During its proliferative phase, the endometrium expresses MCP, with increased expression during the secretory phase. Phase-dependent expression also was observed for DAF and CD59, mainly in the secretory phase. Expression of CR1 was not detected. These results suggest the presence of complement system activity during the menstrual cycle, with greater expression of regulatory molecules during the secretory phase to protect the epithelial integrity of human endometrium.
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