Spermagglutination by Bacteria: Receptor‐Specific Interactions

Abstract

ABSTRACT: The influence of genital infection on infertility has yet to be elucidated. We examined receptor—ligand interactions between sperm and Escherichia coli from patients with prostatitis. Two E. coli surface adhesins (P‐fimbriae, type 1 fimbriae) and their specific receptor saccharides (α‐galp‐1–4‐β‐galp‐O‐methyl [gal‐gal], mannose) were evaluated. Bacterial concentrations of 104 caused spermagglutination. P‐fimbriae caused tail—tail spermagglutination that was inhibited by gal‐gal. D‐mannose concentrations are highest in the acrosomal region and type 1 fimbriae caused head—head agglutination that was inhibited by mannose. Strains with both fimbriae caused head—head and tail—tail agglutination that was inhibited by a mannose/gal‐gal combination. E. coli agglutinated 40–75% of motile sperm. Seminal fluid provided 50–100% protection, with lower effectiveness against type 1 fimbriae. Understanding bacteria—spermatozoa interactions at the receptor—ligand level holds potential for treatment of infertility and development of spermagglutinating contraceptives.