title: Effects of lactoferrin, a protein present in the female reproductive tract, on parameters of human sperm capacitation and gamete interaction.
abstract: In a recent study, lactoferrin (LF) was detected in human oviductal secretion. The protein was able to bind to oocytes and sperm, and modulated gamete interaction. The aim of the present study was to investigate the effect of LF on parameters related to human sperm capacitation and sperm-zona pellucida interaction. Semen samples were obtained from healthy normozoospermic donors (n = 7). Human follicular fluids and oocytes were collected from patients undergoing in vitro fertilization. Motile sperm obtained by swim-up were incubated for 6 or 22 h under capacitating conditions with LF (0-100 μg/mL). After incubations, viability, motility, presence of α-d-mannose receptors (using a fluorescent probe on mannose coupled to bovine serum albumin), spontaneous and induced acrosome reaction (assessed with Pisum sativum agglutinin conjugated to fluorescein isothiocyanate), and tyrosine phosphorylation of sperm proteins were evaluated. Sperm-zona pellucida interaction in the presence of LF was investigated using the hemizone assay. The presence of LF did not affect sperm viability or motility, but caused a dose-dependent significant decrease in sperm α-d-mannose-binding sites, and the effect was already significant with the lowest concentration of the protein used after 22 h incubation. Dose-dependent significant increases in both induced acrosome reaction and tyrosine phosphorylation of sperm proteins were observed in the presence of LF. The present data indicate that LF modulates parameters of sperm function. The inhibition of gamete interaction by LF could be partially explained by the decrease in sperm d-mannose-binding sites. The presence of the LF promoted sperm capacitation in vitro.
authors.affiliation: Area of Clinical Biochemistry, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina.
authors.forename: C M
authors.initials: CM
authors.lastname: Zumoffen
authors.affiliation: Area of Clinical Biochemistry, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina.
authors.forename: E
authors.initials: E
authors.lastname: Massa
authors.affiliation: Area of Clinical Biochemistry, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina.
authors.forename: A M
authors.initials: AM
authors.lastname: Caille
authors.affiliation: Area of Clinical Biochemistry, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina.
authors.forename: M J
authors.initials: MJ
authors.lastname: Munuce
authors.affiliation: Area of Clinical Biochemistry, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina.
authors.forename: S A
authors.initials: SA
authors.lastname: Ghersevich
mesh_terms: D020101:Acrosome Reaction / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D018920:Coculture Techniques; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007781:Lactoferrin / Q000378:metabolism / Q000494:pharmacology*; D037181:Lectins, C-Type / Q000187:drug effects / Q000378:metabolism; D008297:Male; D000090323:Mannose Receptor; D037241:Mannose-Binding Lectins / Q000187:drug effects / Q000378:metabolism; D009865:Oocytes / Q000187:drug effects* / Q000378:metabolism; D010766:Phosphorylation; D011956:Receptors, Cell Surface / Q000187:drug effects / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D013075:Sperm Capacitation / Q000187:drug effects*; D013081:Sperm Motility / Q000187:drug effects; D013084:Sperm-Ovum Interactions / Q000187:drug effects*; D013094:Spermatozoa / Q000187:drug effects* / Q000378:metabolism; D013997:Time Factors; D014443:Tyrosine; D055815:Young Adult
chemical_list: C490098:LTF protein, human; D037181:Lectins, C-Type; D000090323:Mannose Receptor; D037241:Mannose-Binding Lectins; D011956:Receptors, Cell Surface; D014443:Tyrosine; D007781:Lactoferrin
keywords: Lactoferrin; acrosome; capacitation; reproductive tract; sperm function