Stimulation of human sperm capacitation by purified lipid transfer protein.
Lipid Transfer Protein I is recognized as a key component involved in high density lipoprotein metabolism. We have been studying lipid transfer in relation to sperm capacitation, a complex series of cell surface events required for the acrosome reaction and fertilization. We have previously shown that Lipid Transfer Protein I is present and active in the female reproductive tract. In the present study, we show that purified Lipid Transfer Protein I directly stimulates human sperm capacitation, but not the acrosome reaction, in the absence of other biological effectors. These results provide strong evidence for a novel role for Lipid Transfer Protein I and reveal, for the first time, a potent activator of capacitation, prior to the acrosome reaction.
Ravnik
S E
SE
Department of Obstetrics and Gynecology, University of Washington, Seattle 98195, USA.
Albers
J J
JJ
Muller
C H
CH
D000818:Animals; D002352:Carrier Proteins / Q000302:isolation & purification / Q000502:physiology*; D006224:Cricetinae; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D012709:Serum Albumin / Q000502:physiology; D013075:Sperm Capacitation / Q000502:physiology*; D013084:Sperm-Ovum Interactions
D002352:Carrier Proteins; D012709:Serum Albumin; C030363:lipid transfer protein