Extraction of sp18 family membrane proteins on posterior head of bull sperm and the effect of anti-sp18 IgG on sperm motility and murine in vitro fertilization.
Bovine sperm heads were separated via ultrasonic treatment and centrifugation. Anti-bull sperm IgG was produced by immunizing rabbits with acrosome-reacted bull sperm heads. SDS PAGE patterns revealed that the main membrane proteins on acrosome-reacted bull sperm head were sp18 family, including 18, 16, and 14 kD, which represented about 64% of the total membrane proteins in bull sperm. Indirect immunofluorescence shown sp18 antigens primarily distributed in postacrosomal and proximal tail regions. Western blot analysis revealed that the anti-bull sperm IgG reacted with sp18 antigens in acrosome-reacted bull sperm head and bull seminal plasma. Anti-bull sperm IgG also reacted with 14, 16, 18, 42, 57 and 60 kD proteins in fresh bull, mouse and rabbit sperm. Anti-sp18 IgG caused agglutination of bull and rabbit sperm, but had no effect on murine sperm. In murine in vitro fertilization trials, preincubating capacitated sperm with 0.364 mg/ml of anti-sp18 IgG resulted in a decrease in the fertilization rate from 75.6% in the controls to 50.8% in the experimental groups (p < 0.001).
Gou
K M
KM
National Laboratory for Agrobiotechnology, China Agricultural University, Beijing, China.
Shang
L J
LJ
An
X R
XR
Lin
A X
AX
Ren
L M
LM
Chen
Y F
YF
D000177:Acrosome; D000818:Animals; D000941:Antigens / Q000276:immunology; D002417:Cattle; D005306:Fertilization / Q000276:immunology; D005455:Fluorescent Antibody Technique; D007074:Immunoglobulin G / Q000276:immunology*; D008297:Male; D008565:Membrane Proteins / Q000235:genetics / Q000276:immunology* / Q000502:physiology; D051379:Mice; D011817:Rabbits; D013077:Sperm Head / Q000502:physiology*; D013081:Sperm Motility
D000941:Antigens; D007074:Immunoglobulin G; D008565:Membrane Proteins