Project/Area Number |
09671679
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Obstetrics and gynecology
|
Research Institution | Osaka University |
Principal Investigator |
OHASHI Kazutomo Osaka University Medical School, Lecturer, 医学部, 講師 (30203897)
|
Co-Investigator(Kenkyū-buntansha) |
SHIMOYA Kouichiro Osaka University Medical School, Assistant Professor retire, 医学部, 助手 (40291950)
SAJI Fumitaka Osaka University Medical School, Associate Professor retire, 医学部, 助教授 (90093418)
TOKUGAWA Yoshihiro Osaka University Medical School, Assistant Professor, 医学部, 助手 (70283786)
AZUMA Chihiro Osaka University Medical School, Lecturer, 医学部, 講師 (20151061)
|
Project Period (FY) |
1997 – 1998
|
Project Status |
Completed (Fiscal Year 1998)
|
Budget Amount *help |
¥2,900,000 (Direct Cost: ¥2,900,000)
Fiscal Year 1998: ¥1,300,000 (Direct Cost: ¥1,300,000)
Fiscal Year 1997: ¥1,600,000 (Direct Cost: ¥1,600,000)
|
Keywords | human spermatozoa / human oocyte / acrosome reaction / fertilization / CD46 |
Research Abstract |
CD46 (membrane cofactor protein) acts to down-regulate complement cascade activity by binding complement components C3b and also acts as the cell surface receptor for measles virus.The extra-cytoplasmic components of the molecule are composed of four short consensus repeat (SCR) regions.SCR-1 is related to the down-regulation of complement activity and SCR-2 is a main domain of the measles virus fusion receptor.In our study, we revealed a novel SCR-3 related function in fertilization.We performed the hamster oocyte penetration test using the addition of antibodies against SCR-1, 2, and 3 of CD46 molecule.The anti-SCR-3 monoclonal antibodies reduced the penetration of human spermatozoa to the hamster oocytes in a dose-dependent manner, but did not inhibit the sperm binding to the oocytes.We concluded that CD46, especially SCR-3, was a fusion receptor of human spermatozoa to the oocyte and a marker of the fertilization capacity of human spermatozoa.We then developed a new method to assess the fertilization capacity of human spermatozoa by a two-color staining using fluorescein isothiocyanate-conjugated Pisum sativum agglutinin (FITC-PSA) and anti-CD46 monoclonal antibody.The two-color staining revealed four staining patterns of acrosomal region.We defined PSA-positive/CD46 negative spermatozoa as acrosome-intact, PSA-negative/CD46 positive spermatozoa as acrosome-reacted, PSA-negative/CD46 negative spermatozoa as acrosome-damaged.The percentage of acrosome-reacted spermatozoa increased more rapidly than those of acrosome-damaged spermatozoa with the incubation time.The percentage of acrosome-reacted spermatozoa at the 4-hour incubation was related to fertilization in the clinical human IVF.
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