[Effect of TGF-beta1 on embryo implantation and development in mice in vitro].
OBJECTIVE
To investigate the role of TGF-beta1 in embryo implantation and development in vitro in mice.


METHODS
Mouse embryos at 2-cell stage were cultured in the media of M16 with exposure to different levels of TGF-beta1 (0, 1, 10 and 50 ng/mL). The percentage of embryos reaching fixed stages (early blastocyst, expanding blastocyst and hatched blastocyst) was monitored 68 h and 92 h after the culture. The expanding blastocys cultured for 68 h in M16 without TGF-beta1 and those with 10 ng/mL of TGF-beta1 were transferred to pseudopregnant mice. On the 6th day post transfer, the successful rates of implantation were counted. The level of IL-10/IFN-gamma in the serum and maternal-fetus interface of the mice was detected by ELISA on the 6th day post transfer.


RESULTS
TGF-beta1 improved embryo growth in vitro. TGF-beta1 at a level of 10 ng/mL had the maximum impact, with 15.6%, 68.09%, 1.42% of embryos reaching early, expanding, and hatched stage, respectively, 68 h after culture, and 6.38%, 28.37%, 53.19% of embryos reaching early, expanding, and hatched stage, respectively, 92 h after culture. The promoting effect declined when TGF-beta1 reached 50 ng/mL. The successful rate of implantation of embryos cultured in M16 with TGF-beta1 was significantly higher than those cultured in M16 without TGF-beta1 (35. 2% vs. 17.19%, P < 0.05). The embryos cultured in M16 with TGF-beta1 had significantly lower level of IFN-gamma in the maternal-fetus interface than those cultured in M16 without TGF-beta1 [(30.89 +/- 11.31) pg/mL vs. (43.23 +/- 18. 09) pg/mL, P < 0.053.


CONCLUSIONS
TGF-beta1 at an appropriate dose improves embryo implantation in mice in vitro. The mechanism may involve the improvement of the quality of embryos and their development, and decrease of IFN-gamma synthesis in maternal-fetal interface, a chemical that could cause Th2 bias.
Luo
Shan
S
Department of Obstetrics and Gynecology, West China Second Hospital, Sichuan University, Chengdu 610041, China.
Yin
Hai-ning
HN
Li
Shang-wei
SW
D000818:Animals; D001755:Blastocyst / Q000166:cytology / Q000187:drug effects; D046149:Embryo Culture Techniques; D010064:Embryo Implantation / Q000187:drug effects*; D047108:Embryonic Development / Q000187:drug effects*; D005260:Female; D007371:Interferon-gamma / Q000097:blood; D016753:Interleukin-10 / Q000097:blood; D008297:Male; D051379:Mice; D011247:Pregnancy; D053773:Transforming Growth Factor beta1 / Q000494:pharmacology*
C556062:IL10 protein, mouse; D053773:Transforming Growth Factor beta1; D016753:Interleukin-10; D007371:Interferon-gamma