Purification and embryotropic roles of tissue inhibitor of metalloproteinase-1 in development of "HanWoo" (Bos taurus coreanae) oocytes co-cultured with bovine oviduct epithelial cells

This study was conducted to purify a tissue inhibitor of metalloproteinase (TIMP)-1 in a serum-free medium conditioned with bovine oviduct epithelial cells (BOEC) and to evaluate its effect on development of "HanWoo" (Bos tau rus coreanae) embryos to the blastocyst stage. In the first study using SDS -PAGE electrophoresis, the presence of 32 kDa proteins, which contains TIMP -1, was detected in the medium conditioned with BOEC, and TIMP-1 was then p urified from the medium by gel filtration and HPLC techniques. When examine d TIMP-1 secretion, fluorescent foci indicating the secretion of TIMP-1 wer e found after stained BOEC with fluorescein isothiocyanate. In the next exp eriment, two-cell embryos derived from in vitro-fertilization were cultured in a serum-free medium, to which 0, 1.25, 2.5 or 5 mu g/ml of purified TIM P-1 was supplemented. More (P<0.05) embryos developed to the morula and bla stocyst stages after the addition of 2.5 mu g/ml to culture medium than aft er no addition. In conclusion, our data indicate that BOEC secrete TIMP-1 a nd this glycoprotein promotes the prehatched development of "HanWoo" embryo s derived from in vitro-fertilization.