Effect of leukemia inhibitory factor (LIF) on the quality of in vitro produced mouse blastocysts and subsequent derivation of embryonic stem (ES) cells.

OBJECTIVE: To determine the effect of leukemia inhibitory factor (LIF) on the quality of in vitro produced mouse blastocyst and the efficiency of embryonic stem (ES) cell derivation. DESIGN: Experimental study SETTING: Reproductive Medicine Unit, Department of Obstetrics and Gynecology, Faculty of Medicine, Chulalongkorn University MATERIAL AND METHOD: In vivo fertilized zygotes were collected and subjected to in vitro culture in potassium simplex optimized medium (KSOM) containing 1,000 unit/ml LIF. The developmental ability of the zygote to blastocyst-stage and the cell numbers in blastocysts were evaluated Expanded blastocysts developed in different culture media were subsequently subjected to ES cell derivation. MAIN OUTCOME MEASURE (s): The influence of LIF on the quality of and the total cell numbers of blastocyst developed in vitro. RESULTS: Supplementation of LIF in KSOM increased the rate of hatching blastocysts (63.8% vs. 53.7%; p < 0.05) and total cell numbers (91.4 +/- 15.0 vs. 85.1 +/- 7.7; p < 0.05) compared to KSOM alone. ES cells were obtained 66.7% from blastocysts developed in KSOM-LIF versus 41.7% in KSOM (p > 0.05). Established ES cell lines showed typical colony and characteristics of pluripotent murine ES cells. CONCLUSION: LIF improved the quality of in vitro produced blastocysts but not enhanced ES cell derivation.

Preliminary study on somatic cell nuclear transfer in rabbits in Thailand.

The objective of the study was to develop the somatic nuclear transfer technique by using rabbits as the model. The oocyte recipients aged 16 h post coitus were collected surgically from 20 superovulated rabbit doe with 28 and 40 mg Follicle Stimulating Hormone (FSH) after mating with a vasectomized male. The metaphase II plate and 1st polar body of oocyte was later aspirated by enucleated micropipette under an inverted microscope. A single donor cell; cumulus cell or cultured or frozen fibroblast cell from passage 1 to 9 were transferred to enucleated oocyte and fused with triple DC pulses, 3.2 kv, 20 micros. The fused embryos were cultivated in TCM 199 NaHCO3 + 10 per cent fetal calf serum (FCS) for 4 days. The cleavage rate (2-cell stage) was 37.2 per cent (32/86) from eight experiments, and 18.8 per cent (6/32) developed to the early morula stage. This study also indicated that the enucleation pipette and the somatic cell type influenced the success.