Tehran University Medical Journal

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Background: This study was performed to investigate the rate of inner cell mass of blastocyst which obtain from culture of mouse two cell embryos in presence and absence of recombinant of human leukemia inhibitory factor.
Materials and Methods: ICR female mice that were between 6-8 weeks old received intra peritoneal injection of 7.5 IU of pregnant mare serum gonadotropine for super ovulation, this was followed by intra peritoneal administration of 7.5 of hCG 46-48 hours later. The mice were then mated to mature ICR male mice and were checked for vaginal plug 20 hours later. Female mice were killed by cervical dislocation 48-50 hours after hCG administration and after washing and flushing of the oviduct from the proximal end of the oviduct, two cell embryos were selected and collected by 100 microscopy. All two cell embryos were randomly divided in 4 groups (Groups A, B C and D) and culture in special media. Groups A: KSOM+AA, Groups B: KSOM+AA 500 IU/ml LIF. Groups C: KSOM+AA 1000 IU/ml LIF. Groups D: KSOM+AA 1500 IU/ml LIF media until 120 hours in Co2 incubator .After that time all blastocysts collected and the number of ICM was assessed by differential staining technology.
Results: The rates of ICM of blastocysts which obtain from groups A, B, C and D were 19 2.6, 28 4.4, 24 2.1, 26 2.2 respectively. This data indicated that the rate of ICM in groups B, C and D was statistically higher than group A (P=0.02) and also there was not statistically different between three groups of B, C and D.
Conclusion: Briefly leukemia inhibitory factor can improve the rate of ICM of blastocyst and we suggest that this factor is better added to blastocyst culture medium.

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Background: Leukemia inhibitory factor (LIF) is a group of secreted glycoproteins with molecular weights ranging from 38-67 kD, resulting from differential protein glycosylation. LIF is constitutively expressed at high levels in the human fallopian tube epithelium and has an important role in the motility and vitality of sperm. In the present study, the effect of human recombinant LIF on human sperm motility and survival in vitro was investigated.

Methods: Normal spermatozoa of 30 fertile men were collected and after preparation were incubated in Ham's F10+FCS 10% medium, containing various concentrations (0, 3, 5, 10, and 50 ng/ml) of LIF at 37 ºC under 5% CO2 for 6, 24 and 48 hours. Sperm motion characteristics were measured using a Makler chamber. Sperm survival was determined using the hypoosmotic swelling test. Collected data were analyzed by one-way ANOVA and LSD test using SPSS version 11. The difference in values were considered significant when p<0.05.

Results: Sperm motility was significantly higher after 24 h exposure to 5-10 ng/ml LIF (p<0.05). The survival rate of sperm was significantly prolonged when exposed to 50 ng/ml LIF (p<0.05). Nonprogressive motility and survival rate of sperm were significantly higher after 48 h exposure to 50 ng/ml and 10-50 ng/ml LIF, respectively. (p<0.05). There was no significant difference in progressive sperm motility during the 48 h exposure of sperm to the various concentrations of LIF.

Conclusion: According to our results, the effect of LIF on sperm motility and survival were dependent on the dose of LIF supplementation and the length of incubation.