Insulin-like Growth Factor II Induces Migration And Invasion Of Human First-trimester Cytotrophoblasts

Objective To investigate the migration and invasion roles of recombination human Insulin-like growth factor II (IGF-II) in first-trimester human cytotrophoblast cells,Methods 1. Six Healthy placental tissues between six and eight weeks of gestation were obtained and digested by trypsin. The cells were purified by percoll separating solution, and were incubated in cell culture flask covered with matrigel(matrigel:DMEM=1:2)in order to obtain high purity trophoblast cell.2. The in vitro cytotrophoblast cells migration model was set up by wound scratch assay and the cytotrophoblast cells were incubated with appropriate concentration of IGF-II and were divided into two groups: dose-dependent group (0μg /L IGF-II,10.5μg /L IGF-II,26.5μg /L IGF-II,52.5μg /L IGF-II,112.5μg /L IGF-II); time-response group (6h;12h;24h); Examining reduced distance assessed the amount of migration cells.3. The in vitro cytotrophoblast cells invasion model was set up by Transwell assay and the cytotrophoblast cells were incubated with appropriate concentration of IGF-II and were divided into two groups: dose-dependent group (0μg /L IGF-II,10.5μg /L IGF-II,26.5μg /L IGF-II,52.5μg /L IGF-II,112.5μg /L IGF-II),were incubated with 48h; time-response group (12h;24h;48h;72h),with the same concentration of 52.5μg /L IGF-II; Examining superficies inferia cells assessed the amount of invasion cells.Results 1. The purity of trophoblast cells purified by percoll separating solution was over 90%.2. Dose-dependent migration assay showed that the reduced distance was increased with the increase of dose , indicating that the amount of migration cells increased with the increase of dose. The maximal response was obtained at 52.5μg /L IGF-II, but there was no difference compared with 112.5μg /L IGF-II (P>0.05). The difference of each group was significant comparing with control (P<0.05). Time-course migration assay indicated the number of migration cells increased with the prolonging of time ,and the optimum time for maximum migration of the trophoblast cells was 24h, the difference was significant comparing with other groups (P<0.01).3. Dose-dependent invasion assay showed that the superficies inferia cells was increased with the increase of dose , indicating that the amount of invasion cells increased with the increase of dose. The maximal response was obtained at 52.5μg /L IGF-II, but there was no difference compared with 112.5μg /L IGF-II (P>0.05). The difference of each group was significant comparing with control (P<0.05). Time-course migration assay indicated the number of migration cells increased with the prolonging of time ,and the optimum time for maximum migration of the trophoblast cells was 48h, but there was no difference compared with 72h, the difference was significant comparing with other groups (P<0.05).Conclusion 1. High purity of trophoblast cells was obtained by purifying with percoll separating solution.2. IGF-II significantly stimulated trophoblast cells migration in a dose-dependent and time-response manner, 52.5μg /L IGF-II can significantly stimulate the migration of trophoblast cells.3. IGF-II significantly stimulated trophoblast cells invasion in a dose-dependent and time-response manner, 52.5μg /L IGF-II can significantly stimulate the invasion of trophoblast cells.