Effect of macrophages on the differentiation of mouse induced pluripotent stem cells into hepatic progenitor cells / 临床肝胆病杂志

ObjectiveTo investigate the effect of macrophages (MCs) on the differentiation of mouse induced pluripotent stem cells (iPSCs) into hepatic progenitor cells (HPCs). MethodsA total of 24 C57BL/6N mice were used to obtain MCs by peritoneal irrigation, and the supernatant was collected to obtain the conditioned medium of MCs (MC-CDM). Activin A, bone morphogenetic protein 4, and fibroblast growth factor were used to induce the differentiation of mouse iPSCs into HPCs. The differentiation of HPCs were randomly divided into control group (normal medium) and experimental group (MC group; use of MC-CDM medium on day 5 of induction). Morphology, immunofluorescence assay, and Western blot were used to compare the morphology of HPCs and the expression of related proteins between the control group and the MC group. The t-test was used for comparison of continuous data between two groups. ResultsHPCs derived from iPSCs were established in vitro, and HPCs had the potential to differentiate into hepatocytes. Immunofluorescence assay showed that compared with the D12 control group, the D12 MC group had a significant increase in the protein expression of the HPC-specific protein CK19 (0.901±0.072 vs 0.686±0.097, t=-3.093, P＜0.05). Western blot showed that compared with the D12 control group, the D12 MC group had a significant increase in the protein expression of the HPC-related protein CK19 (1.922±0.103 vs 1.448±0.012, t =-7.881, P ＜005), as well as a significant increase in the protein expression of the autophagy-related protein LC3 (1.392±0.042 vs 1.101±0048, t =-5.978, P＜005). ConclusionMCs can promote the differentiation of mouse iPSCs into HPCs, possibly by increasing the autophagy level of HPCs.

Histocompatibility and imprinting status of parthenogenetic embryonic stem cells / 生物医学工程学杂志

The parthenogenetic embryonic stem cells (pESCs) derived from parthenogenetic embryos have the totipotency and proliferation capacity similar to those of the fertilized embryonic stem cells (fESCs). Therefore, the establishment of pESCs line avoids destroy of embryo and kence may make pESCs less concerns with political and ethical issues. These cells are characterized by their histocompatibility with the oocyte donor and therefore is more suitable for cell and tissue replacement therapy. In addition, because of the typical imprinting status, pESCs also provide a valuable in vitro model system for studying the molecular mechanisms in genomic imprinting.

Transgenic mouse fetus generated from embryonic stem cells by tetraploid embryo complementation / 解剖学报

Objective To use tetraploid embryo complementation combined with gene transfer to produce genetically modified embryonic stem cells (EsCs) clones. Methods In this study, EGFP was introduced into ESCs by electroporation, and transfected positive cells were selected by G418 resistance. The tetraploid embryos were obtained from diploid blastomere electrofusion which preformed at 2-cell stage. Afterwards, 19-21 EGFP-ESCs were inserted into each tetraploid blastocyst cavity by piezo drilled microinjection,then the injected blastocysts were transferred into the uterus of pseudo-pregnancy at 2.5-day or the oviduct of 0.5-day female mice. Results The transfected ESCs maintained normal karyotype even after long-term passage (2n=40). The rate of fusion was 95.07%, and the developmental rate of tetraploid blastocyst was 95%.Totally 410 injected blastocysts were obtained. Unfortunately, we have not got any vital offsprings, except 151 implantation sites (pseudo-pregnancy 2.5 days:29.41%;the oviduct of half one day:64.37%). Furthermore, scattered EGFP expressions in transgenic fetus were observed under invert fluorescent microscope. Conclusion The transfected ESCs were observed in transgenic fetus, and the implantation rate in oviduct was higher than that in uterine.