Exposure to IFNs leads to a
modulation in the levels of many cellular proteins that mediate the pleiotropic effects of interferons. These effects may be mediated
by soluble factors or by cell-cell interactions involving specific membrane proteins. Deblandre et al. (1995) identified a 17-kD
membrane protein, IFI17, that was inducible on tumor cell lines by interferon-alpha (OMIM 147660) and, usually to a lesser extent, by
interferon-gamma (OMIM 147570).
drives the migration of PGCs from the mesoderm to endoderm.
Improved efficiency of female germline stem cell purification using Fragilis-based magnetic bead sorting. Zou K et al. The enrichment of female germ line stem cells (FGSCs) and the establishment of cell lines are influenced by the efficiency of cell purification. A previous study using mouse vasa homolog (MVH)-magnetic bead sorting for the isolation and purification of mouse FGSCs showed a relatively low efficiency. In this study, we tested three further proteins with the aim of improving the efficiency of FGSC purification. Immunofluorescence assays and magnetic sorting were performed using short-type PB-cadherin (Stpb-c), CD9, and interferon-inducible transmembrane protein 3 (Iftm3, Fragilis), all of which are expressed in germ cells. Although all three proteins were expressed in FGSCs, CD9 was unsuitable because of its lack of germ-line specificity, and Stpb-c was also unsuitable because of the unavailability of an appropriate primary antibody. The efficiency of FGSC purification was remarkably enhanced using the germline-specific protein Fragilis, compared with that using MVH. This new method for the purification of FGSCs may have extensive applications in stem cell studies and clinical research.
Expression regulated by
Comment
Ovarian localization
Primordial Germ Cell, female germ stem cell
Comment
Improvement in Isolation and Identification of Mouse Oogonial Stem Cells. Lu Z et al. (2015) Female germline stem cells (FGSCs) or oogonial stem cells (OSCs) have the capacity to generate newborn oocytes and thus open a new door to fight ovarian aging and female infertility. However, the production and identification of OSCs are difficult for investigators. Rare amount of these cells in the ovary results in the failure of the acquisition of OSCs. Furthermore, the oocyte formation by OSCs in vivo was usually confirmed using tissue sections by immunofluorescence or immunohistochemistry in previous studies. STO or MEF feeder cells are derived from mouse, not human. In our study, we modified the protocol. The cells were digested from ovaries and cultured for 2-3 days and then were purified by magnetic-activated cell sorting (MACS). The ovaries and fetus of mice injected with EGFP-positive OSCs were prepared and put on the slides to directly visualize oocyte and progeny formation under microscope. Additionally, the human umbilical cord mesenchymal stem cells (hUC-MSCs) were also used as feeder cells to support the proliferation of OSCs. The results showed that all the modified procedures can significantly improve and facilitate the generation and characterization of OSCs, and hUC-MSCs as feeder will be useful for isolation and proliferation of human OSCs avoiding contamination from mouse.////////// Stem cells were trypsinized and purified by MACS using Fragilis antibody //////////////////
To determine precisely how germ cells are specified, Saitou et al. (2002) performed a genetic screen between single nascent germ
cells and their somatic neighbors that share common ancestry. They demonstrated that fragilis, a member of the IFN-inducible
transmembrane protein family, marks the onset of germ cell competence, and they proposed that through homotypic association, it
demarcates germ cells from somatic neighbors.