Cross-linking of Qa-2 protein, the Ped gene product, increases the cleavage rate of C57BL/6 preimplantation mouse embryos.
The Qa-2 protein, a glycosylphosphatidylinositol (GPI)-linked major histocompatibility complex (MHC) Class Ib molecule found on the surface of mouse T-cells and preimplantation embryos, is the product of the preimplantation embryo development (Ped) gene. The Ped gene regulates the rate of early embryonic development and subsequent embryo survival. T-cells treated with anti-Qa-2 monoclonal antibody (mAb) and cross-linked with a secondary antibody, in the presence of a co-stimulatory signal, undergo increased proliferation. The purpose of this study was to determine whether cross-linking of Qa-2 similarly affects preimplantation embryos. We cross-linked Qa-2 protein on the surface of C57BL/6 2-cell and 8-cell embryos, in the presence of 4/5-phorbol-12-myristate-13-acetate (PMA), and assessed the percentage of embryos reaching the blastocyst stage, the percentage hatching from the zona pellucida, [(3)H-thymidine] incorporation into DNA, and the total number of cells per embryo as measures of embryonic cleavage rate. Both 2-cell and 8-cell embryos increased their cleavage rates 48 h after cross-linking of Qa-2, compared with control embryos (P < 0.05). Our results indicate that a Qa-2 protein cross-linking mechanism may be one way by which this protein regulates the rate of preimplantation mouse embryo development.
McElhinny
A S
AS
Department of Biology, Northeastern University, Boston, MA 02115, USA.
Warner
C M
CM
D000818:Animals; D000911:Antibodies, Monoclonal / Q000378:metabolism / Q000494:pharmacology; D002478:Cells, Cultured; D003432:Cross-Linking Reagents; D004622:Embryo, Mammalian / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism*; D047108:Embryonic Development / Q000502:physiology*; D005260:Female; D015395:Histocompatibility Antigens Class I / Q000276:immunology / Q000378:metabolism*; D008213:Lymphocyte Activation / Q000187:drug effects; D051379:Mice; D008810:Mice, Inbred C57BL; D011247:Pregnancy; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D000911:Antibodies, Monoclonal; D003432:Cross-Linking Reagents; D015395:Histocompatibility Antigens Class I; C032907:Q surface antigens; D013755:Tetradecanoylphorbol Acetate