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Understanding cell division and death during early embryonic development is crucial for insights into implantation and subsequent fetal development. This study successfully quantified the cell numbers in the trophectoderm and inner cell mass of mouse blastocysts, revealing a significant increase in trophectoderm cells and a slower growth in inner cell mass cells, alongside evidence of cell death predominantly in the inner cell mass.
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The numbers of cells in the trophectoderm (TE) and inner cell mass (ICM) of mouse blastocysts were counted by differentially labelling their nuclei with two polynucleotide-specific fluorochromes. Blastocysts recovered from the uterus at intervals between their formation early on Day 4 to the initial stages of implantation on day 5 were analysed. TE cell number increase was initially rapid, indicating some synchronisation of the sixth division, but slowed down progressively and plateaued on Day 5, possibly due to the onset of primary giant cell formation. ICM cell number increase was slower than the corresponding TE cells. As a result, TE cell number more than quadrupled, whereas ICM cell number only doubled over this period. Although the mitotic index of both populations of cells fell steadily, there was no significant difference between them. The decline in the proportion of ICM cells, therefore, is likely to be due to cell death, first detected in early blastocysts and predominantly located in the ICM. In addition, however, a contribution of ICM cells to the overlying polar TE cannot be excluded.
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References
Balakier H, Pedersen RA (1982) Allocation of cells to inner cell mass and trophectoderm lineages in preimplantation mouse embryos. Dev Biol 90:352–362
Barlow P, Owen DAJ, Graham C (1972) DNA synthesis in the preimplantation mouse embryo. J Embryol Exp Morphol 27:431–445
Bolton VN, Oades PJ, Johnson MH (1984) The relationship between cleavage, DNA replication and gene expression in the mouse 2-cell embryo. J Embryol Exp Morphol 79:139–163
Bowman P, McLaren A (1970a) Cleavage rate of mouse embryos in vivo and in vitro. J Embryol Exp Morphol 24:203–207
Bowman P, McLaren A (1970b) Viability and growth of mouse embryos after in vitro culture and fusion. J Embryol Exp Morphol 23:693–704
Copp AJ (1978) Interaction between inner cell mass and trophectoderm of the mouse blastocyst. J Embryol Exp Morphol 48:109–125
Copp AJ (1979) Interaction between inner cell mass and trophectoderm of the mouse blastocyst. II The fate of the polar trophectoderm. J Embryol Exp Morphol 51:109–120
Davies J, Hesseldahl H (1971) Comparative embryology of mammalian blastocysts. In: Blandau RJ (ed) The Biology of the Blastocyst, University of Chicago Press, London, pp 27–48
Dickson AD (1963) Trophoblastic giant cell transformation of mouse blastocysts. J Repr Fert 6:465–466
Dickson AD (1966) The form of the mouse blastocyst. J Anat 100:335–348
Ducibella T, Anderson E (1975) Cell shape and membrane changes in the eight-cell mouse embryo: Prerequisites for morphogenesis of the blastocyst. Dev Biol 47:45–58
El-Shershaby AM, Hinchliffe JR (1974) Cell redundancy in the zona-intact preimplantation mouse blastocyst: a light and electron microscopic study of dead cells and their fate. J Embryol Exp Morphol 31:643–654
Gamow EI, Prescott DM (1970) The cell life cycle during early embryogenesis of the mouse. Exp Cell Res 59:117–123
Gardner RL, Papaioannou VE, Barton SC (1973) Origin of the ectoplacental cone and secondary giant cells in mouse blastocysts reconstituted from isolated trophoblast and inner cell mass. J Embryol Exp Morphol 30:561–572
Glucksmann A (1951) Cell death in normal vertebrate ontogeny. Biol Rev 26:59–86
Handyside AH (1978) Time of commitment of inside cells isolated from preimplantation mouse embryos. J Embryol Exp Morphol 45:37–53
Handyside AH (1981) Immunofluorescence techniques for determining the number of inner and outer blastomeres in mouse morulae. J Reprod Immunol 2:339–350
Handyside AH, Barton SC (1977) Evaluation of the technique of immunosurgery for the isolation of inner cell masses from mouse blastocysts. J Embryol Exp Morphol 37:217–226
Handyside AH, Hunter S (1984) A rapid procedure for visualising the inner cell mass and trophectoderm nuclei of mouse blastocysts in situ using poly-nucleotide-specific fluorochromes. J Exp Zool 31:429–434
Hensleigh HC, Weitlauf HM (1974) Effect of delayed implantation on dry weight and lipid content of mouse blastocysts. Biol Reprod 10:315–320
Hogan B, Tilly R (1978) In vitro development of inner cell masses isolated immunosurgically from mouse blastocysts II. Inner cell masses from 3.5- to 4.0 day p.c. blastocysts. J Embryol Exp Morphol 45:107–121
Horvitz HR, Ellis HM, Sternberg PW (1982) Programmed cell death in nematode development. Neurosci Comment 1:56–65
Kelly SJ, Mulnard JG, Graham CF (1978) Cell division and cell alloction in early mouse development. J Embryol Exp Morphol 48:37–51
Kerr JFR, Wyllie AH, Currie AR (1972) Apoptosis: a basic biological phenomenon with wide ranging implications in tissue kinetics. Br J Cancer 26:239–257
Lehtonen E (1980) Changes in cell dimensions and intercellular contacts during cleavage-stage cell cycles in mouse embryonic cells. J Embryol Exp Morphol 58:231–249
MacQueen H, Johnson MH (1983) The fifth cell cycle of the mouse embryo is longer for smaller cells than for larger cells. J Embryol Exp Morphol 77:297–308
Manes C, Menzel P (1982) Spontaneous release of nucleosome cores from embryoblast chromatin. Dev Biol 92:529–538
Mukherjee AB (1976) Cell cycle analysis and X-chromosome inactivation in the developing mouse. Proc Natl Acad Sci (USA) 73:1608–1611
Nicholson GL, Yanagimachi R, Yanagimachi H (1975) Ultrastructural localization of lectin-binding sites on the zona pelucidae and plasma membranes of mammalian eggs. J Cell Biol 66:263–274
Quinn P, Barros C, Whittingham DG (1982) Preservation of hamster oocytes to assay the fertilizing capacity of human spermatozoa. J Repr Fert 66:161–168
Saunders JW (1966) Death in embryonic systems. Science 154:604–612
Sellens MH, Stein S, Sherman MI (1981) Protein and free amino acid content in preimplantation mouse embryos and in blastocysts under various culture conditions. J Repr Fert 61:307–315
Smith R, McLaren A (1977) Factors affecting the time of formation of the mouse blastocoele. J Embryol Exp Morphol 41:79–92
Solter D, Knowles BB (1975) Immunosurgery of mouse blastocyst. Proc Natl Acad Sci (USA) 72:5099–5102
Soltynska MS, Balakier H, Witkowska A, Karasiewicz J (1985) Binucleate cells in mouse morulae. Wilhelm Roux's Arch Dev Biol 194:173–177
Spindle AI (1978) Trophoblast regeneration by inner cell masses isolated from cultured mouse embryos. J Exp Zool 203:483–489
Wilson IB, Smith MS (1970) Primary trophoblastic invasion at the time of nidation. In: Hubinont PO, Leroy F, Robyn C, Leleux P (eds) Ovo-implantation, Karger, Basel, pp 1–8
Wyllie AH (1980) Glucocorticoid-induced thymocyte apoptosis is associed with endogenous endonuclease activation. Nature 284:555–556
Wyllie AH, Kerr JF, Currie AR (1980) Cell death: the significance of apoptosis. Int Rev Cytol 68:251–306
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Handyside, A.H., Hunter, S. Cell division and death in the mouse blastocyst before implantation. Roux's Arch Dev Biol 195, 519–526 (1986). https://doi.org/10.1007/BF00375893
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DOI: https://doi.org/10.1007/BF00375893