Changes in glycoconjugate-lectin binding characteristics of in vitro and in vivo mouse blastocysts.
OBJECTIVE
To investigate the influence of embryo culture, on blastocysts cultured from the zygote stage, on blastocyst cell surface glycoconjugates as an indicator of cellular metabolism.


METHODS
Eleven fluorescein isothiocyanate (FITC)-labelled lectins, which recognize different oligosaccharide structures, were applied to zona pellucida intact and zona pellucida free blastocysts which had developed either in vivo or in vitro. The differential binding patterns for the zona pellucida, trophectoderm and inner cell mass were determined using fluorescence microscopy.


RESULTS
With the exception of wheat germ agglutinin (WGA) and Limax flavus agglutinin (LFA) the remaining nine lectins bound less intensely to the zona pellucida of the in vitro blastocysts compared with the in vivo blastocysts. The trophectoderm from both groups bound seven lectins with equal intensity, of the remaining four Lotus tetragonolbus agglutinin (LTA), Bandeiraea simplicifolia 4 (BSB4), Phaseolus vulgaris agglutinin P (PHA-P) and Limulus polyphemus agglutinin (LPA) demonstrated differential binding. The inner cell mass from the two blastocyst groups bound only three lectins identically, peanut agglutinin (PNA), Bandeiraea simplicifolia 4 (BSB4) and Dolichos biflorus agglutinin (DBA).


CONCLUSIONS
Oviductal glycoproteins contribute to the zona pellucida glycoprotein content during early development, however embryo culture from the zygote stage may not provide adequate substrates for normal inner cell mass glycoconjugate biosynthesis.
Legge
M
M
Department of Biochemistry, University of Otago, Dunedin, New Zealand.
D000818:Animals; D001757:Blastomeres / Q000378:metabolism; D002478:Cells, Cultured; D003470:Culture Media; D005260:Female; D037102:Lectins / Q000032:analysis; D008562:Membrane Glycoproteins / Q000032:analysis; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008856:Microscopy, Fluorescence; D012680:Sensitivity and Specificity
D003470:Culture Media; D037102:Lectins; D008562:Membrane Glycoproteins