An ultrastructural study of in-vitro interaction of guinea-pig and mouse blastocysts with extracellular matrices.
Guinea-pig (intrusive) and mouse (displacement) blastocysts display different cellular mechanisms of implantation. Blastocysts were placed in CMRL-1066 supplemented with either 10 or 20% fetal calf serum, 0.1M L-glutamine and antibiotics and then transferred to dishes previously coated with either Matrigel or type I collagen. After culture for 48 or 72 h, the dishes were processed for transmission electron microscopy. Blastocysts had attached to both extracellular matrices by 48 h. Matrigel elicited minimal trophoblast cell activity. Trophoblast cell projections were oriented parallel to the Matrigel and displayed little invasive activity, but trophoblast cells displayed active interaction with type I collagen. By 72 h, trophoblast cells exhibited slender, anastomosing projections which extended into the collagen matrix. Bundles of microfilaments running parallel with the long axis of the projections were observed. The morphology of type I collagen was altered in the immediate vicinity of the trophoblast projections. The projections interdigitated and desmosomes developed between processes. Projections appeared to meet, fuse and entrap matrix. These results suggest that trophoblast cells do not significantly interact with Matrigel, but penetrate into type I collagen.
Wordinger
R J
RJ
Department of Anatomy and Cell Biology, University of North Texas, Texas College of Osteopathic Medicine, Fort Worth 76107-2690.
Brun-Zinkernagel
A M
AM
Jackson
T
T
D000818:Animals; D001672:Biocompatible Materials / Q000378:metabolism; D001755:Blastocyst / Q000502:physiology* / Q000648:ultrastructure; D002478:Cells, Cultured; D003094:Collagen / Q000378:metabolism / Q000502:physiology; D004338:Drug Combinations; D010064:Embryo Implantation / Q000502:physiology*; D005109:Extracellular Matrix / Q000502:physiology* / Q000648:ultrastructure; D005260:Female; D006168:Guinea Pigs; D007797:Laminin / Q000378:metabolism; D051379:Mice; D008854:Microscopy, Electron; D011509:Proteoglycans / Q000378:metabolism; D013997:Time Factors; D014327:Trophoblasts / Q000502:physiology
D001672:Biocompatible Materials; D004338:Drug Combinations; D007797:Laminin; D011509:Proteoglycans; C059485:matrigel; D003094:Collagen