Biomaterial Database

Ultrastructure of the attachment of Cryptosporidium sporozoites to tissue culture cells. 1988

R Lumb, and K Smith, and P J O'Donoghue, and J A Lanser

Division of Clinical Microbiology, Institute of Medical and Veterinary Science, Adelaide, South Australia.

The attachment of Cryptosporidium sporozoites to Madin-Darby canine kidney (MDCK) cells was examined using transmission electron microscopy. As the anterior end of the sporozoite came into close proximity to the MDCK cell, the host cell membrane evaginated around the sporozoite, forming a parasitophorous vacuole. A dense band formed below the host cell membrane at the site nearest to the conoid. Variably electron-dense material was apparently released from the conoid and a large membrane-bound vacuole was formed in the anterior end of the sporozoite, displacing the typical anterior electron-dense organelles (rhoptries and micronemes). The outer membrane of the sporozoite pellicle then fused with the host cell membrane immediately adjacent to the conoid. The membrane surrounding the anterior vacuole was also fused with the common host-parasite membrane, forming Y-shaped membrane junctions where each limb was a unit membrane. A direct link was thereby established between the anterior vacuole of the sporozoite and the host cell cytoplasm. The anterior vacuole membrane separating the sporozoite and the host cell cytoplasm was the precursor of the feeder organelle.

UI	MeSH Term	Description	Entries
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D002448	Cell Adhesion	Adherence of cells to surfaces or to other cells.	Adhesion, Cell,Adhesions, Cell,Cell Adhesions
D002460	Cell Line	Established cell cultures that have the potential to propagate indefinitely.	Cell Lines,Line, Cell,Lines, Cell
D003044	Coccidia	A subclass of protozoans commonly parasitic in the epithelial cells of the intestinal tract but also found in the liver and other organs. Its organisms are found in both vertebrates and higher invertebrates and comprise two orders: EIMERIIDA and EUCOCCIDIIDA.	Coccidias
D003458	Cryptosporidium	A genus of coccidian parasites of the family CRYPTOSPORIDIIDAE, found in the intestinal epithelium of many vertebrates including humans.	Cryptosporidiums
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia