Biomaterial Database

Culture of isolated bovine megakaryocytes on reconstituted basement membrane matrix leads to proplatelet process formation. 1990

K S Topp, and F Tablin, and J Levin

Department of Anatomy, School of Veterinary Medicine, University of California, Davis 95616.

We have enriched for bovine megakaryocytes and identified a culture system that may provide an in vitro model for platelet formation. Mature megakaryocytes with an unusually high ploidy distribution were obtained after differential centrifugation and velocity sedimentation of bone marrow cells through gradients of bovine serum albumin (BSA). The cell membranes of isolated megakaryocytes and megakaryocytes in vivo stained with antisera to human platelets and human platelet membrane GPIIIa. The microenvironment of bovine megakaryocytes in vivo was investigated using antibodies to types I and IV collagen and laminin. In an attempt to duplicate the microenvironment in vitro, bovine megakaryocytes were cultured on a reconstituted basement membrane matrix (Matrigel). The cells adhered to the gel, extended radial lamellipodia, and occasionally formed lengthy pseudopodia. Ultrastructural examination of these cells showed widening and coalescence of the megakaryocyte demarcation membranes (DMS), and inclusion of platelet granules, thin filaments, and microtubules in the processes. Very few DMS vesicles were present distally in the processes. The culture of megakaryocytes on a reconstituted basement membrane may closely model the in vivo megakaryocyte microenvironment and allow the study of thrombocytopoiesis in vitro.

UI	MeSH Term	Description	Entries
D007797	Laminin	Large, noncollagenous glycoprotein with antigenic properties. It is localized in the basement membrane lamina lucida and functions to bind epithelial cells to the basement membrane. Evidence suggests that the protein plays a role in tumor invasion.	Merosin,Glycoprotein GP-2,Laminin M,Laminin M Chain,Chain, Laminin M,Glycoprotein GP 2,M Chain, Laminin
D008533	Megakaryocytes	Very large BONE MARROW CELLS which release mature BLOOD PLATELETS.	Megakaryocyte
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
D011003	Ploidies	The degree of replication of the chromosome set in the karyotype.	Ploidy
D001792	Blood Platelets	Non-nucleated disk-shaped cells formed in the megakaryocyte and found in the blood of all mammals. They are mainly involved in blood coagulation.	Platelets,Thrombocytes,Blood Platelet,Platelet,Platelet, Blood,Platelets, Blood,Thrombocyte
D001854	Bone Marrow Cells	Cells contained in the bone marrow including fat cells (see ADIPOCYTES); STROMAL CELLS; MEGAKARYOCYTES; and the immediate precursors of most blood cells.	Bone Marrow Cell,Cell, Bone Marrow,Cells, Bone Marrow,Marrow Cell, Bone,Marrow Cells, Bone
D002417	Cattle	Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.	Beef Cow,Bos grunniens,Bos indicus,Bos indicus Cattle,Bos taurus,Cow,Cow, Domestic,Dairy Cow,Holstein Cow,Indicine Cattle,Taurine Cattle,Taurus Cattle,Yak,Zebu,Beef Cows,Bos indicus Cattles,Cattle, Bos indicus,Cattle, Indicine,Cattle, Taurine,Cattle, Taurus,Cattles, Bos indicus,Cattles, Indicine,Cattles, Taurine,Cattles, Taurus,Cow, Beef,Cow, Dairy,Cow, Holstein,Cows,Dairy Cows,Domestic Cow,Domestic Cows,Indicine Cattles,Taurine Cattles,Taurus Cattles,Yaks,Zebus
D002454	Cell Differentiation	Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.	Differentiation, Cell,Cell Differentiations,Differentiations, Cell
D002469	Cell Separation	Techniques for separating distinct populations of cells.	Cell Isolation,Cell Segregation,Isolation, Cell,Cell Isolations,Cell Segregations,Cell Separations,Isolations, Cell,Segregation, Cell,Segregations, Cell,Separation, Cell,Separations, Cell
D002478	Cells, Cultured	Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.	Cultured Cells,Cell, Cultured,Cultured Cell