Premium
Rigid plasma‐membrane‐derived vesicles, enriched in tumour‐associated surface antigens (MLr), occurring in the ascites fluid of a murine leukaemia (GRSL)
Author(s) -
van Blitterswijk W. J.,
Emmelot P.,
Hilkmann H. A. M.,
Hilgers J.,
Feltkamp C. A.
Publication year - 1979
Publication title -
international journal of cancer
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.475
H-Index - 234
eISSN - 1097-0215
pISSN - 0020-7136
DOI - 10.1002/ijc.2910230112
Subject(s) - vesicle , sphingomyelin , membrane , biology , budding , microbiology and biotechnology , cell membrane , biochemistry , cell , glycolipid , chemistry , biophysics
Extracellular membraneous vesicles of GRSL leukaemia cells were isolated from the ascites fluid bathing the cells in vivo, and from cell washes. Mammary tumour virus‐induced antigens (MLr) expressed on the surface of the cells are enriched on these vesicles as compared to plasma membranes isolated from the cell homogenate. The lipid fluidity of the vesicles is much smaller than that of the plasma membranes, and the content of the pertinent lipid parameters, cholesterol and sphingomyelin, are accordingly greatly increased. The extracellular vesicles which are also enriched in sialic acid and 5‐nucleotidase are apparently derived from the plasma membrane, probably at least partly by exfoliation of selected parts or domains of the surface of living cells. An analogy between this shedding of vesicles, the formation of endocytotic vesicles and the budding of viruses is noted; all these processes select or assemble rigid lipid domains of the cell membrane. The possible participation of surface microvilli and sub‐lethal autolysis in the process of shedding is discussed.