Biomaterial Database

Inhibition of human lymphocyte E-rosette formation by oxygenated sterols. 1979

R A Streuli, and J Chung, and A M Scanu, and S Yachnin

25-Hydroxycholesterol, 20 alpha-hydroxycholesterol, 7 alpha-hydroxycholesterol, and 5 alpha-hydroxy-6-ketocholestanol, when added to cultures of human lymphocytes in lipoprotein-depleted medium (LPDM) at a concentration of 2.5 x 10(-6) M, inhibit E-rosette formation with sheep red blood cells. 20 alpha-Hydroxycholesterol, 7 alpha-hydroxycholesterol, and 5 alpha-hydroxy-6-ketocholestanol are more potent inhibitors than 25-hydroxycholesterol. The inhibitory effect of 5 alpha-hydroxy-6-ketocholestanol on E-rosette formation appears after 15 min of exposure; with the other three compounds, an exposure time of 18 hr is necessary. The inhibitory effect of E-rosette formation can be abolished by addition of free cholesterol, low-density lipoprotein, or high-density lipoprotein to the LPDM or by incubation of the cells in normal AB serum, but not by the addition of mevalonic acid to the LPDM. These observations suggest that the capacity of oxygenated sterol compounds (OSC) to inhibit E-rosette formation is independent of their inhibitory effect on sterol synthesis. It is possible that OSC inhibit E-rosette formation as a consequence of their insertion into the lymphocyte membrane as cholesterol analogues.

UI	MeSH Term	Description	Entries
D007653	Ketocholesterols	Cholesterol substituted in any position by a keto moiety. The 7-keto isomer inhibits cholesterol uptake in the coronary arteries and aorta by blocking 3-hydroxy-3-methylglutaryl-CoA reductase activity.	Oxocholesterols
D007664	Ketosteroids	Steroid derivatives formed by oxidation of a methyl group on the side chain or a methylene group in the ring skeleton to form a ketone.	Oxosteroids
D008074	Lipoproteins	Lipid-protein complexes involved in the transportation and metabolism of lipids in the body. They are spherical particles consisting of a hydrophobic core of TRIGLYCERIDES and CHOLESTEROL ESTERS surrounded by a layer of hydrophilic free CHOLESTEROL; PHOSPHOLIPIDS; and APOLIPOPROTEINS. Lipoproteins are classified by their varying buoyant density and sizes.	Circulating Lipoproteins,Lipoprotein,Lipoproteins, Circulating
D008214	Lymphocytes	White blood cells formed in the body's lymphoid tissue. The nucleus is round or ovoid with coarse, irregularly clumped chromatin while the cytoplasm is typically pale blue with azurophilic (if any) granules. Most lymphocytes can be classified as either T or B (with subpopulations of each), or NATURAL KILLER CELLS.	Lymphoid Cells,Cell, Lymphoid,Cells, Lymphoid,Lymphocyte,Lymphoid Cell
D008798	Mevalonic Acid	A dihydroxy monocarboxylic acid and precursor in the biosynthetic pathway known as the mevalonate pathway, which produces terpenes and steroids that are vital for diverse cellular functions.	Mevalonate,Acid, Mevalonic
D002470	Cell Survival	The span of viability of a cell characterized by the capacity to perform certain functions such as metabolism, growth, reproduction, some form of responsiveness, and adaptability.	Cell Viability,Cell Viabilities,Survival, Cell,Viabilities, Cell,Viability, Cell
D002784	Cholesterol	The principal sterol of all higher animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils.	Epicholesterol
D003470	Culture Media	Any liquid or solid preparation made specifically for the growth, storage, or transport of microorganisms or other types of cells. The variety of media that exist allow for the culturing of specific microorganisms and cell types, such as differential media, selective media, test media, and defined media. Solid media consist of liquid media that have been solidified with an agent such as AGAR or GELATIN.	Media, Culture
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D006888	Hydroxycholesterols	Cholesterol which is substituted by a hydroxy group in any position.