| 释义 |
antigen|ˈæntɪdʒɛn|
[a. G. antigen, ad. F. antigène adj. (L. Deutsch 1899, in Ann. de l'Inst. Pasteur XIII. 704), f. antibody + -gen.]
A foreign substance which, when introduced into a living organism, stimulates the production of an antibody.
1908Park & Bolduan in Nuttall & Graham-Smith Bacteriol. of Diphtheria 628, v. Pirquet and Schick attribute the immediate or hastened reaction and indeed the serum disease as a whole to an interaction between the antigen and the antibody. 1911Jrnl. Chem. Soc. C. ii. 812 When an optimum dose of antigen (goat's or rat's blood) is injected intravenously into a dog. 1955Sci. News Let. 16 Apr. 253/1 The test reaction is based on the body's ability to react to and destroy bacteria and foreign protein invaders. These foreign agents are called antigens, while the body's own destructive agents are referred to as antibodies. 1959Chambers's Encycl. VII. 398/1 Most antigens are proteins or contain substantial amounts of protein, and they have a high molecular weight.
Hence antiˈgenic a., of the nature of an antigen, antiˈgenically adv. So ˌantigeˈnicity, the condition or property of being antigenic.
1913Arch. Internal Med. XI. 85 The ‘antigenic’ function of all the extracts resides solely in the lipoid fraction. 1916Olitsky & Bernstein in Jrnl. Infectious Diseases XIX. 259 We have shown that organisms grown on serum media incorporate..those serum elements which possess serum antigenic properties. 1946Nature 27 July 120/1 The hæmagglutinins are complexes of a phospholipid (probably lecithin) with an antigenically specific virus constituent. Ibid. 17 Aug. 239/1 The loss in antigenicity during preparation of the toxoid (measured by flocculation) was about half that usually found.
▸ antigen-presenting cell n. Immunol. any cell that assists in the production of immune responses by presenting antigen (see present v.); esp. any of several types of cell with monocytic lineage that present antigen in association with class II MHC molecules, to helper T lymphocytes.
1975Proc. National Acad. Sci. U.S.A. 72 5098/2 It may therefore be that..interaction between sensitized lymphocytes and *antigen-presenting cells leads to the generation of suppressive influences which prevent the DTH response. 1985Sci. Amer. June 40/1 They set out to show that Langerhans cells synthesize interleukin-1 (IL-1), a factor known to be secreted by other antigen-presenting cells, the macrophages. 2000Brit. Med. Jrnl. (Electronic ed.) 9 Dec. 1430 [Statins] do this by blocking the ability of interferon gamma, a cytokine, which activates antigen presenting cells, to express MHC-II on their surface. |