Effect(s) of lipopolysaccharide on lectin-induced T-cell activation.
The present study focuses on the effect of lipopolysaccharide (LPS) on the cellular events leading to T-cell activation by concanavalin A (Con A). Interleukin 2 (Il-2) production is much reduced in Con A-stimulated cultures of spleen cells derived from LPS-treated mice. This depressed Il-2 synthesis is not related to the eventual activity of LPS-activated suppressive B cells. Rather, it reflects an ineffective collaboration between adherent cells and T lymphocytes. The low level of Il-2 produced by LPS-sensitized spleen cells is sufficient for lectin-induced T-cell proliferation. Moreover, acquisition of responsiveness to Il-2 is unaltered by LPS. No strict correlation was found between the deficiency in Il-2 production and the inability of LPS-sensitized spleen cells to generate a thymus-dependent response. Less time (5 hr) is needed for LPS to exert its inhibitory effect on an anti-sheep red blood cell response than on Il-2 synthesis (at least 24 hr). Results are discussed in terms of cellular interactions implicated in a polyclonal T-cell response and with regard to the contribution of Il-2 to the LPS-induced immune unresponsiveness.
D000818:Animals; D002450:Cell Communication / Q000187:drug effects; D002478:Cells, Cultured; D003208:Concanavalin A / Q000494:pharmacology; D005260:Female; D007376:Interleukin-2 / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology; D008213:Lymphocyte Activation; D008264:Macrophages / Q000276:immunology; D051379:Mice; D011971:Receptors, Immunologic / Q000378:metabolism; D015375:Receptors, Interleukin-2; D013154:Spleen / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*; D013997:Time Factors
D007376:Interleukin-2; D008070:Lipopolysaccharides; D011971:Receptors, Immunologic; D015375:Receptors, Interleukin-2; D003208:Concanavalin A