Immunomodulatory effect of Tylophora indica on Con A induced lymphoproliferation.
Our preliminary studies with tylophora alkaloids had shown that they inhibit cellular immune responses like contact sensitivity to dinitro-flurobenzene and delayed hypersensitivity to sheep red blood cells, in vivo. Investigations were hence carried out to determine the cellular targets of tylophora alkaloids in in vitro systems. Con A induced proliferation of splenocytes was used as a model system to study the effect of the alkaloids on cellular immune responses. The alkaloid mixture was found to inhibit proliferation of splenocytes at higher concentrations and augment the same at lower concentrations. Both macrophages and T cells were found to be vulnerable to tylophora alkaloids. The alkaloid mixture suppressed IL-2 production in Con A stimulated splenocytes at the inhibitory or higher concentrations and enhanced production at the lower concentrations. IL-1 production by activated macrophages on the contrary was doubled in the presence of inhibitory concentrations of tylophora. These studies indicate that tylophora alkaloids have a concentration dependent biphasic effect on Con A induced mitogenesis. At lower concentrations they augment Con A induced lymphoproliferation by enhancing IL-2 production. Inhibition of proliferation at higher concentrations of the alkaloid is due to inhibition of IL-2 production and activation of macrophages, which have a cytostatic effect.
Ganguly
T
T
Cell Biology Division, Bhabha Atomic Research Centre, Mumbai, India. cenfc@nfc.ernet.in
Badheka
L P
LP
Sainis
K B
KB
D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D000470:Alkaloids / Q000494:pharmacology; D000818:Animals; D002453:Cell Cycle / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D003208:Concanavalin A / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005434:Flow Cytometry; D007375:Interleukin-1 / Q000378:metabolism; D007376:Interleukin-2 / Q000378:metabolism; D008214:Lymphocytes / Q000187:drug effects*; D008264:Macrophages / Q000378:metabolism; D019684:Magnoliopsida; D008515:Medicine, Ayurvedic; D051379:Mice; D008809:Mice, Inbred C3H; D010936:Plant Extracts / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry; D037121:Plant Lectins; D013154:Spleen / Q000166:cytology / Q000187:drug effects*; D013601:T-Lymphocytes / Q000378:metabolism
D000276:Adjuvants, Immunologic; D000470:Alkaloids; D007375:Interleukin-1; D007376:Interleukin-2; D010936:Plant Extracts; D037121:Plant Lectins; D003208:Concanavalin A