title: The in vivo and in vitro effects of caffeine on rat immune cells activities: B, T and NK cells.
abstract: The effect of caffeine (naturally occurring plant methylxanthine) on immunological cell activities in Sprague-Dawley rat both in vivo and in vitro was studied. A cytotoxic assay was done to study natural killer (NK) cells and a proliferation assay was performed for T and B cell activities. Three different doses of caffeine i.e., 2, 6 and 18 mg/kg/day were administered chronically to Sprague-Dawley rats to assess the effects in vivo. Both NK cell cytotoxicity and B cell proliferative response to pokeweed mitogen (PWM) showed significant decreases (P less than 0.05) in rats treated with 6 mg/kg/day, whereas the T cell proliferative response to phytohemagglutinin-P (PHA-P) was significantly increased (P less than 0.05) in the rats treated with 18 mg/kg/day. In vitro, caffeine significantly decreases (P less than 0.05) B and T cell proliferative responses to PWM and PHA-P at added caffeine concentrations of 10, 20 and 40 micrograms/ml. However, no effect was observed on NK cells activity. Furthermore, in vitro, a broader dose range of caffeine (1, 10, 100 and 1,000 micrograms/ml) exhibited dose-dependent inhibition of both B and T cell proliferative responses.
authors.affiliation: Department of Microbiology, Faculty of Science, Mahidol University, Bangkok, Thailand.
authors.forename: D
authors.initials: D
authors.lastname: Kantamala
authors.forename: M
authors.initials: M
authors.lastname: Vongsakul
authors.forename: J
authors.initials: J
authors.lastname: Satayavivad
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology*; D002110:Caffeine / Q000008:administration & dosage / Q000494:pharmacology*; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D003602:Cytotoxicity, Immunologic; D066298:In Vitro Techniques; D007694:Killer Cells, Natural / Q000276:immunology*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D002110:Caffeine