irradiated β-glucan enhances immune response to bacterial infection through cd4 and cd8 t-lymphocytes

background: &beta-glucans; are glucose polymers with a variety of stimulatory effects on the immune system. the objective of this study was to evaluate the immune-enhancing activities of low molecular weight gamma irradiated &beta-glucan; (i&beta-g;) extracted from pleurotus ostreatus in response to pseudomonas aeruginosa infection in rats. materials and methods: &beta-glucan; (&beta-g;) powder was exposed to 50 kgy of gamma radiation. for experimental study, healthy male rats were divided in six groups. group i: did not receive any treatment. group 2: infected group was injected once with p. aeruginosa. group 3: were orally administrated with &beta-g; for 15 days at a dose of 65 mg/kg body weight/day. group 4: were orally administrated with i&beta-g; for 15 days at a dose of 65 mg/kg body weight/day. group 5: rats were treated with &beta-g; and injected once with p. aeruginosa. group 6: rats were treated with i&beta-g; and injected once with p. aeruginosa. rats were sacrificed 24 h post bacterial infection. results: &beta-g; and i&beta-g; were characterized using ftir spectra and sem, showed breakdown of the glycosidic bonds with deformation and splitting of &beta-g; molecule. oral ingestion of &beta-g; markedly enhanced the production of lymphocytes and leucocytes and cd8 compared to that of i&beta-g;, although i&beta-g; was more effective in stimulating cd4 count compared to that of &beta-g; and ameliorated cd4/cd8 ratio. i&beta-g; enhanced gpx and cat activity, elevated zinc concentration in the blood compared to that of &beta-g;, although both i&beta-g; and &beta-g; elevated gsh and caused no effect on mda level in post infected groups. conclusion: in conclusion i&beta-g; improves antioxidant state and enhances immune system in particular cd4 count against bacterial infections which is an important marker of immune system.