ABSTRACT
This study investigated whether elevated host immune capacity can inhibit T. gondii infection. For this purpose, we used silk protein extracted from Bombyx mori cocoons as a natural supplement to augment immune capacity. After silk protein administration to BALB/c mice for 6 weeks, ratios of T lymphocytes (CD4+ and CD8+ T-cells) and splenocyte proliferative capacities in response to Con A or T. gondii lysate antigen (TLA) were increased. Of various cytokines, which regulate immune systems, Th1 cytokines, such as IFN-gamma, IL-2, and IL-12, were obviously increased in splenocyte primary cell cultures. Furthermore, the survival of T. gondii (RH strain)-infected mice increased from 2 days to 5 or more days. In a state of immunosuppression induced by methylprednisolone acetate, silk protein-administered mice were resistant to reduction in T-lymphocyte (CD4+ and CD8+ T-cells) numbers and the splenocyte proliferative capacity induced by Con A or TLA with a statistical significance. Taken together, our results suggest that silk protein augments immune capacity in mice and the increased cellular immunity by silk protein administration increases host protection against acute T. gondii infection.
Subject(s)
Animals , Male , Mice , Bombyx/chemistry , CD4-CD8 Ratio , Cell Proliferation , Cells, Cultured , Cytokines/metabolism , Insect Proteins/immunology , Leukocytes, Mononuclear/immunology , Mice, Inbred BALB C , Silk/immunology , Spleen/immunology , Survival Analysis , Toxoplasma/immunology , Toxoplasmosis, Animal/immunologyABSTRACT
The inhibitory effect of rice(Oryza sartiva L., illpumbyeo) against mutagenicity induced by tryptophan pyrolysates were investigated using Salmonella typhimurium reversion assay. Both methanol extracts of obtained from brown and white rice were found to possess strong activites of inhibiting the mutagenicities of 3-amino-1,4-dimethyl-5H-pyriod[4,3-b]indol(Trp-P-1) and 3-amino-1-methyl-5H-pyrido[4,3-b]indol(Trp-P-2) on Salmonella typhimurium reversion assay. As the concentration of methanol extract increased, inhibitory effect on mutagenicity increased but reached at steady state as inhibition rate of 90% when the concentration was above 10mg/plate. There was no significant difference(p>0.05) in inhibitory effect of methanol extracts between brown and white rice against tryptophan pyrolysates.