We have previously reported that oral administration of hot water extract of Chlorella vulgaris (CVE) enhances resistance to Listeria monocytogenes through augmentation of Listeria-specific cell-mediated immunity in normal mice and mice with murine acquired immunodeficiency syndrome (MAIDS) caused by murine leukemia virus (MuLV) LP-BM5. To elucidate the mechanisms whereby CVE augments the cell-mediated immunity, we examined the expression patterns of mRNA for cytokines in normal and MAIDS mice given CVE orally after L. monocytogenes infection. The expression levels of IL-1α, IL-12, GM-CSF, MIP and TNFα genes were significantly augmented in the peritoneal adherent cells by oral administration of CVE for 2 weeks before Listeria infection. The expression levels of γIFN and IL-12 mRNA were significantly higher in the spleen after Listeria infection in CVE-treated mice than in normal mice, while the expression of IL-10 mRNA in the spleen was decreased by CVE administration. In MAIDS mice, oral administration of CVE also augmented the expression of γIFN and IL-12 mRNA in the spleen after Listeria infection, while it rather reduced the expression of IL-10 mRNA. These results suggest that CVE may preferentially augment Th1 responses against Listeria via activation of macrophages to produce IL-12 and enhance host defense against Listeria infection both in normal and MAIDS mice.
All Science Journal Classification (ASJC) codes