Novel sulfated polysaccharide derived from red-tide microalga Gyrodinium impudicum strain KG03 with immunostimulating activity in vivo.
The high-sulfate-containing exopolysaccharide p-KG03 is produced by the red-tide microalga Gyrodinium impudicum strain KG03. The immunostimulatory effects of this sulfated exopolysaccharide were investigated by isolating peritoneal macrophages from mice 10 or 20 days after they had received a single dose of p-KG03 (100 or 200 mg/kg body weight). The cytotoxicity of the isolated macrophages for B16 tumor cells was tested, as B16 tumor cells are sensitive to tumor necrosis factor alpha (TNF-alpha) and nitric oxide. The activities of natural killer cells from the p-KG03-treated mice against YAC-1 mouse lymphoma cells were also tested. The nonspecific immune functions mediated by natural killer cells and macrophages were increased by treatment with p-KG03 in vivo. These results suggest that p-KG03 has immunostimulatory effects and enhances the tumoricidal activities of macrophages and NK cells in vivo. In addition, p-KG03 treatment increased the plaque-forming cell response to sheep red blood cells, as well as the levels of IgM and IgG Exposure to p-KG03 also increased the production by macrophages of cytokines, such as interleukins -1beta and -6, and TNF-alpha. This is the first report of a marine microalgal sulfated polysaccharide having immunostimulatory activities. The p-KG03 polysaccharide may be useful for the development of biotechnological and pharmaceutical products that incorporate bioactive marine exopolysaccharides.
Yim
Joung Han
JH
Korea Polar Research Institute, KORDI, Ansan, P.O. Box 29, Seoul, 425-600, Republic of Korea.
Son
Eunwha
E
Pyo
Suhkneung
S
Lee
Hong Kum
HK
D000818:Animals; D045744:Cell Line, Tumor; D016207:Cytokines / Q000378:metabolism; D004141:Dinoflagellida / Q000737:chemistry*; D004797:Enzyme-Linked Immunosorbent Assay; D006861:Hydrogen Peroxide / Q000378:metabolism; D007114:Immunization; D007074:Immunoglobulin G / Q000378:metabolism; D007075:Immunoglobulin M / Q000378:metabolism; D007694:Killer Cells, Natural / Q000187:drug effects / Q000276:immunology; D008264:Macrophages / Q000187:drug effects / Q000276:immunology; D051379:Mice; D011134:Polysaccharides / Q000737:chemistry / Q000276:immunology* / Q000494:pharmacology; D013463:Sulfuric Acid Esters / Q000737:chemistry / Q000276:immunology* / Q000494:pharmacology
D016207:Cytokines; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D011134:Polysaccharides; D013463:Sulfuric Acid Esters; D006861:Hydrogen Peroxide