Immunomodulating polysaccharides from the lichen Thamnolia vermicularis var. subuliformis.
Three heteroglycans Ths-4, Ths-5 and thamnolan and a beta-glucan, Ths-2, isolated from the lichen Thamnolia vermicularis var. subuliformis were tested for in vitro immunomodulating activities and shown to have various influences on the immune system. All the polysaccharides except Ths-4 caused a stimulation of rat spleen cell proliferation. In contrast, Ths-4 caused cell death early in the culture, probably due to over-stimulation. Moreover, the galactofuranomannans, Ths-4, Ths-5 and the beta-glucan Ths-2, induced rat spleen cells to secrete IL-10 significantly above background levels. In addition, Ths-4 and Ths-5 stimulated significant TNF-alpha secretion by rat peritoneal macrophages. The galactofuranomannans Ths-4 and Ths-5 have similar structures apart from the molecular weight. Thus, it may be concluded that the molecular size might influence the potency but not the pattern of activity for Ths-4 and Ths-5. The galactofuranorhamnan thamnolan had less mitogenic effect than Ths-5 and Ths-2 and neither induced IL-10 secretion by rat spleen cells nor TNF-alpha secretion by peritoneal macrophages to significant levels. This shows that thamnolan with its unusual galactofuranorhamnan structure differs from the other Thamnolia polysaccharides in its immunomodulatory activity.
Omarsdottir
Sesselja
S
University of Iceland, Hagi, Hofsvallagata 53, IS-107 Reykjavik, Iceland.
Freysdottir
Jona
J
Olafsdottir
Elin Soffia
ES
D000818:Animals; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured / Q000187:drug effects / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D007107:Immune System / Q000187:drug effects*; D007155:Immunologic Factors / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D016753:Interleukin-10 / Q000096:biosynthesis; D008011:Lichens; D017737:Macrophages, Peritoneal / Q000187:drug effects / Q000378:metabolism; D008517:Phytotherapy; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D011134:Polysaccharides / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D051381:Rats; D013154:Spleen / Q000166:cytology / Q000187:drug effects; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
D007155:Immunologic Factors; D010936:Plant Extracts; D011134:Polysaccharides; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10