Polysaccharide isolated from the radix of Platycodon grandiflorum selectively activates B cells and macrophages but not T cells

Citation
Sb. Han et al., Polysaccharide isolated from the radix of Platycodon grandiflorum selectively activates B cells and macrophages but not T cells, INT IMMUNO, 1(11), 2001, pp. 1969-1978
Citations number
33
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Immunology
Journal title
INTERNATIONAL IMMUNOPHARMACOLOGY
ISSN journal
1567-5769 → ACNP
Volume
1
Issue
11
Year of publication
2001
Pages
1969 - 1978
Database
ISI
SICI code
1567-5769(200110)1:11<1969:PIFTRO>2.0.ZU;2-9
Abstract
Many polysaccharides isolated from plants are considered to be biological r esponse modifiers and have been shown to enhance various immune responses i n vivo and in vitro. Here, we demonstrate that polysaccharide isolated from the radix of Platycodon grandiflorum (PG) has a unique mode of immunostimu lation with regard to its cell-type specificity. PG was found to markedly i ncrease polyclonal IgM antibody production and the proliferation of B cells , and to activate iNOS transcription and NO production in macrophages. More over, the intraperitoneal administration of PG in mice resulted in increase d IgM antibody production in B cells, which were immunized by using T-depen dent antigen sheep red blood cells (sRBCs). However, PG did not affect the proliferation of T cells, the IL-2 expression of Th1 cells, or the IL-4 exp ression of Th2 cells. Although PG and lipopolysaccharide (LPS) had a simila r mode of action in B cells and macrophages, they were differentiated by th e fact that PO-induced cellular activation was not inhibited by polymyxin B , a specific inhibitor of LPS. Anti-CD19 or anti-CD79b antibody blocked B c ell proliferation and anti-CD14 or anti-CD11b antibody decreased macrophage NO production, indicating the possible cellular binding sites of PG. Our r esults demonstrate that PG is a specific activator of B cells and macrophag es but not of T cells, and suggest that PG is quite distinct from other wel l-known immuno stimulants, such as lentinan and schizophyllan, which mainly act upon macrophages and T cells. (C) 2001 Elsevier Science B.V. All right s reserved.