Effects of a pectic polysaccharide from a medicinal herb, the roots of Bupleurum falcatum L. on interleukin 6 production of murine B cells and B cell lines.
The effect of T-cell-independent B cell mitogen, a pectic polysaccharide, bupleuran 2IIc, from a medicinal herb, the roots of Bupleurum falcatum L. on interleukin 6 (IL-6) production of murine B cells and B cell lines was investigated in order to clarify the mechanism of enhanced immunoglobulin (Ig) secretion from B cells. Bupleuran 2IIc enhanced IgM secretion from highly purified murine normal B cells. When normal B cells from murine spleen were cultured with bupleuran 2IIc in the presence of anti-IL-6 neutralizing antibody, the enhanced IgM secretion by bupleuran 2IIc was reduced. When B cells were stimulated with bupleuran 2IIc, their IL-6 secretion and the transcription of IL-6 mRNA were enhanced. The enhanced IL-6 secretion by bupleuran 2IIc was also observed in B cell line, Y16 cell. When bupleuran 2IIc was digested with endo-alpha-(1-->4)-D-polygalacturonase, the resulting enzyme resistant carbohydrate portion, "ramified" region (PG-1) composed of rhamnogalacturonan core containing neutral sugar side chains showed potent IL-6 secretion-enhancing activity. These results suggest that the "ramified" region of bupleuran 2IIc stimulates the secretion of IL-6 as the active site, and the resulting IL-6 may partially contribute the enhancement of IgM secretion as an autocrine and/or paracrine mechanism.
Guo
Y
Y
Oriental Medicine Research Center, The Kitasato Institute, 5-9-1, Shirokane, Minato-ku, 108-8642, Tokyo, Japan.
Matsumoto
T
T
Kikuchi
Y
Y
Ikejima
T
T
Wang
B
B
Yamada
H
H
D000276:Adjuvants, Immunologic / Q000737:chemistry / Q000494:pharmacology*; D000818:Animals; D001402:B-Lymphocytes / Q000187:drug effects* / Q000378:metabolism; D029972:Bupleurum; D002460:Cell Line; D004365:Drugs, Chinese Herbal / Q000737:chemistry / Q000494:pharmacology*; D005260:Female; D007106:Immune Sera / Q000494:pharmacology; D007075:Immunoglobulin M / Q000096:biosynthesis; D015850:Interleukin-6 / Q000096:biosynthesis* / Q000276:immunology / Q000378:metabolism; D051379:Mice; D008809:Mice, Inbred C3H; D010368:Pectins / Q000737:chemistry / Q000494:pharmacology*; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D018517:Plant Roots / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*; D013329:Structure-Activity Relationship; D014407:Tumor Cells, Cultured
D000276:Adjuvants, Immunologic; C051274:Bupleurum root extract; D004365:Drugs, Chinese Herbal; D007106:Immune Sera; D007075:Immunoglobulin M; D015850:Interleukin-6; D010936:Plant Extracts; C073829:Bupleuran 2IIc; D010368:Pectins