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

Immunopharmacology. 2000 Sep;49(3):307-16. doi: 10.1016/s0162-3109(00)00245-9.

Abstract

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adjuvants, Immunologic / chemistry
  • Adjuvants, Immunologic / pharmacology*
  • Animals
  • B-Lymphocytes / drug effects*
  • B-Lymphocytes / metabolism
  • Bupleurum
  • Cell Line
  • Drugs, Chinese Herbal / chemistry
  • Drugs, Chinese Herbal / pharmacology*
  • Female
  • Immune Sera / pharmacology
  • Immunoglobulin M / biosynthesis
  • Interleukin-6 / biosynthesis*
  • Interleukin-6 / immunology
  • Interleukin-6 / metabolism
  • Mice
  • Mice, Inbred C3H
  • Pectins / chemistry
  • Pectins / pharmacology*
  • Plant Extracts / chemistry
  • Plant Extracts / pharmacology*
  • Plant Roots / chemistry
  • Plants, Medicinal / chemistry*
  • Structure-Activity Relationship
  • Tumor Cells, Cultured

Substances

  • Adjuvants, Immunologic
  • Bupleurum root extract
  • Drugs, Chinese Herbal
  • Immune Sera
  • Immunoglobulin M
  • Interleukin-6
  • Plant Extracts
  • Bupleuran 2IIc
  • Pectins