The polysaccharides of Ganoderma lucidum (Reishi) possess immunomodulation activities; however, their mode of molecular action in regulating each cellular subset in the immune system is still not clear. Here, we investigate the function of the main polysaccharide fraction of Reishi (Reishi-F3) in B lymphocyte activation/differentiation. We find that Reishi-F3 causes mouse splenic B cell activation and differentiation to IgM-secreting plasma cells, and the process depends on Reishi-F3-mediated induction of Blimp-1, a master regulator capable of triggering the changes of a cascade of gene expression during plasmacytic differentiation. In human peripheral B lymphocytes, although Reishi-F3 fails to induce their activation, it is able to enhance antibody secretion, which is associated with Blimp-1 mRNA induction. The function of Reishi-F3 depends on the Toll-like receptors TLR4/TLR2 as neutralizing antibodies against TLR4/TLR2 block Reishi-F3-mediated induction of Blimp-1 mRNA and Ig secretion. We have shown that interaction of Reishi-F3 with TLR4/TLR2 followed by signaling through p38 MAPK is involved in the induction of Blimp-1 mRNA, whereas signaling through ERK, p38 MAPK, JNK, and IKK complex is involved in Reishi-F3-mediated Ig secretion. Furthermore, the differential mechanism of Reishi-F3 in mouse and human B cell activation is probably due to the presence of Blimp-1 regulatory site in human CD86 promoter. These results establish the signaling and molecular mechanisms of Reishi-F3 on promoting antibody secretion.

Download full-text PDF

Source
http://dx.doi.org/10.1074/jbc.M601106200DOI Listing

Publication Analysis

Top Keywords

induction blimp-1
12
blimp-1 mrna
12
reishi-f3 mouse
8
cell activation
8
reishi-f3-mediated induction
8
antibody secretion
8
p38 mapk
8
reishi-f3
7
blimp-1
6
induction
5

Similar Publications

It's the little things in life: Lymph node microniches drive T2 formation in allergic asthma.

Sci Immunol

December 2024

Department of Medicine, Division of Allergy and Immunology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA.

Article Synopsis
  • The study investigates how IL-2 microniches in lymph nodes influence the development of T2 cells, which play a role in immune responses.
  • It highlights the importance of Blimp-1, a protein that regulates immune cell function, in this developmental process.
  • Additionally, the research points out that IL-10, an anti-inflammatory cytokine, contributes to a positive feedback loop, enhancing T2 cell development.
View Article and Find Full Text PDF

ICAM-1 mediated cell-cell adhesion exerts dual roles on human B cell differentiation and IgG production.

iScience

December 2023

Shanghai Institute of Immunology, Department of Immunology and Microbiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.

Intercellular adhesion molecule 1 (ICAM-1) plays prominent roles in mediating cell-cell adhesion which also facilitates B cell activation and differentiation with the help from CD4 T cells. Here, we have reported a unique phenomenon that increased ICAM-1 on purified human CD4 T cells upon anti-CD3/CD28 stimulation enhanced CD4 T-B cell adhesion whereas induced less B cell differentiation and IgG production. This was largely due to increased PD-1 expression on CD19 B cells after coculturing with hyperactivated CD4 T cells.

View Article and Find Full Text PDF

Background: Vitamin D (VitD) is known to have immunomodulatory functions, and VitD deficiency is associated with more severe asthma.

Objective: We aimed to assess the immunoregulatory effects of VitD food supplementation on asthma manifestation, with particular focus on T cells and type 2 innate lymphoid cells.

Methods: Preschool children and adult asthmatic cohorts were analyzed in the context of VitD supplementation and serum levels.

View Article and Find Full Text PDF

Phytogalactolipids activate humoral immunity against colorectal cancer.

J Exp Clin Cancer Res

April 2023

Agricultural Biotechnology Research Center, Academia Sinica, No. 128, Sec. 2, Academia Road, Nankang, Taipei, 11529, Taiwan.

Background: Colorectal cancer (CRC) is the third most lethal cancer in the world, and its incidence is steadily rising. In this study, we investigated the induction of humoral immunity by a phytogalactolipid enriched fraction (CRA) derived from the medicinal plant Crassocephalum rabens (Benth.) S.

View Article and Find Full Text PDF

Control of intracellular parasites responsible for malaria requires host IFN-γ+T-bet+CD4+ T cells (Th1 cells) with IL-10 produced by Th1 cells to mitigate the pathology induced by this inflammatory response. However, these IL-10-producing Th1 (induced type I regulatory [Tr1]) cells can also promote parasite persistence or impair immunity to reinfection or vaccination. Here, we identified molecular and phenotypic signatures that distinguished IL-10-Th1 cells from IL-10+Tr1 cells in Plasmodium falciparum-infected people who participated in controlled human malaria infection studies, as well as C57BL/6 mice with experimental malaria caused by P.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!