Send to

Choose Destination
Immunol Lett. 1995 Mar;45(3):195-203.

Anti-CD40 monoclonal antibody induces the proliferation of murine B cells as a B-cell mitogen through a distinct pathway from receptors for antigens or lipopolysaccharide.

Author information

Department of Immunology, School of Life Science, Faculty of Medicine, Tottori University, Yonago, Japan.


To study the activation and differentiation of murine B cells, we prepared a hybridoma secreting monoclonal antibody, LB429, which can directly induce the proliferation of murine B cells in vitro. LB429 recognizes a B cell specific surface molecule of 45 kDa. It recognizes an epitope of murine CD40 produced as a soluble fusion protein with glutathione S-transferase. LB429 stains COS-7 transfectant with murine CD40 cDNA and mature B-cell lines but does not stain pre-B cell lines. Two color staining demonstrated that the epitope recognized with LB429 appears on the surface of B220+ cells of spleen and bone marrow. LB429 can induce a strong proliferation of murine B cells from spleen in the absence of initial triggering with anti-IgM antibody or with anti-IgM antibody + IL-4. LB429 induced the cell size enlargement and the cell cycle transition of resting B cells as well as lipopolysaccharide (LPS). LB429 and LPS stimulate B cells synergistically in vitro by accumulating 44.7% of cells in S/G2/M phases of cell cycle. However, stimulation of spleen B cells with LB429 resulted in the increase of sIgM high+ sIgD(high)+ B cells, in contrast LPS showed the proliferation of both sIgM(high)+ sIgD(high)+ B cells and sIgM(low)+ sIgD(high)+ B cells. These results suggested that LB429 and LPS cause the proliferation of B cells through different stimulatory pathways. This anti-mouse CD40 antibody (LB429) is a very useful reagent to study the activation and differentiation of B cells in vitro.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center