Cognate interactions between helper T cells and B cells. VI. TGF-beta inhibits B cell activation and

W C Bartlett1, A Purchio, H P Fell

  • 1Department of Microbiology, Dartmouth Medical School, Hanover, NH 03755.

Lymphokine and Cytokine Research
|June 1, 1991
PubMed

TGF-beta is a 25-kDa homodimeric protein that has been shown to have multiple roles in the regulation of lymphocyte activation. Previous studies have shown that TGF-beta is an inhibitor of numerous T and B lymphocyte activities. This study shows that TGF-beta is able to inhibit Th- and mitogen-induced murine B cell proliferation, as well as mitogen-induced B cell cycle entry and immunoglobulin secretion. Acridine orange analysis established that TGF-beta inhibits the LPS-induced B cell transition from G0 to G1A phase of the cell cycle. Evaluation of the effects of TGF-beta on the interactions between Th and B cells showed that TGF-beta inhibited antigen-specific Th-B cell physical interactions. Flow cytometric data showed that the ability of TGF-beta to interfere with the formation of Th-B cell conjugates was not due to decreased expression of IgD, IgM, class I, class II, LFA-1, or ICAM1 by the B cell. Taken together, these data establish that TGF-beta is able to act at multiple sites within the immune system.

Related Concept Videos

TGF - β Signaling Pathway01:16

TGF - β Signaling Pathway

The TGF-β signaling pathway regulates cell growth, differentiation, adhesion, motility, and development. TGF-β ligands that induce TGF-β signaling are synthesized in their latent form. Several proteases or cell surface receptors such as integrins act upon the latent form, releasing the active ligand. There are three types of mammalian TGF-βs: (TGF-β1, TGF-β2, and TGF-β3) that bind as homodimers or heterodimers to TGF-β receptors. The TGF-β receptors are of three kinds RI, RII, and RIII. The RI...
Special Features of Adaptive Immunity01:20

Special Features of Adaptive Immunity

The adaptive immune system, a crucial component of the overall immune response, offers a highly specialized defense against pathogens. It involves specific cell types and features, enabling it to combat infections effectively and efficiently.
The primary cell types involved in adaptive immunity are T cells and B cells. Each type has a unique role in defending the body against pathogens. T cells are responsible for cell-mediated immunity. They identify and eliminate infected cells directly,...
T Cell Activation and Clonal Selection01:22

T Cell Activation and Clonal Selection

T cells are integral to our adaptive immune system, recognizing and effectively responding to foreign antigens. T cell activation and clonal selection are pivotal in orchestrating this immune response. This article elucidates these mechanisms, detailing the roles of cluster of differentiation (CD) markers, major histocompatibility complex (MHC) molecules, costimulatory signals, and the process of clonal selection.
Naive T cells that have not yet encountered an antigen express two primary CD...
T Cell Types and Functions01:24

T Cell Types and Functions

When T cells with CD4 markers are activated, they give rise to two types of effector cells: helper T cells and regulatory T cells. Meanwhile, T cells with CD8 markers differentiate into effector cytotoxic T cells. The differentiation of CD4 T cells into helper T cell subsets, such as Th1, Th2, and Th17 cells, is dependent on the antigen type, antigen-presenting cell, and regulatory cytokines.
Th1 cells stimulate dendritic cells to express necessary co-stimulatory molecules on their surfaces for...
B Cell Activation and Differentiation01:24

B Cell Activation and Differentiation

The adaptive immune response, a sophisticated defense mechanism, relies on the activation and differentiation of B lymphocytes, or B cells. These processes enable our bodies to mount a tailored response against specific pathogens such as bacteria, free virus particles, toxins, and parasites.
When naive B cells encounter a specific antigen that can bind to the B cell receptor (BCR) on their surface, they undergo sensitization to respond to the antigen's presence. Sensitization begins with...
Defense Against Bacterial Pathogens01:31

Defense Against Bacterial Pathogens

The human immune system is a complex network of cells, tissues, and organs that work together to defend the body against bacterial infections. It consists of various immune cells, each playing a specific role in the defense mechanism.
Phagocytes
Phagocytes are the frontline soldiers of the immune system. They include neutrophils and macrophages. Neutrophils are the most abundant type of white blood cell and are quickly mobilized to the site of infection. Macrophages are larger cells that patrol...