Regulation of resting and cycling human B lymphocytes via surface IgM and the accessory molecules interleukin-4, CD23 and CD40

Immunology. 1989 Dec;68(4):526-31.

Abstract

Experiments were designed in order to compare directly the ability of a new and potent monoclonal anti-mu chain antibody to initiate or maintain stimulation in resting and cycling B lymphocytes, respectively. Resting B cells could be stimulated by soluble anti-mu only in the presence of additional signals; these could be supplied by a high dose of phorbol ester or a combination of interleukin-4 (IL-4) and the CD40 antibody, G28-5. Immobilization of anti-mu not only increased the magnitude of the resting B-cell response but also diminished the co-factor requirements. The 'background' stimulation obtained when using a high concentration of immobilized anti-mu was unexpectedly reduced in the presence of IL-4 alone. The duration, but not the magnitude, of the IL-4 signal required for promoting optimal responses varied with the co-stimulation applied. Importantly, the threshold concentrations of soluble anti-mu needed to trigger the resting B cells were reduced upon the addition of each co-stimulant. With actively cycling B cells, both soluble and immobilized anti-mu were now capable of sustaining stimulation which could be prolonged on the addition of IL-4 and/or G28-5. In both resting and cycling populations, a strong correlation was noted between the magnitude of stimulation elicited when IL-4 was present and the release of the soluble CD23 molecule. Moreover, IL-4-promoted, but not other, stimulations could be augmented up to 10-fold by the inclusion of the CD23 antibody MHM6. Both the resting and cycling B-cell populations were found to secrete IgM in direct response to IL-4 and G28-5; this factor-driven production of IgM was differentially modulated by soluble and immobilized anti-mu in the two populations.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antibodies, Monoclonal / immunology
  • Antigens, CD / physiology*
  • Antigens, Differentiation, B-Lymphocyte / physiology*
  • B-Lymphocytes / immunology*
  • CD40 Antigens
  • Cells, Cultured
  • Humans
  • Immunoglobulin E
  • Immunoglobulin M / physiology*
  • Interleukin-4 / physiology*
  • Lymphocyte Activation / immunology
  • Receptors, Antigen, B-Cell / physiology*
  • Receptors, Fc / physiology*
  • Receptors, IgE

Substances

  • Antibodies, Monoclonal
  • Antigens, CD
  • Antigens, Differentiation, B-Lymphocyte
  • CD40 Antigens
  • Immunoglobulin M
  • Receptors, Antigen, B-Cell
  • Receptors, Fc
  • Receptors, IgE
  • Interleukin-4
  • Immunoglobulin E