Autoregulation of B cell growth by an immunoglobulin M autoantibody
Kiely, J.M.; Braun, J.; Unanue, E.R.
Journal of Immunology 135(2): 1040-1045
1985
ISSN/ISBN: 0022-1767 PMID: 3874225 Document Number: 260657
This study documents the autoregulation of murine B cell growth by an IgM autoantibody. This autoantibody is secreted by B lymphocytes upon stimulation by polyclonal activators and is identified by its potent inhibition of B cell growth induced by these agents (endotoxin, Fc fragment or human .gamma.-globulin, Mycoplasma bovirhinis, and anti-mouse Ig). The autoantibody specifically affects B cells: there was no effect on mitogen- or antigen-induced T cell proliferation and of responses to interleukin 1, interleukin 2, or interferon. Nonspecific effects were excluded by the ineffectiveness of serum and myeloma IgM. Also, IgG-IgM immune complexes were excluded. The binding specificity of the IgM autoantibody is not yet defined but appears to be a B cell surface structure distinct from membrane Ig. The autoantibody constitutes a ubiquitous, autoregulatory influence on B cell growth, which may be an important component in physiologic and pathologic states of B cell homeostatis.