Effects of human anti-IL-1 alpha autoantibodies on receptor binding and biological activities of IL-1

Cytokine. 1992 Mar;4(2):125-33. doi: 10.1016/1043-4666(92)90047-u.


Immunoglobulin G (IgG) antibodies to interleukin 1 alpha (IL-1 alpha) are frequently found in the sera of healthy human individuals. The effects of these autoantibodies on receptor binding and biological activities of human IL-1 were tested. Using the murine T-lymphocyte line NOB-1, human thyrocytes and human foreskin fibroblasts, the antibodies competitively inhibited the biological activity of human recombinant IL-1 alpha (rIL-1 alpha). The degree of inhibition correlated with 125I-rIL-1 alpha binding to IgG in different immunoglobulin preparations and in individual sera. These antibodies also neutralized the IL-1 activity of isolated membrane fragments and lysates of human blood monocytes activated by lipopolysaccharide. In contrast, the supernatant IL-1 activity was not affected. Stronger inhibition of biological activity and cell binding of 125I-rIL-1 alpha was obtained with NOB-1 cells than with human thyrocytes. The antibodies failed to interfere with the biological activity of rIL-1 beta. It is concluded that IgG autoantibodies of IL-1 alpha in the sera of healthy humans selectively inhibit the biological activity of the soluble and membrane-associated forms of IL-1 alpha in vitro, and that the degree of biological inhibition afforded by these antibodies depends upon the target cell.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Autoantibodies / blood
  • Autoantibodies / immunology*
  • Cells, Cultured
  • Chromatography, Affinity
  • Fibroblasts / chemistry
  • Humans
  • Immunoassay
  • Interleukin-1 / immunology*
  • Interleukin-1 / metabolism
  • Interleukin-1 / pharmacology*
  • Iodine Radioisotopes
  • Lymphoid Tissue / chemistry
  • Lymphoid Tissue / cytology
  • Mice
  • Receptors, Immunologic / metabolism*
  • Receptors, Interleukin-1
  • Thyroid Gland / chemistry
  • Thyroid Gland / cytology


  • Autoantibodies
  • Interleukin-1
  • Iodine Radioisotopes
  • Receptors, Immunologic
  • Receptors, Interleukin-1