An activated murine B cell lymphoma line (A-20) produces a factor-like activity which is functionally related to human natural killer cell stimulatory factor

Eur J Immunol. 1992 Dec;22(12):3173-8. doi: 10.1002/eji.1830221222.


In the present article we show that supernatants derived from lipopolysaccharide (LPS) or phorbol 12-myristate 13-acetate (PMA)-stimulated A-20 B cell lymphoma are able to induce polyclonal immunoglobulin (Ig) secretion by normal B cells in a T-cell-dependent manner. This activity could be blocked by neutralizing monoclonal antibodies against interferon-gamma, but not by monoclonal antibodies against interleukin (IL)-2, IL-4, IL-5, IL-6, IL-10 and granulocyte macrophage colony-stimulating factor (GM-CSF) or even a polyclonal antibody against tumor necrosis factor (TNF)-alpha. Furthermore, A-20 supernatants induced the production of measurable amounts of interferon-gamma by normal murine spleen cells and activates natural killer (NK) cells. Fractionation of factor-rich supernatants on a Sephacryl S-200 column revealed that the factor activity is located in the fractions corresponding to a molecular mass of 160-150 kDa and 80-70 kDa. The biological activities found in the A-20 supernatant are very similar to the ones described for the recently cloned human IL-12/NK cell stimulatory factor. These results suggest the existence of a murine analogous factor for the human IL-12 produced by A-20 B cell lymphoma.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Immunoglobulins / biosynthesis
  • Interferon-gamma / biosynthesis*
  • Interleukin-12
  • Interleukins / physiology*
  • Killer Cells, Natural / immunology*
  • Lipopolysaccharides
  • Lymphocyte Activation
  • Lymphoma, B-Cell / metabolism*
  • Mice
  • Mice, Inbred BALB C
  • Mice, Inbred C3H
  • Molecular Weight
  • Tetradecanoylphorbol Acetate / pharmacology
  • Tumor Cells, Cultured


  • Immunoglobulins
  • Interleukins
  • Lipopolysaccharides
  • Interleukin-12
  • Interferon-gamma
  • Tetradecanoylphorbol Acetate