IL-4 production is increased in cigarette smokers

Clin Exp Immunol. 1994 Feb;95(2):333-6. doi: 10.1111/j.1365-2249.1994.tb06533.x.


Cigarette smoking has been associated with both increases in serum levels of total IgE and an increased risk of developing allergic-like symptoms. IL-4 and interferon-gamma (IFN-gamma) have reciprocal roles in the regulation of IgE synthesis, and as such prompted us to evaluate, in smokers, the production of these two cytokines. We demonstrate that phytohaemagglutinin (PHA)-induced IL-4 production by peripheral blood mononuclear cells (PBMC) of smokers (n = 19) is significantly higher than that of non-smokers (n = 10, P < 0.005). In addition, PBMC from heavy smokers, defined by the number of cigarettes smoked per day, produced significantly higher levels of IL-4 than those of light smokers. No difference between the groups was found for IFN-gamma production. Our data suggest an imbalance in cytokine production occurring in individuals who smoke. This imbalance, favouring IL-4 production, may be part of the mechanism responsible for the observed increases in serum IgE and allergic-like symptoms associated with cigarette smoking.

MeSH terms

  • Adult
  • Female
  • Humans
  • Hypersensitivity / etiology
  • Immunoglobulin E / blood
  • Interferon-gamma / biosynthesis
  • Interleukin-4 / biosynthesis*
  • Male
  • Middle Aged
  • Smoking / adverse effects
  • Smoking / immunology*
  • T-Lymphocytes / immunology


  • Interleukin-4
  • Immunoglobulin E
  • Interferon-gamma