Increased Interleukin-6, Interferon-? and Tumour Necrosis Factor-a Production by Tonsillar Mononuclear Cells Stimulated with Alpha-Streptococci in Patients with Pustulosis Palmaris et Plantaris

Abstract

In vitro cytokine production by tonsillar mononuclear cells under culture conditions with or without lyophilized streptococcal antigens was measured by enzyme-linked immunosorbent assay (ELISA). Under culture conditions without any stimulus, a certain amount of interferon (IFN)-gamma, tumour necrosis factor (TNF)-alpha, and interleukin (IL)-6, was detected in the supernatant culture fluids from all 29 donors tested and just detectable levels of IL-1alpha and IL-2 were identified in 5 of 12 donors tested; but IL-4 and IL-5 were not detected in any supernatants from 21 donors tested. In 16 patients with pustulosis palmaris et plantaris (PPP), all three alpha-streptococcal antigens from Streptococcus, (S.) sanguis, S. salivarius and S. mitis induced production of IL-6. IFN-gamma and TNF-alpha by tonsillar mononuclear cells at a significant level. However, no significant induction of such cytokines by alpha-streptococcal stimulus was seen in 13 donors without PPP. No significant difference in cytokine production by tonsillar mononuclear cells was seen between the PPP and non-PPP subjects, when stimulated with S. pyogenes, Staphylococcus aureus Cowan I and pokeweed mitogen. In the experiments using tonsillar cell subsets, the cytokine inductions by alpha-streptococcal stimulus were found in monocyte-depleted cells as well as in purified T-cells. but not in B-cells. These data suggest that IL-6, IFN-gamma and TNF-alpha may play an important role in immunological reactions in the tonsils and that a hyper-immune response to some of alpha-streptococcal antigens through increased production of such cytokines by tonsillar mononuclear cells, to which T-cells mainly contribute, may play a key role in the pathogenesis of PPP.