CYTOKINE EXPRESSION AND PRODUCTION BY TONSILLAR LYMPHOCYTES

Expression of various cytokines in the tonsillar compartments, and in vitro cytokine production and cytokine mRNA expression by tonsillar ly mphocytes (TL), were investigated. In immunohistological analysis, a w ide variety of cytokines such as interleukin (IL)-1 beta, IL-2, IL-4, IL-5, IL-10 was expressed intensively in the lyumphoepithelial symbios is (LES). A certain number of cells producing IL-6, interferon (IFN)-g amma, and tumor necrosis factor (TNF)-alpha was distributed not only i n the LES but also in the extrafollicular area. A significant amount o f IL-6, IFN-gamma, and TNF-alpha was detected by enzyme-linked immunos orbent assay in the culture supernatants of TL cultured with streptoco ccal antigen, even without any mitogens. Furthermore, mRNA of IL-6, IF N-gamma, and TNF-alpha was determined by reverse transcription polymer ase chain reaction on the TL freshly isolated and with streptococcal s timulated antigen, whereas, production of IL-1 alpha, IL-4, and IL-5, and expression of their mRNA were not found on TL with or without stre ptococcal stimulation. These data indicate that tonsils are highly act ive immunological organs containing a wide variety of cytokine-produci ng cells, and suggest that IFN-gamma, TNF-alpha, and IL-6 may play an important role on the immune response to bacteria in the tonsil.