Oral submucous fibrosis patients have altered levels of cytokine production

Oral submucous fibrosis (OSF) is a pre-malignant fibrotic lesion of the mouth in betel quid chewers and is characterised by dense bands of collagen in the juxta-epithelial region preceded by inflammation. We have investigated the spontaneous and stimulated production of cytokines by peripheral blood mononuclear cells (PBMC) from OSF patients and compared them with genetically-related relatives, Indian and Caucasian control subjects. The cytokines studied included: interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6), interleukin-8 (IL-8), tumour necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma). The results show: a) significant differences in the stimulated versus nonstimulated levels of IL-1 beta, IL-6, IL-8 and TNF-alpha but not of IFN-gamma production by patients, and in the relatives' stimulated versus non-stimulated levels of IL-1 beta, IL-6 and IFN-gamma; b) no difference in the spontaneous cytokine production between any two groups; and c) significant increases in the patients' stimulated cytokines compared to the Caucasian and Indian controls (P less than or equal to 0.050). These results demonstrate increased levels of proinflammatory cytokines and reduced anti-fibrotic IFN-gamma in patients with OSF, which may be central to the pathogenesis of OSF.