INTERLEUKIN-10 PROMOTES ANTICOLLAGEN ANTIBODY-PRODUCTION IN TYPE-I DIABETIC PERIPHERAL B-LYMPHOCYTES

Previous studies have shown that type I diabetes (IDDM) increases the risk of developing periodontitis by 2-3-fold. IDDM patients exhibit de struction of the pancreatic beta cells, most probably caused by an aut oimmune reaction. Evidence is accumulating to support the role of the autoimmune response in periodontal pathogenesis. A cytokine, interleuk in (IL)-10, has been reported to selectively promote the expansion of a B lymphocyte lineage (CD5/LY1/B1) which has the propensity for secre ting high levels of autoantibody. Therefore, the purpose of this proje ct was to evaluate IL-10 production, percentage of CD5 B cells and the frequency of anti-collagen secreting cells in peripheral blood mononu clear cells of age, gender and race matched IDDM patients and controls . IL-10 production was evaluated by an ELISA using the supernatant of adherent peripheral blood cells cultured for 24 h in the presence of P orphyromonas gingivalis lipopolysaccharide (LPS). In 8 of 31 patients, IL-10 levels were significantly increased in IDDM compared to control s and a higher percentage of CD5 B cells was also observed by flow cyt ometry. In addition, these patients exhibited a higher frequency of an ti-collagen secreting cells as elucidated by an ELISPOT. Moreover, tre atment with a neutralizing anti-IL-10 antibody diminished the anti-col lagen antibody response by 70%. These findings support the concept tha t a subset of IDDM patients possess an extremely robust IL-10 response following exposure to Gram-negative LPS, which could predispose them to the development of periodontitis through a heightened autoimmune me chanism.