IN-VIVO ROLE OF IL-10 AND IL-12 DURING DEVELOPMENT OF SJOGRENS-SYNDROME IN MRL LPR MICE/

Expression of local cytokine genes including interleukin 10 (IL-10) an d IL-12 was analyzed in the salivary gland tissues of MRL/lpr mice wit h Sjogren's syndrome. We demonstrate a significant role of IL-10 and I L-12 in vivo during development of Sjogren's syndrome in MRL/lpr mice. IL-10 mRNA expression was detected before the onset of disease and wa s upregulated during the course of autoimmune sialadenitis by RT-PCR. A predominant level of expression of IL-12 mRNA was also detected earl ier in the proinflammatory stage of autoimmune sialadenitis. Moreover, MHC class II (I-A(k)) mRNA was detected before the onset of inflammat ory lesions until older ages in the salivary glands of MRL/lpr mice. T hese results suggest that endogenous IL-10 and IL-12 may play importan t roles on immune-mediated destruction of the salivary glands during d evelopment of organ-specific autoimmunity in MRL/lpr mice. (C) 1996 Ac ademic Press, Inc.