LACRIMAL GLAND INNERVATION IS NOT ALTERED WITH THE ONSET AND PROGRESSION OF DISEASE IN A MURINE MODEL OF SJOGRENS-SYNDROME

The lacrimal glands of patients with Sjogren's syndrome develop extens ive lymphocytic infiltration, but also contain a large number of seemi ngly healthy looking acinar and ductal cells. Despite this, the secret ory function of this tissue is impaired, leading to aqueous tear-defic ient dry eye. This raises the possibility that there is a defect in th e neural innervation of the remaining portion of the lacrimal gland. T o test for this possibility, we used antibodies specific to various ma rkers of the parasympathetic, sympathetic, and sensory nerves and perf ormed immunohistochemical analyses of lacrimal glands from a murine mo del of Sjogren's syndrome, the MRL/Mp-Fas-lpr/lpr (MRL/lpr) and the co ntrol mice MRL/Mp-+/+ (MRL/+). Our results show that the MRL/lpr, but not the MRL/+, lacrimal glands become infiltrated with lymphocytes sta rting at 8 weeks of age which worsens by 12 and 18 weeks. The density and the pattern of parasympathetic, sympathetic, and sensory innervati on of the noninflamed acinar tissue of MRL/lpr lacrimal glands, at 4, 8, 12, and 18 weeks, is indistinguishable from that of age-matched con trol MRL/+ lacrimal glands. We conclude that the loss of the secretory function in Sjogren's syndrome lacrimal glands is not due to a loss o r decrease of its innervation. (C) 1998 Academic Press.