Analysis of cytomegalovirus infection and replication in acinar epithelial cells of the rat lacrimal gland.

PURPOSE The objectives of this investigation were threefold: to advance understanding of the nature and impact of herpesvirus infection in the lacrimal gland; to determine the influence of gender and sex hormones on viral infectivity and replication capacity in lacrimal tissue; and to compare the susceptibilities of lacrimal, submandibular, and parotid cells to viral invasion. METHODS Acinar epithelial cells were isolated from lacrimal or salivary glands from intact, orchiectomized, ovariectomized, or sham-operated rats, cultured on Matrigel in serum-free media, and briefly exposed to rat cytomegalovirus (RCMV). Cells were then incubated for varying time intervals, and RCMV titers and secretory component (SC) levels in media or cell extracts were measured by plaque assay or radioimmunoassay. Exocrine glands also were obtained from rats after RCMV inoculation in vivo and were analyzed for viral infection. RESULTS These findings demonstrated that RCMV invades the rat lacrimal gland after intravenous or intraperitoneal viral inoculation; RCMV infects and undergoes a time-, dose-, strain-, and gender-dependent replication in acinar epithelial cells from rat lacrimal tissue; the magnitude of RCMV replication in acinar epithelial cells in vitro may, in fact, induce an acute increase in the cellular production of SC; and the extent of viral replication in lacrimal and salivary gland epithelial cells displays distinct, tissue-specific variations. CONCLUSIONS The herpesvirus RCMV invades and replicates in acinar epithelial cells from the rat lacrimal gland. The magnitude of the viral infection may be significantly influenced by gender and alterations in the hormonal environment.