Lacrimal gland primary acinar cell culture: the role of insulin

Abstract

The condition of lacrimal glands (LG) is influenced by components of the immune, neural, and endocrine systems (1)(2)(3)(4)(5) . Insulin is thought to be of major importance, based on observations related to its deprivation in diabetes mellitus (DM), on LG, tear film, and ocular surface in humans, animal models, and in culture (6)(7)(8) . Lacrimal gland acinar cell (LGAC) culture is an appropriate model for improving the understanding of the influence of insulin on these cells.In previous studies, the culture of LGACs from different species was performed over an average period of 21 days (9,10) . Several attempts to enhance the growth of acinar cells in culture have been made, but after a span of approximately 3 weeks, LGACs exhibited decreased viability, with high numbers of apoptotic cells (11)(12)(13)(14) . Exocrine acinar cells are fragile, post-mitotic epithelial cells with marked polarity. This indicates that the apical and basal sides are clearly positioned but also that intracellular organelles are located at one or the other pole, depending on their cellular functions. Thus, an adequate extracellular matrix and other specific ingredients are needed in the culture media to mimic in vivo conditions (15,16) . The handling during isolation and culture procedure of LGACs should be gentle ABSTRACT Purpose: The goal of the present study was to establish a protocol for primary culture of lacrimal gland acinar cells (LGACs) and to assess the effect of adding insulin to the culture media. Methods:LGACs were isolated and cultured from lacrimal glands of Wistar male rats. The study outcomes included cell number, viability, and peroxidase release over time and in response to three concentrations of insulin (0.5, 5.0, and 50.0 μg/mL). Results: In LGAC primary culture, cells started to form clusters by day 3. There was a time-response pattern of peroxidase release, which rose by day 6, in response to carbachol. Culture viability lasted for 12 days. An insulin concentration of 5.0 μg/mL in the culture medium resulted in higher viability and secretory capacity. Conclusions:The present method simplifies the isolation and culture of LGACs. The data confirmed the relevance of adding insulin to maintain LGACs in culture. Keywords