Cell Lines Expressing the Adenovirus E1A 12S Protein Derived from Rat Sublingual Glands

Mucous cells are highly regulated exocrine cells that synthesize and secrete high-molecular weight mucin glycoproteins, the major secretory component of salivary mucous glands such as the major sublingual and many of the minor salivary glands (1). Currently, the absence of well-differentiated salivary mucous cell lines has hindered the study of mechanisms regulating mucous cell-specific gene expression and exocrine secretion. Recently, He et al. used a retroviral vector system encoding for the adenovirus E1A 12S protein to establish immortalized cells from seromucous salivary glands, rat submandibular glands. They derived a clonal cell line, 2C-2, which increased cellular cAMP levels in response to beta -adrenergic agonist, and synthesized blood group A reactive oligosaccharides, similar to those present in the low-molecular weight mucin synthesized by rat submandibular glands. Therefore, we tested whether this retroviral vector system would immortalize rat sublingual cells and also provide cell lines expressing the mucous cell phenotype.