Additional experiments were performed where HBE cells were incubated with antibodies to integrin 6 or to an IgG2a antibody (Figure 4F)

Additional experiments were performed where HBE cells were incubated with antibodies to integrin 6 or to an IgG2a antibody (Figure 4F). spheroids at Day 7, demonstrating that laminin (a major component of the basement membrane matrix), the cell surface receptor integrin 6, and the cell junction marker E-cadherin have functional functions in HBE acinar morphogenesis. No significant variability was detected in the average size of glandular acini created by HBE cells from two normal individuals. These results exhibited that this model system is usually reproducible, stable, and potentially useful for studies of glandular differentiation and hyperplasia. model system of respiratory tract glandular acini and will facilitate investigations into mechanisms that lead to the submucosal glandular hyperplasia manifested in chronic disease of the respiratory tract (chronic obstructive pulmonary disease, cystic fibrosis, chronic rhinosinusitis). Submucosal glands are a major source of mucus in the respiratory tract. Hyperplasia and/or hypertrophy of submucosal glands contribute to mucus overproduction in chronic airway diseases, such as cystic fibrosis (1C3), asthma (4), chronic obstructive pulmonary diseases (5), and chronic rhinosinusitis (6, 7). Even though morphogenesis of submucosal glands during fetal development is well explained (8, 9), glandular hyperplasia in respiratory tract mucosa is usually markedly understudied, reflecting primarily the lack of an cell model system whereby respiratory tract epithelial cells differentiate into glandular cells. The basement membrane extracellular matrix (ECM) functions as a scaffold for tissue morphogenesis and contains biologically active components that provide cues for cell proliferation and differentiation (10, 11). Various types of main epithelial cells, including those from salivary and mammary glands as well as cells from your intestine, pancreas and oviduct, have been shown to differentiate into three-dimensional (3D) structures with glandular acini when produced on a basement Epibrassinolide membrane ECM (12). The most commonly used ECM for 3D cell culture is usually Matrigel, an extract isolated from Engelbreth-Holm-Swarm murine tumors and composed of laminin (61%), collagen IV (30%) and entactin (7%) (10, 13). It has been extensively used to investigate the differentiation of mammary cells and cell lines into 3D acinar structures (11, 14) as well as branching morphogenesis in murine salivary glands (15). Lung epithelial cells from distal regions of rodent airways have also been produced on Matrigel. Rat lung cells undergo alveolar type II differentiation (16) and those from mice undergo budding (17). However, you will find no reports describing whether proximal, e.g., bronchial or tracheal, airway epithelial cells differentiate into glandular acini when produced on a basement membrane matrix. On the other hand, research over the last 25 years has shown that main epithelial cells from human bronchi or rodent trachea are capable of differentiating into a conducting airway epithelium. Human bronchial epithelial (HBE) cells produced on collagen-coated Transwell membranes Epibrassinolide under airCliquid interface (ALI) conditions differentiate to form an epithelium with ciliated, goblet, and basal cells that morphologically mimics human airway epithelium [examined in (18, 19)]. Similarly, hamster (20), guinea pig (21) and murine (22) tracheal epithelial cells differentiate to an epithelium with ciliated, secretory, and basal cells that morphologically mimic epithelium observed More recently, it has been shown Rabbit Polyclonal to GPR113 that basal cells isolated from murine tracheal and human bronchial epithelium, when immersed in Matrigel plated on Transwell membranes and produced under ALI conditions, differentiate into tracheospheres or bronchosperes that have ciliated cells Epibrassinolide lining a hollow Epibrassinolide lumen but lack detectable secretory cells (23). Taken together, this information suggests that main HBE cells, which contain multipotent precursor cells capable of differentiating into a conducting airway epithelium or bronchospheres, would also differentiate into glandular acini in the proper context. Submucosal glands are not observed in the ALI model system; however, MUC5B mucin, a gene product whose expression is normally restricted to glandular mucosal cells in human lower respiratory tract tissues (24), is usually well-expressed and secreted in the ALI system (25). We.