ABSTRACT
The objective of this research was to examine the human sub-bronchial gland cell line, Calu-3, and assess its potential as a metabolic and transport model to study drug delivery to the respiratory epithelium. The present studies were conducted using Calu-3 cells grown in Transwells(R) or in multiwell cluster plates. TEER values for Calu-3 monolayers were determined using the World Precision Instrument Voltohmmeter and STX-2 electrode. The results confirmed that Calu-3 cells form tight monolayers and give appreciable TEER values in culture when grown under air-interface conditions. Permeability data for small lipophilic molecules across Calu-3 monolayers suggested that the cell line is a suitable model to examine the transport of low molecular weight substances and xenobiotics. Calu-3 cells were also found to efflux FITC-transferrin (MW 80000) in a polarized manner. The metabolic capacity of Calu-3 cells was also examined. The P4501A1 and P4502B isozymes were determined to be functional, but not inducible, with fluorescent resorufin assays. The data indicated that the Calu-3 cell line may be useful for studying the contributions of bronchial epithelial cells to mechanisms of drug delivery at the respiratory epithelium.
Subject(s)
Aryl Hydrocarbon Hydroxylases , Cells, Cultured/cytology , Drug Evaluation, Preclinical/methods , Respiratory Mucosa/cytology , Administration, Inhalation , Cells, Cultured/metabolism , Cytochrome P-450 CYP1A1/metabolism , Cytochrome P-450 CYP2B6 , Cytochrome P-450 Enzyme System/metabolism , Fluorescent Dyes/metabolism , Humans , Isoquinolines/metabolism , Oxidoreductases, N-Demethylating/metabolism , Respiratory Mucosa/metabolismSubject(s)
Anti-Ulcer Agents/pharmacology , Epidermal Growth Factor/drug effects , Fibroblast Growth Factor 2/drug effects , Gastric Mucosa/drug effects , Sucralfate/pharmacology , Cell Division/drug effects , Drug Evaluation, Preclinical , Epidermal Growth Factor/metabolism , Epithelial Cells , Epithelium/drug effects , Epithelium/metabolism , Fibroblast Growth Factor 2/metabolism , Gastric Mucosa/cytology , Gastric Mucosa/metabolism , Humans , Hydrogen-Ion Concentration , Models, Biological , Tumor Cells, CulturedABSTRACT
Primary rat gastric cell cultures were investigated as an in vitro model for evaluating antiulcer agents. Following exposure to concentrations of up to 5 mg/mL of an antiulcer agent sucralfate, an aluminum hydroxide complex of sucrose octasulfate, cultured cells were treated with either pH 3.5 medium or 3.5 mM indomethacin. Cytoprotection was evaluated by colony forming efficiency, neutral red uptake, and 3-(4,5-dimethyl-2-thiazoyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) hydrolysis. By each measure, and depending on damaging agent, 2 and 5 mg/mL sucralfate provided partial (50% of untreated control) to near-complete (90% of untreated control) cytoprotection, respectively. Aluminum hydroxide also provided partial (55% of untreated control) to near-complete (more than 90% of untreated control) cytoprotection at 2 and 5 mg/mL, respectively, for the pH 3.5 medium-induced damage. Over a concentration range of 0.05 to 5 mg/mL, the potassium salt of sucrose octasulfate, KSOS, stimulated cell growth up to 40-60% over untreated controls but had little or no cytoprotective action in the presence of either 3.5 mM indomethacin or pH 3.5 medium. Overall results suggested that sucralfate may have at least two roles in influencing gastric epithelial cell function, cytoprotection and stimulation of cell growth in vitro. These observations serve as a basis for further study of in vitro models in evaluating the cytoprotective activity of antiulcer agents and their respective mechanisms of action.