Stephan Reichl1, Karin Becker. 1. Institut für Pharmazeutische Technologie, Technische Universität Braunschweig, Braunschweig, Germany. S.Reichl@tu-bs.de
Abstract
OBJECTIVES: The kinetics of drug absorption for nasally administered drugs are often studied using excised mucosal tissue. To avoid the disadvantages of animal experiments, cellular in-vitro models have been established. This study describes the optimization of culture conditions for a model based on the RPMI 2650 cell line, and an evaluation of this model's value for drug absorption studies. METHODS: The cells were cultured in two serum-free media, serum-reduced variants or minimum essential medium (MEM) containing 5-20% serum. Cell seeding efficiency and proliferation behavior were evaluated in addition to viability and attachment following cryopreservation and thawing. Cells were cultured on different filter inserts for varying cultivation times. The epithelial barrier properties were determined by measuring transepithelial electrical resistance (TEER). Permeability was assessed using marker substances. KEY FINDINGS: Serum supplementation of medium was necessary for cultivation, whereas the serum concentration showed little impact on proliferation and attachment following cryopreservation. A pronounced dependence of TEER on medium and filter material was observed. An optimized model cultured with MEM containing 10% serum on polyethylene terephthalate exhibited permeability that was similar to excised nasal mucosa. CONCLUSIONS: These data indicate that this model could be an appropriate alternative to excised mucosa for the in-vitro evaluation of nasal drug absorption.
OBJECTIVES: The kinetics of drug absorption for nasally administered drugs are often studied using excised mucosal tissue. To avoid the disadvantages of animal experiments, cellular in-vitro models have been established. This study describes the optimization of culture conditions for a model based on the RPMI 2650 cell line, and an evaluation of this model's value for drug absorption studies. METHODS: The cells were cultured in two serum-free media, serum-reduced variants or minimum essential medium (MEM) containing 5-20% serum. Cell seeding efficiency and proliferation behavior were evaluated in addition to viability and attachment following cryopreservation and thawing. Cells were cultured on different filter inserts for varying cultivation times. The epithelial barrier properties were determined by measuring transepithelial electrical resistance (TEER). Permeability was assessed using marker substances. KEY FINDINGS: Serum supplementation of medium was necessary for cultivation, whereas the serum concentration showed little impact on proliferation and attachment following cryopreservation. A pronounced dependence of TEER on medium and filter material was observed. An optimized model cultured with MEM containing 10% serum on polyethylene terephthalate exhibited permeability that was similar to excised nasal mucosa. CONCLUSIONS: These data indicate that this model could be an appropriate alternative to excised mucosa for the in-vitro evaluation of nasal drug absorption.