Purchase this article with an account.
Michael Rivera, Alline Lelis, Konrad Kauper, Bruce Bouchard, Vincent Ling; Investigation and Optimization of ECT Hold Conditions and Their Impact on Protein Expression. Invest. Ophthalmol. Vis. Sci. 2011;52(14):3227.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Neurotech’s encapsulated cell technology (ECT) platform utilizes genetically engineered cells to secrete therapeutic proteins from an implantable hollow fiber capsule. Several studies were initiated to investigate environmental elements and their impact on secretion rates and cell viability. Variables such as hold temperature, encapsulation density, culture media supplements, and concentration of media analytes and metabolites were all evaluated for their role in device expression, and potential implications for ECT optimization.
Devices used in these studies were manufactured using polymer membrane encapsulated cells genetically engineered to secrete a VEGF inhibitor molecule. Various culture media supplements including, but not limited to, Vitamin A, Lutein, and Cholesterol were added in serial concentrations to evaluate their impact on device secretion and long term stability. Additionally, media samples were measured for key analytes and metabolites for evaluation of their depletion or accumulation, and the corresponding device performance under those conditions. Device stability and secretion levels of VEGF inhibitor were quantified by ELISA. Evaluation of media analytes and metabolites was performed using a Nova Biomedical chemistry analyzer.
Several of the environmental conditions including hold temperature, cholesterol supplementation, and media ammonium concentration resulted in significant changes in device performance. Encapsulated cells responded with both increased expression levels of VEGF inhibitor, exceeding a microgram per day level, and decreased protein expression, depending on condition, demonstrating the potential ability to selectively control ECT secretion, and revealing key environmental manipulations to achieve optimization.
ECT in vitro performance can be optimized through the use of key supplements and encapsulation conditions. Long-term stability and elevated expression of a VEGF inhibiting molecule was achieved for a period of at least one month.
This PDF is available to Subscribers Only