RESUMO
Poloxamers are water-soluble polymers that are widely used in cell culture bioprocessing to protect cells against shearing forces. Use of poor-quality poloxamers may lead to a drastic reduction in cell growth, viabilities and productivities in cell culture-based manufacturing. In order to evaluate poloxamer quality and promote more consistent performance, a rapid cell membrane adhesion to hydrocarbon assay was developed based on the adhesive properties of cell membranes to selective hydrocarbons. The assay can identify a poor-performing poloxamer characterized by significant drop in viable cell density and percent viability. The assay was verified across multiple good and bad poloxamer lots, and the results were in agreement with established cell growth and high-performance liquid chromatography assays.
Assuntos
Técnicas de Cultura de Células/métodos , Sobrevivência Celular/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Poloxâmero/farmacologia , Substâncias Protetoras/farmacologia , Animais , Células CHO , Contagem de Células/métodos , Técnicas de Cultura de Células/economia , Proliferação de Células/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão/métodos , Cricetulus , Células HEK293 , Humanos , Poloxâmero/análise , Substâncias Protetoras/análise , Fatores de TempoRESUMO
The amyloid-beta (Abeta) cascade hypothesis of Alzheimer's disease (AD) has dominated research and subsequent therapeutic drug development for over two decades. Central to this hypothesis is the observation that Abeta is elevated in AD patients and that the disease is ultimately characterized by the central deposition of insoluble senile plaques. More recent evidence, however, suggests that the presence or absence of plaque is insufficient to fully account for the deleterious role of elevated Abeta in AD. Such studies support the basis for an alternate interpretation of the Abeta cascade hypothesis. Namely, that soluble oligomers of Abeta (i.e., ADDLs) accumulate and cause functional deficits prior to overt neuronal cell death or plaque deposition. Accordingly, the following review focuses on research describing the preparation and functional activity of ADDLs in vitro and in vivo. These studies provide the basis for an alternate, ADDL-based, view of the Abeta cascade hypothesis and accounts for the disconnect between plaque burden and cognitive deficits. Possible therapeutic approaches aimed at lowering ADDLs in AD patients are also considered.