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The mechanism of polyplex internalization into cells: testing the GM1/caveolin-1 lipid raft mediated endocytosis pathway.

ABSTRACT: The GM1/caveolin-1 lipid raft mediated endocytosis mechanism was explored for generation 5 and 7 poly(amidoamine) dendrimer polyplexes employing the Cos-7, 293A, C6, HeLa, KB, and HepG2 cell lines. Expression levels of GM1 and caveolin-1 were measured using dot blot and Western blot, respectively. The level of GM1 in the cell plasma membrane was adjusted by incubation with exogenous GM1 or ganglioside inhibitor PPMP, and the level of CAV-1 was adjusted by upregulation with the adenovirus vector expressed caveolin-1 (AdCav-1). Cholera toxin B subunit was employed as a positive control for uptake in all cases. No evidence was found for a GM1/caveolin-1 lipid raft mediated endocytosis mechanism for the generation 5 and 7 poly(amidoamine) dendrimer polyplexes.

SUBMITTER: Qi R

PROVIDER: S-EPMC2826151 | biostudies-literature | 2010 Feb

REPOSITORIES: biostudies-literature

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The mechanism of polyplex internalization into cells: testing the GM1/caveolin-1 lipid raft mediated endocytosis pathway.

Qi Rong R Mullen Douglas G DG Baker James R JR Holl Mark M Banaszak MM

Molecular pharmaceutics 20100201 1

The GM1/caveolin-1 lipid raft mediated endocytosis mechanism was explored for generation 5 and 7 poly(amidoamine) dendrimer polyplexes employing the Cos-7, 293A, C6, HeLa, KB, and HepG2 cell lines. Expression levels of GM1 and caveolin-1 were measured using dot blot and Western blot, respectively. The level of GM1 in the cell plasma membrane was adjusted by incubation with exogenous GM1 or ganglioside inhibitor PPMP, and the level of CAV-1 was adjusted by upregulation with the adenovirus vector ...[more]

PMID: 20025295

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