title: Improved cellular uptake of chitosan-modified PLGA nanospheres by A549 cells.
abstract: The authors have previously developed poly(DL-lactic-co-glycolic acid) (PLGA) nanospheres (NSs) as a nanoparticulate drug carrier for pulmonary administration. The present study demonstrates that chitosan (CS)-modified PLGA NSs (CS-PLGA NSs) are preferentially taken up by human lung adenocarcinoma cells (A549). PLGA NSs prepared using a water-oil-water emulsion solvent evaporation method were surface-modified by adsorption of CS. The physicochemical parameters of PLGA NS, including average size and surface charge, were measured to identify which parameter influenced cellular uptake of PLGA NS. Uptake was confirmed using fluorescence spectrophotometry and was visualized in A549 cells with confocal laser scanning microscopy (CLSM). The cytotoxicities of non- and CS-PLGA NS systems were compared in vitro by MTS assay. Cellular uptake of PLGA NS increased with decreasing diameter to the submicron level and with CS-mediated surface modification. Cellular uptake of PLGA NS was energy dependent, as shown by a reduction in uptake at lower incubation temperatures and in hypertonic growth medium used as an inhibitor of clathrin-coated pit endocytosis. CS-PLGA NSs were taken up by A549 cells in an energy-dependent manner, suggesting a clathrin-mediated endocytic process. CS-PLGA NS demonstrated low cytotoxicity, similar to non-PLGA NS.
authors: Laboratory of Pharmaceutical Engineering, School of Pharmaceutical Science, Aichi Gakuin University, 1-100, Kusumoto, Chikusa, Nagoya, Aichi 464-8650, Japan.
authors: Kohei
authors: K
authors: Tahara
authors: Takeshi
authors: T
authors: Sakai
authors: Hiromitsu
authors: H
authors: Yamamoto
authors: Hirofumi
authors: H
authors: Takeuchi
authors: Naohide
authors: N
authors: Hirashima
authors: Yoshiaki
authors: Y
authors: Kawashima
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism*; D001693:Biological Transport, Active; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D002626:Chemistry, Pharmaceutical; D048271:Chitosan / Q000737:chemistry / Q000378:metabolism* / Q000633:toxicity; D002966:Clathrin / Q000378:metabolism; D003034:Coated Pits, Cell-Membrane / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004337:Drug Carriers; D004705:Endocytosis; D006801:Humans; D006982:Hypertonic Solutions; D007700:Kinetics; D019344:Lactic Acid / Q000737:chemistry / Q000378:metabolism* / Q000633:toxicity; D008175:Lung Neoplasms / Q000378:metabolism*; D018613:Microscopy, Confocal; D054118:Nanospheres; D010316:Particle Size; D011100:Polyglycolic Acid / Q000737:chemistry / Q000378:metabolism* / Q000633:toxicity; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D013050:Spectrometry, Fluorescence; D013499:Surface Properties; D013678:Technology, Pharmaceutical / Q000379:methods; D013696:Temperature
chemical_list: D002966:Clathrin; D004337:Drug Carriers; D006982:Hypertonic Solutions; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D048271:Chitosan