Uptake and transport of pullulan acetate nanoparticles in the BeWo b30 placental barrier cell model

Abstract

IntroductionNanomedicine has shown a great potential in perinatal medicine because of its characteristics of sustained, controlled release and targeting ability; on the other hand, it may also lead to unexpected toxicities such as embryotoxicity and even malformation after crossing the placental barrier, but data concerning transplacental transport are scarce. Pullulan acetate (PA) nanoparticles (NPs) are a promising nanocarrier derived from natural polysaccharide; however, their transplacental transport ability and mechanism are unknown.Materials and methodsIn this study, fluorescein isothiocyanate (FITC) conjugated PA (PA-FITC) was synthesized. PA-FITC NPs were characterized by dynamic light scattering, transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The cytotoxicity of PA-FITC NPs at concentrations of 15, 30, 60, 125, 250, 500, 1,000 and 2,000 μg/mL was studied by cell counting kit-8. The human chorionic gonadotrophin (HCG) cytokine assay was conducted to evaluate the biological function of BeWo b30 cells. Endocytic mechanisms of PA-FITC NPs were investigated via fluorescence analysis. The monolayer properties were characterized by TEM, tight junction staining, transepithelial electrical resistance and fluorescein sodium transportation. The transport ability was measured in the cell based transwell model by confocal imaging and SEM.ResultsPA-FITC NPs were almost spherical shape with a size range of 200–300 nm. Cell viability of BeWo b30 cells was up to 100% in all groups. The concentrations of HCG increased with increasing numbers of cells and culture time, which showed the good biological function of BeWo b30 cells. PA-FITC NPs were rapidly endocytosed through caveolae-mediated endocytosis and pinocytosis, with uptake inhibition rates with nystatin (NY) and colchicines (Col) of 55% and 51% respectively. BeWo b30 cell monolayer was formed over 5 days. PA-FITC NPs were found in the cytoplasm of cells on the transwell membranes; while some NPs were found in the basolateral (fetal) compartment over 24 h.ConclusionIn summary, PA-FITC NPs are nontoxic, can cross the blood-placental barrier, and show mainly internalization to BeWo b30 cells through caveolae-mediated endocytosis and pinocytosis pathways, major via the former pathway. The results could benefit the adjustment and control of the transplacental transport of nanomedicines.

Nanoparticles Based on Hydrophobic Polysaccharide Derivatives—Formation Principles, Characterization Techniques, and Biomedical Applications

“…NP derived from pullulan acetate are biocompatible and showed no cytotoxicity, neither in cell viability assays nor in animal tests. [ 132,133 ] Thus, they received interest as carrier for drug delivery purposes (see chapter 5.3.). Pullulan acetates have been further modified prior to the particle formation by derivatization with additional substituents to enhance drug encapsulation and/or release efficiency as well as to tailor the interaction with cells.…”

Influence of Liposomes’ and Lipoplexes’ Physicochemical Characteristics on Their Uptake Rate and Mechanisms by the Placenta

“…One study has evaluated the internalization of gold nanoparticles on placental explants and revealed their translocation through the maternal-fetal barrier by clathrin-mediated endocytosis [ 33 ]. Tang et al have demonstrated that the main placental internalization mechanisms of negatively charged pullulan acetate nanoparticles by the BeWo cell line were pinocytosis and caveolae-mediated endocytosis [ 34 ]. More recently, the internalization of positively charged polymeric nanoparticles was related to dynamin dependent processes: mainly clathrin-mediated endocytosis [ 35 ].…”

Imaging techniques in nanomedical research

“…46 CFM allowed testing the efficacy of paclitaxel-loaded expansile NPs in a mesothelioma spheroid model, 47 the uptake and distribution of nanodiamonds in different cell lines and organ slices, 48 and the ability of Pullulan acetate NPs to pass the placental barrier in in vitro cell monolayers. 49 Furthermore, CFM was frequently used in combination with other imaging/microscopy techniques.…”