In vitro placental model optimization for nanoparticle transport studies

Abstract

Advances in biomedical nanotechnology raise hopes in patient populations but may also raise questions regarding biodistribution and biocompatibility, especially during pregnancy. Special consideration must be given to the placenta as a biological barrier because a pregnant woman's exposure to nanoparticles could have significant effects on the fetus developing in the womb. Therefore, the purpose of this study is to optimize an in vitro model for characterizing the transport of nanoparticles across human placental trophoblast cells. The growth of BeWo (clone b30) human placental choriocarcinoma cells for nanoparticle transport studies was characterized in terms of optimized Transwell® insert type and pore size, the investigation of barrier properties by transmission electron microscopy, tight junction staining, transepithelial electrical resistance, and fluorescein sodium transport. Following the determination of nontoxic concentrations of fluorescent polystyrene nanoparticles, the cellular uptake and transport of 50 nm and 100 nm diameter particles was measured using the in vitro BeWo cell model. Particle size measurements, fluorescence readings, and confocal microscopy indicated both cellular uptake of the fluorescent polystyrene nanoparticles and the transcellular transport of these particles from the apical (maternal) to the basolateral (fetal) compartment. Over the course of 24 hours, the apparent permeability across BeWo cells grown on polycarbonate membranes (3.0 µm pore size) was four times higher for the 50 nm particles compared with the 100 nm particles. The BeWo cell line has been optimized and shown to be a valid in vitro model for studying the transplacental transport of nanoparticles. Fluorescent polystyrene nanoparticle transport was size-dependent, as smaller particles reached the basal (fetal) compartment at a higher rate

Impact of in vitro digestion on gastrointestinal fate and uptake of silver nanoparticles with different surface modifications

“…Previously, we have shown minimal passage (less than 1%) of smaller (20 nm) AgNPs across a monolayer of Caco-2/M-cells exposed for 4 h (Bouwmeester et al 2011). For larger AgNPs it can be expected that the passage/transport is lower, in addition, we currently used membranes with a smaller pore size that might hinder the transport of the AgNPs (Cartwright et al 2012). However, in vivo studies indicate that silver can reach the systemic circulation, as oral feeding studies with rodents have reported low oral bioavailability of silver after exposure to AgNPs of different sizes (Loeschner et al 2011;van der Zande et al 2012).…”

Kinetics of silica nanoparticles in the human placenta

“…Menjoge et al reported low but quantifiable transfer of polyamidoamine dendrimers from maternal to fetal perfusate (Menjoge et al 2011). On the other hand, the transplacental transport of polystyrene NPs has been observed in both BeWo cells and in perfused placenta, and in both cases, the transport was shown to be size-dependent (Wick et al 2010; Cartwright et al 2012). …”

“…After 2 h of horizontal shaking (200 rpm) at 37°C, 100 μL lysate samples were analyzed for fluorescence to quantify NP uptake and attachment to the cells. The apparent permeability P e of the NPs across the cell monolayer was calculated as previously described in Cartwright et al (2012).…”

“…This model can be used for placental transport, metabolism, and toxicological studies and has been utilized to predict chemical exposure in pregnancy (Bode et al 2006; Mitra and Audus, 2009; Mørck et al 2010; Cartwright et al 2012). …”

Demonstration of the Clathrin- and Caveolin-Mediated Endocytosis at the Maternal–Fetal Barrier in Mouse Placenta after Intravenous Administration of Gold Nanoparticles

“…Because nanoparticles have properties, such as an extremely small size (less than 100 nm in diameter), high surface area per mass ratio and high potential chemical activities, adverse health effects from the daily application of nanoparticles have been seriously considered [5, 9, 10, 24, 32, 34]. The fetus is known to be susceptible to various toxic substances [1, 15, 39].…”