Placenta‐on‐a‐Chip: In Vitro Study of Caffeine Transport across Placental Barrier Using Liquid Chromatography Mass Spectrometry

Abstract

Due to the particular structure and functionality of the placenta, most current human placenta drug testing methods are limited to animal models, conventional cell testing, and cohort/controlled testing. Previous studies have produced inconsistent results due to physiological differences between humans and animals and limited availability of human and/or animal models for controlled testing. To overcome these challenges, a placenta‐on‐a‐chip system is developed for studying the exchange of substances to and from the placenta. Caffeine transport across the placental barrier is studied because caffeine is a xenobiotic widely consumed on a daily basis. Since a fetus does not carry the enzymes that inactivate caffeine, when it crosses a placental barrier, high caffeine intake may harm the fetus, so it is important to quantify the rate of caffeine transport across the placenta. In this study, a caffeine concentration of 0.25 mg mL −1 is introduced into the maternal channel, and the resulting changes are observed over a span of 7.5 h. A steady caffeine concentration of 0.1513 mg mL −1 is reached on the maternal side after 6.5 h, and a 0.0033 mg mL −1 concentration on the fetal side is achieved after 5 h.

Maternally administered naltrexone and its major active metabolite 6β-naltrexol transport across the placental barrierin vitro

“…Previous studies have proven the validity of using placenta-on-a-chip for assessing and replicating different drug transport analysis while mimicking physiological function of human placenta in vitro. [15][16][17][18][19][20][21] Through our most recent study, we analyzed caffeine transport across our fabricated microchip, and proved the model to be compatible with withstanding xenobiotic exposure. 21 Therefore, since placentaon-a-chip has yet to be tested with opioid contact, our study provides the first appraisal examining NTX and 6β-naltrexol on an organ-on-a-chip.…”

“…The co-cultured microfluidic device consisted of three layers (Figure 1 (g)) that replicate a human placenta in vitro, similar to that from a previous study. 21 The top layer, or maternal channel, was composed of BeWo cells that represent the trophoblastic epithelium of the human placenta. Beneath the top layer is a thin semipermeable membrane that imitates the human placental barrier, and adhered to the bottom of the porous membrane is the fetal channel, comprised of HUVECs, to recapitulate the endothelium of a human placenta.…”

“…35,36 As shown in Figure 2 (e), a dense layer of microvilli was observed on the fluorescence microscopy images, and variability this dense layer was detected along the apical surface of the trophoblast cell layer, possibly attributed to differing fluid shear stresses caused by trophoblast cells forming a 3D structure inside the maternal channel, as previously described. 21 Previous studies for visualizing microvilli under static conditions have resulted in sparse microvillar surfaces. 15,17,19 In conjunction with such previous studies, microvilli visualized herein dynamic flow conditions have demonstrated elongated microvilli formation in our study.…”

“…HUVECs and BeWo were chosen to present the cells at the fetal and maternal interfaces, respectively, as previously described. 21 BeWo cells (ATCC) were cultured in Kaighn's Modification of Ham's F-12K medium (Thermofisher), supplemented with growth factors and 10% fetal bovine serum (FBS, Gibco). HUVECs (Lonza) were cultured in endothelial growth medium (EGM, R&D Systems).…”

“…This study's intended purpose was to evaluate opioid transport in our placenta-on-a-chip model, and this stage of testing is made possible through the system and foundation of the placenta-ona-chip, microfluidic device. [18][19][20][21] Microfluidic devices provide us with the ability to culture and manage cellular and subcellular environments within our microchip, maintain fixed compositions of our cell lines, and replicate fluid movement in parallel layers. 11,[22][23][24][25][26][27][28] Our microfluidic device (( Figure 1 (d)-(f-f)) was fabricated using standard lithography techniques.…”