Multiwell capillarity-based microfluidic device for the study of 3D tumour tissue-2D endothelium interactions and drug screening in co-culture models

Abstract

The tumour microenvironment is very complex, and essential in tumour development and drug resistance. The endothelium is critical in the tumour microenvironment: it provides nutrients and oxygen to the tumour and is essential for systemic drug delivery. Therefore, we report a simple, user-friendly microfluidic device for co-culture of a 3D breast tumour model and a 2D endothelium model for cross-talk and drug delivery studies. First, we demonstrated the endothelium was functional, whereas the tumour model exhibited in vivo features, e.g., oxygen gradients and preferential proliferation of cells with better access to nutrients and oxygen. Next, we observed the endothelium structure lost its integrity in the co-culture. Following this, we evaluated two drug formulations of TRAIL (TNF-related apoptosis inducing ligand): soluble and anchored to a LUV (large unilamellar vesicle). Both diffused through the endothelium, LUV-TRAIL being more efficient in killing tumour cells, showing no effect on the integrity of endothelium. Overall, we have developed a simple capillary force-based microfluidic device for 2D and 3D cell co-cultures. Our device allows high-throughput approaches, patterning different cell types and generating gradients without specialised equipment. We anticipate this microfluidic device will facilitate drug screening in a relevant microenvironment thanks to its simple, effective and user-friendly operation.

Development of a Microfluidic Array to Study Drug Response in Breast Cancer

“…However, this design was fabricated in PDMS via soft lithography. To improve on some of the design drawbacks of that device (e.g., labor-intense fabrication and design operation, PDMS sequestration of small hydrophobic molecules), we designed a PS-based version of the device [18]. Firstly, the device was designed to include multiple micro-culture chambers matching the spacing distance center-to-center used in conventional 96 well-plates for compatibility with multi-channel micro-pipettes, automated pipetting systems, and automated imaging platforms (i.e., plate readers) (Figure 1A–E).…”

“…Next, the design included a side microchannel that connected several devices together. The dimensions of the hydrogel loading microchannel ensured fluid with different viscosities (e.g., water, PBS, collagen, Matrigel) spontaneously flowed via capillary forces through the microchannel and filled the microchambers [18,19]. Once the hydrogel is polymerized, the sacrificial PDMS rod can be removed for cell seeding as required (Figure 1H), therefore it does not get in contact with cells or cell culture media.…”

“…Although PDMS has excellent optical clarity, flexibility, and gas permeation properties, PDMS can nonspecifically absorb small molecules, including certain drugs [17]. Polystyrene (PS) presents a more promising alternative due to its mass-production potential, impermeability to small hydrophobic molecules, and biocompatibility [18].…”

Organotypic primary blood vessel models of clear cell renal cell carcinoma for single-patient clinical trials

“…On the other hand, vessel confluency was calculated on phalloidin images after a binarization of images using a set threshold as previously described. 24,49 Visual inspection of each threshold confirmed the accuracy in representing the initial image. Then, a consistent region of interest was defined to include only the vessel (i.e., not surrounding areas or sprouts).…”

Endothelial cell culture in microfluidic devices for investigating microvascular processes

“…63 Finally, utilizing the multi-cell co-culture of microfluidic devices will enable the development of more physiological environments that encompass multiple cell types and organ systems. 64,65 Overall, endothelialized microfluidic technology has enabled researchers to study microvascular phenomena that were previously inaccessible via conventional models. As the field of endothelialized microfluidics continues to mature and advance using sophisticated technologies, researchers will have new avenues at their disposal to study the complex cellular interactions that occur within the microvasculature.…”