Construction of a fibroblast-associated tumor spheroid model based on collagen drop array chip

Abstract

Spheroid, a 3D aggregate of tumor cells in a spherical shape, has overcome the limitations of conventional 3D cell models to accurately mimic the in-vivo environment of a human body. The spheroids are often cultured with other primary cells and embedded in collagen drops to construct a spheroid–hydrogel model that better mimics the cell–cell and cell–extracellular matrix (ECM) interactions. However, the conventionally used methods of culturing and embedding spheroids into ECM has several shortcomings. The procedure of transferring a single spheroid at a time by manual pipetting results in the inconsistent arrangement and even loss or damage of the spheroid. Based on the previously introduced droplet contact-based spheroid transfer technique, we present a poly(dimethylsiloxane) and resin-based drop array chip and pillar array chip with alignment stoppers, which enhances the alignment between the chips for uniform placement of spheroids and eliminates the need to use a stereomicroscope while handling the cell models. The novel platform allows a homogeneous and time-efficient construction and diverse analysis of an array of fibroblast-associated glioblastoma multiforme spheroids embedded in collagen.