Periodic Reporting for period 1 - GliomaChip (Glioma on a chip: Probing Glioma Cell Invasion and Gliomagenesis on a Multiplexed Chip)
Période du rapport: 2020-09-01 au 2022-08-31
28% of all primary brain tumors and central nervous system tumors and 80% of malignant tumors are gliomas, which arise from the supportive tissues in the brain. Yet, our ability to effectively treat these cancers is limited by our knowledge of the disease and our ability to test new treatments on accurate models. Current methods of biological research rely on animal testing and two-dimensional tissue cultures but fail to provide physiologically accurate models of human tissue. This demonstrates a pressing need for convenient, physiologically relevant tissue models to advance biomedical research. Advances in microfluidics and cell encapsulation within hydrogels have made significant strides in trying to meet these needs, but the potential to use these technologies for engineering physiologically relevant tissue models has yet to be fully realized. Here, our objective was to investigate cancer biology using a microfluidic device with three-dimensional (3D) micro-patterned neural constructs that may be subjected to flow through microfluidic channels. Briefly, our conclusions are: 1) Our in vitro microfluidic platform with embedded gelatin methacryloyl (GelMA) hydrogels was a viable platform for 3D neural cell culture studies and was structurally stable over long periods. 2) GelMA exhibited the desired biomechanical properties, and the viability of cells was more than 80% for seven days. 3) This work demonstrated a viable strategy to conduct co-culturing experiments as well as modeling invasion and migration events. 4) This microfluidic assay may have application in drug delivery and dosage optimization studies.
Advances in microfabrication and biomaterials have enabled the development of microfluidic chips for studying tissue and organ models. While these platforms have been developed primarily for modeling human diseases, they are also used to uncover cellular and molecular mechanisms through in vitro studies, especially in the neurovascular system, where physiological mechanisms and three-dimensional (3D) architecture are difficult to reconstruct via conventional assays. An extracellular matrix (ECM) model with a stable structure possessing the ability to mimic the natural extracellular environment of the cell efficiently is useful for tissue engineering applications. Conventionally used techniques for this purpose, for example, Matrigels, have drawbacks of owning complex fabrication procedures, in some cases not efficient enough in terms of functionality and expenses. In this project, we developed a neural-tissue-on-a-chip device with three-dimensional (3D) micro-patterned neurovascular constructs that may be subjected to flow through microfluidic channels. We proposed a fabrication protocol for GelMA hydrogel, which has shown structural stability and the ability to imitate the natural environment of the cell accurately, inside a microfluidic chip co-culturing of two human cell lines (HU-VEC and SH-SHY5Y). Briefly, GelMA was deposited inside the microfluidic setup using photopolymerization and investigated for its effects on cellular viability. The transparent surface of the polydimethylsiloxane in the microfluidic chip allowed the photoinitiation process through a light source. First, GelMA was synthesized, and its properties, such as surface morphology and structure, were identified by Fourier transform infrared spectrophotometry, field emission electron microscopy, and atomic force microscopy. In addition, the swelling behavior of the GelMA in the microfluidic chip was imaged, as swelling is one of the main factors for a cell-encapsulated hydrogel for continuous nutrition to stay viable for longer durations. We disseminated these results via two peer-reviewed journal articles and a website, and the commercialization potential of our studies by attending an incubation and entrepreneurship studies program at Koc University.
The structural properties and bioavailability of GelMA hydrogels were examined inside and outside of the microfluidic chip with the co-culturing of a neurovascular tissue structure. In addition to the neurovascular research applications of this setup, the developed environment can also be suitable for modeling various types of cancer and examining the invasion and migration of various types of cancer or tumor cells. Furthermore, this platform can enable chemotaxis studies, allowing chemoattractants to be used for the promotion of the migration of cells from the selected channels. As the design of the microfluidic devices enables the user to “mold” their hydrogel patterns easily without a surface coating or chemical or mechanical functionalization, patterning the desired shape and sustaining the cell environment in a matrix is rapid and convenient. Our experiment proved that photo-initiating GelMA hydrogel inside a well-designed microfluidic chip is a viable strategy for conducting co-culturing experiments as well as modeling invasion and migration events. This feature can also be used in experimental studies for drug delivery and drug dosage optimization studies on various diseases. In addition, by precisely controlling the fluid flow inside of the channels, studies on drug delivery speed and frequency can be conducted using this model. Using the developed model, the effects of drugs or various molecules on the cell’s encapsulated 3D environment can also be tested by using entities alongside the seeded cells or only with the medium at the selected channels.