Understanding cancer and immune cell heterogeneity using microfluidics, dielectrophoresis, and conventional methods

Cell heterogeneity is characterized by the genetic variations, environmental differences, and reversible changes in cellular properties. Phenotypic and functional heterogeneity develops in cells within the same population. This heterogeneity is extensively studied and implemented in different fields, namely, molecular biology, genetics, immunology, cancer biology, cell biology, biochemistry, and biophysics. It is experimentally proven that cell heterogeneity inside the tumor enhances the invasive characteristics of the cancer cells. In this study, Glioblastoma cell line U87 and tumor associated macrophages as well as monocytes were investigated using different lab-on-chip devices, and conventional cell culture techniques. It is aimed to understand the heterogeneity of cells within a single population and direct and indirect culture of cancer and immune cells. Heterogeneity is quantified in population level using conventional cell culture techniques, while microfluidic device enabled to receive single cell level data, dielectrophoresis expanded the results by giving dielectric deformation and position of the single cells real time, continuously. Immunostaining experiments further enhanced heterogeneity by determining biomechanical properties of cells such as size, invasiveness, mesenchymal phenotype, macrophage polarization, immune cell plasticity in dynamic environment, and expression levels of Vimentin, E-Cadherin, CD68, CD80, CD163, CD11a, CD11b, and CD14. Batch culture assays and microfluidic tools together provided better insights about the behavior of cells. Both macrophage and glioma populations were highly heterogenous. Glioma cells exhibited higher migration rate and lower proliferation rate when there was paracrine signaling with macrophages. Existing lab-on-chip techniques must be developed to analyze thousands of cells and patient-specific samples