Abstract

Isolation of Sub-populations of Prostate Cancer Cells Using Inertial Microfluidics

Ian Papautsky, Professor of Bioengineering, Co-Director, NSF Center for Advanced Design & Manufacturing of Integrated Microfluidics, University of Illinois at Chicago

Inertial microfluidics is receiving considerable attention for applications in cell separation and liquid biopsy. Previously, our group introduced spiral inertial microfluidic (iMF) devices that couple Dean force with inertial migration for high-throughput cell separations. Here, we modify our spiral iMF device to isolate sub-population of two circulating tumor cell (CTC)-like cell lines obtained from biopsy specimens of patients with high-grade (Gleason score 9) prostate cancer. The iMF device, its outlet design, and operational parameters (1.3mL/min flowrate) were optimized to obtain high viability of separated cells (determined by counts and proliferation assays). The isolated HPET (Human Prostate Epithelial/hTERT) cells are not metastatic in-vivo, while HuSCL (Human Stem Cell-Like) cells are. Sphere-formation assay was used to assess “stemness” of the isolated cells, and led us to conclude that the larger (>18µm) and the smaller (14-17µm) cell sub-populations form distinct spheres. This finding suggests that cell size is a marker for the “stemness”, but also of the sorted cells being different sub-populations of the sorted cell-lines. This work also successfully demonstrates the use of an iMF device as a laboratory tool for sorting sub-populations of CTCs, and conclusively shows that the effects of fluidic shear on cell viability, functionality and “stemness” are negligible.