title: A microfluidic Transwell to study chemotaxis.
abstract: Chemotaxis is typically studied in vitro using commercially available products such as the Transwell® in which cells migrate through a porous membrane in response to one or more clearly defined chemotactic stimuli. Despite its widespread use, the Transwell assay suffers from being largely an endpoint assay, with built-in errors due to inconsistent pore size and human sampling. In this study, we report a microfluidic chemotactic chip that provides real-time monitoring, consistent paths for cell migration, and easy on-chip staining for quantifying migration. To compare its performance with that of a traditional Transwell chamber, we investigate the chemotactic response of MDA-MB-231 1833 metastatic breast cancer cells to epidermal growth factor (EGF). The results show that while both platforms were able to detect a chemotactic response, we observed a dose-dependent response of breast cancer cells towards EGF with low non-specific migration using the microfluidic platform, whereas we observed a dose-independent response of breast cancer cells towards EGF with high levels of non-specific migration using the commercially available Transwell.The microfluidic platform also allowed EGF-dependent chemotactic responses to be observed 24h, a substantially longer window than seen with the Transwell. Thus the performance of our microfluidic platform revealed phenomena that were not detected in the Transwell under the conditions tested.
authors.affiliation: Department of Biomedical Engineering, Boston University, MA 02215, USA.
authors.forename: Chentian
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Department of Biomedical Engineering, Boston University, MA 02215, USA.
authors.forename: Maria P
authors.initials: MP
authors.lastname: Barrios
authors.affiliation: Department of Dermatology, Boston University School of Medicine, MA 02118, USA.
authors.forename: Rhoda M
authors.initials: RM
authors.lastname: Alani
authors.affiliation: Department of Biomedical Engineering, Boston University, MA 02215, USA; Center for Nanoscience and Nanobiotechnology, Boston University, Boston, MA 02215, USA.
authors.forename: Mario
authors.initials: M
authors.lastname: Cabodi
authors.affiliation: Department of Biomedical Engineering, Boston University, MA 02215, USA; Center for Nanoscience and Nanobiotechnology, Boston University, Boston, MA 02215, USA; Division of Materials Science & Engineering, Boston University, Boston, MA 02215, USA. Electronic address: jywong@bu.edu.
authors.forename: Joyce Y
authors.initials: JY
authors.lastname: Wong
mesh_terms: D018929:Cell Culture Techniques; D045744:Cell Line, Tumor; D002633:Chemotaxis; D004815:Epidermal Growth Factor / Q000502:physiology; D006801:Humans; D056656:Lab-On-A-Chip Devices
chemical_list: D004815:Epidermal Growth Factor
keywords: Breast cancer; Cell migration; Chemotaxis; EGF; Microfluidics; Transwell