title: Affinity Versus Label-Free Isolation of Circulating Tumor Cells: Who Wins?
abstract: The study of circulating tumor cells (CTCs) has been made possible by many technological advances in their isolation. Their isolation has seen many fronts, but each technology brings forth a new set of challenges to overcome. Microfluidics has been a key player in the capture of CTCs and their downstream analysis, with the aim of shedding light into their clinical application in cancer and metastasis. Researchers have taken diverging paths to isolate such cells from blood, ranging from affinity-based isolation targeting surface antigens expressed on CTCs, to label-free isolation taking advantage of the size differences between CTCs and other blood cells. For both major groups, many microfluidic technologies have reported high sensitivity and specificity for capturing CTCs. However, the question remains as to the superiority among these two isolation techniques, specifically to identify different CTC populations. This review highlights the key aspects of affinity and label-free microfluidic CTC technologies, and discusses which of these two would be the highest benefactor for the study of CTCs.
authors.affiliation: Department of Chemical Engineering, University of Michigan, 3074 H.H. Dow, 2300 Hayward Street Ann Arbor, MI, 48109, USA.|Biointerfaces Institute (BI), University of Michigan, North Campus Research Complex 2800 Plymouth Road, Ann Arbor, MI, 48109, USA.|Translational Oncology Program (TOP), University of Michigan, Ann Arbor, MI, 48109, USA.
authors.forename: Vasudha
authors.initials: V
authors.lastname: Murlidhar
authors.affiliation: Department of Chemical Engineering, University of Michigan, 3074 H.H. Dow, 2300 Hayward Street Ann Arbor, MI, 48109, USA.|Biointerfaces Institute (BI), University of Michigan, North Campus Research Complex 2800 Plymouth Road, Ann Arbor, MI, 48109, USA.|Translational Oncology Program (TOP), University of Michigan, Ann Arbor, MI, 48109, USA.
authors.forename: Lianette
authors.initials: L
authors.lastname: Rivera-Báez
authors.affiliation: Department of Chemical Engineering, University of Michigan, 3074 H.H. Dow, 2300 Hayward Street Ann Arbor, MI, 48109, USA.|Biointerfaces Institute (BI), University of Michigan, North Campus Research Complex 2800 Plymouth Road, Ann Arbor, MI, 48109, USA.|Translational Oncology Program (TOP), University of Michigan, Ann Arbor, MI, 48109, USA.
authors.forename: Sunitha
authors.initials: S
authors.lastname: Nagrath
mesh_terms: D000818:Animals; D014408:Biomarkers, Tumor / Q000378:metabolism; D002469:Cell Separation / Q000379:methods*; D006801:Humans; D044085:Microfluidics; D009360:Neoplastic Cells, Circulating / Q000473:pathology*; D013194:Staining and Labeling
chemical_list: D014408:Biomarkers, Tumor
keywords: affinity isolation; circulating tumor cells (CTCs); label-free isolation; microfluidics