Laser transfer for circulating tumor cell isolation in liquid biopsy

• Published in: International journal of bioprinting 2023-01, Vol.9 (4), p.720-720
• Main Authors: Molpeceres, Carlos, Ramos-Medina, Rocio, Marquez, Andres, Romero, Paula, Gomez-Fontela, Miguel, Candorcio-Simon, Rocío, Muñoz, Andres, Lauzurica, Sara, Del Monte-Millan, Maria, Morales, Miguel, Muñoz-Martin, David, Lopez-Tarruella, Sara, Massarrah, Tatiana, Martin, Miguel
• Format: Article
• Language: English
• ISSN: 2424-7723; 2424-8002
• DOI: 10.18063/ijb.720

75Cancer research has found in the recent years a formidable ally in liquid biopsy, a noninvasive technique that allows the study of circulating tumor cells (CTCs) and biomolecules involved in the dynamics of cancer spread like cell-free nucleid acids or tumor-derived extracellular vesicles. However, single-cell isolation of CTCs with high viability for further genetic, phenotypic, and morphological characterization remains a challenge. We present a new approach for single CTC isolation in enriched blood samples using a liquid laser transfer (LLT) process, adapted from standard laser direct write techniques. In order to completely preserve the cells from direct laser irradiation, we used an ultraviolet laser to produce a blister-actuated laser-induced forward transfer process (BA-LIFT). Using a plasma-treated polyimide layer for blister generation, we completely shield the sample from the incident laser beam. The optical transparency of the polyimide allows direct cell targeting using a simplified optical setup, in which the laser irradiation module, standard imaging, and fluorescence imaging share a common optical path. Peripheral blood mononuclear cells (PBMCs) were identified by fluorescent markers, while target cancer cells remained unstained. As a proof of concept, we were able to isolate single MDA-MB-231 cancer cells using this negative selection process. Unstained target cells were isolated and culture while their DNA was sent for single-cell sequencing (SCS). Our approach appears to be an effective approach to isolate single CTCs, preserving cell characteristics in terms of cell viability and potential for further SCS.