Category: Cellular Technologies
Immunotherapy against cancer has proven clinical efficacy and tremendous potential in multiple tumor entities. Syngeneic mouse tumor models represent the gold standard to analyze effects of immunotherapy due to their fully competent immune-repertoire. However, the amount and composition of tumor infiltrating leukocytes (TIL) is highly variable, complicating the targeted analysis of subpopulations. In particular, small subpopulations cannot be analyzed properly but may be lost in the background noise.
We have established an automated workflow combining tissue dissociation with TIL specific isolation to improve and accelerate downstream analysis. Tumor dissociation was automated using the gentleMACS™ Octo Dissociator and optimized for epitope conservation to overcome bias in immune-phenotyping caused by dissociation with aggressive of impure enzymes. Next, isolation of TIL was improved by developing a new CD45-specific enrichment reagent for the magnetic cell sorting (MACS) based isolation directly from dissociated tumor tissue. To validate this method, we used syngeneic mouse tumors derived by injecting B16.F10 tumor cell lines. Using a manual separation system, TIL were enriched from under 4% to purities above 80% at high yields above 95%. To address the need of parallelization and automation for sample processing in large cohort sizes used in in vivo studies, a fully automated version of the MultiMACS™ Cell24 Separator was developed by integrating the instrument in a liquid handling robotic platform. This new system, the MultiMACS™ X, can process 24 cell separations in parallel with minimal hands-on time. Importantly, while the TIL enrichment significantly reduced the time and reagent costs in immune subset analysis, the composition of infiltrating immune cells was not affected, excluding the risk of introducing a bias by this method.
Taken together, we have developed an automated workflow for the isolation of TIL from mouse tumors reducing time and costs of downstream analysis while standardizing and enhancing the detection and quantification of immune cell subpopulations.
Lotta Raety– Product Manager, Miltenyi Biotec Gmbh, Bergisch Gladbach, Nordrhein-Westfalen, Germany
Miltenyi Biotec Gmbh
Bergisch Gladbach, Nordrhein-Westfalen, Germany
With a background in biotechnology and molecular biology, I joined Miltenyi Biotec as Product Manager for cell separation in 2016. My focus is on automation, and our vision is to supply every laboratory with the best solution for their cell workflow, regardless of size, throughput or sample type - for every step from sample preparation to analysis and culture.