Imaging mass cytometry was used for direct visualization of platinum localization in tissue sections from tumor and normal tissues of cisplatin-treated mice bearing pancreas cancer patient-derived xenografts. This recently-developed technology enabled simultaneous detection of multiple markers to define cell lineage, DNA damage response, cell proliferation and functional state, providing a highly detailed view of drug incorporation in tumor and normal tissues at the cellular level. A striking and unanticipated finding was the extensive binding of platinum to collagen fibers in both tumor and normal mouse tissues. Time course experiments indicated the slow release of stroma-bound platinum, although it is currently unclear if released platinum retains biological activity. Imaging mass cytometry offers a unique window into the in vivo effects of platinum compounds, and it is likely that this can be extended into the clinic in order to optimize the use of this important class of agent.

We demonstrate the performance of a novel LA-ICP-MS system using a metal-doped PMMA film.

CyTOF® mass cytometry is a single-cell analysis platform that uses isotope-tagged antibodies to resolve 50-plus markers in a single tube without signal compensation, making CyTOF ideal for routine immunophenotyping. CyTOF XT™, the latest CyTOF system, features automated sample acquisition. Stained samples were acquired in parallel using the automated CyTOF XT system and manually, using the Helios™ system, to assess performance of the automated system. Multiple suspension mass cytometry staining workflows were evaluated. Population frequencies and resolution indices for markers were assessed by manual gating. There was no significant difference between population frequencies analyzed between the two CyTOF systems. On average, samples acquired on CyTOF XT resulted in greater resolution between positive and negative populations compared to Helios. The Maxpar® Direct™ Immune Profiling System, which comprises the Maxpar® Direct™ Immune Profiling Assay™ and Maxpar Pathsetter™ software, was also compared on the CyTOF XT and Helios systems. The Maxpar Direct Immune Profiling Assay includes a 30-marker panel in a dry, single-tube format for staining human whole blood or PBMC. Maxpar Pathsetter automates reporting of population statistics and stain assessments for the panel. Maxpar Pathsetter showed comparable population frequencies between the two CyTOF systems and improved staining assessment on CyTOF XT. Overall, these studies find that the CyTOF XT system generates better signal resolution than the Helios system. Automated acquisition by CyTOF XT enables researchers to accurately and reproducibly streamline human immunophenotyping. For Research Use Only. Not for use in diagnostic procedures.