University of Toronto spin-out DVS Sciences raised $14.6 million in a Series A round of financing with institutional investors. The funds will be used to speed commercial manufacturing scale-up of the firm’s flagship CyTYOF®-MAXPAR®.
DVS claims the CyTOF Mass Cytometer is the first inorganic mass spectrometer specifically designed for use for multiparametric single-cell analysis. It uses atomic mass spectrometry to allow the independent detection of metal-labeled antibodies based on currently available MAXPAR kits and two DNA intercalators. The firm says the CyTOF technology will potentially enable analysis of up to 100 stable isotope labels in a single sample.
“The complete solution comprises a high-throughput mass cytometer for individual cell analysis, CyTOF, and a suite of MAXPAR reagents, which include stable-isotope-tagged antibodies,” explains Andrew Schwab, managing partner at investment firm 5AM Ventures. “The CyTOF technology eliminates the inherent spectral overlap issues and enables quantative, highly multibiomarker analysis for scientific research, with potential applications in clinical trials and personalized medicine."
The CyTOF and MAXPAR technologies were originally developed by scientists at MDS Sciex (now AB Sciex) who subsequently moved to the University of Toronto to further develop the platform. All the resulting IP has been licensed to DVS Sciences.
The CyTOF workflow starts with the introduction of individual cells stained with metal-conjugated antibodies and metallointercalators into an Inductively Coupled Plasma, were they are atomized and ionized. The atomic ions are then extracted into the ion optics and time-of-flight regions where they are separated by mass and counted.
The elemental signature of the cell includes the element tags introduced with the antibodies and metallointercalators. The presence of the metal tag indicates that the antibody found and bound the target biomarker, and the intensity of the signal is directly proportional to the number of antibodies bound per cell (ABC).
The elemental composition of each cell is separately analyzed. DVS claims that in a typical cell-analysis experiment, four minutes of raw data collection is sufficient for analysis of 100,000 cells independent of the number of metal tags (one or all 33).
The firm offers MAXPAR antibody or intracellular protein labeling reagent kits for 33 different metals. The kits utilize a traditional approach of adding a metal tag using disulfide reduction (typically in the Fc region of the antibody) through a maleimide linker. DVS says the labeling methods are simple and can be completed in 2.5 hours; labeled antibodies are then stable for approximately six months after preparation.