Burwell, A., Kasler, A., Bshara-Corson, S., Tiemann, T., Murray, C. “ Single Cell Cytokine Profiling Using Ferrologix' MagnetoSPOT Platform” Annual Conference of the Society for Laboratory Automation and Screening. February 27, 2023. San Diego, CA, USA.
Cell secretion analysis tools, including ELISA, ELISPOT, Bead Multiplexed ELISAs, microfluidic platforms, and flow cytometry analysis kits, have greatly contributed to precision medicine sectors, including oncology, drug discovery, and cellular therapeutics. These platforms
have enabled researchers to quantify cell-to-cell interactions, and cellular responses to external stimuli, and develop functional assays for complex biologics such as CAR T cell therapies. However, while current cell secretion assays provide valuable insights, they have several limitations.
One of the most commonly used cell secretion assays is well-plate-based ELISAs. While they are scalable and automation-compatible, they are limited to reporting sample concentrations from aggregate populations and are unable to measure individual cell activity. EliSPOT assays are similar in that they are scalable while also being able to measure single-cell secretions, however, they lack the ability to measure multiple analytes. using Single-cell secretion assays like Fluorospot, Berkeley Lights’ Beacon Optofluidic System & Isoplexis’ Isolight can also quantify secretions with single-cell resolution. However, these platforms have inherent tradeoffs between single -cell resolution, cost, and total cell throughput. The current technology gap confirms there is a need for technology that can actively observe and measure individual cellular activity while retaining scalability in an automation-friendly SBS-well plate format.
Ferrologix has developed a highly parallelized micromagnetic platform, called MagnetoSPOT, that self-assembles single cells for interrogating single-cell cytokine secretion profiles. Using micromagnet grids integrated into an SBS well plate, the MagnetoSPOT platform pixelates magnetically tagged cells in highly ordered arrays. Cytokine secretion profiles from single cells can be measured via co-localization with commercially available cytokine-capture beads followed by fluorescence quantification using high-content imaging. MagnetoSPOT’s high parallelization within a well plate format is a novel feature that enables higher throughput compared to other single-cell cytokine platforms (~5600 cells/well or >500k cells per plate).
In a split sample comparison, human CD14+ monocytes were stimulated with LPS and assayed for TNF-α secretion via MagnetoSPOT and a flow cytometry-based single-cell ELISA kit (Miltenyi). CD14+ cells were seeded onto MagnetoSPOT arrays, which demonstrated that greater than or equal to 90% of target cells were pixelated and distributed to individual micromagnetic pillars, allowing for single-cell resolution. Both assays were treated under the same conditions and showed statistically identical results (P-value >= 0.05) between the percent of secreting cells. These key performance indicators show that the MagnetoSPOT ELISA can obtain data that is consistent with commercially available gold standard products
In conclusion, Ferrologix’s MagnetoSPOT platform represents a novel and disruptive cell analysis platform that can be readily integrated into lab automation workflows. Its ability to self-assemble single cells into organized arrays and measure cytokine secretion profiles with single-cell resolution demonstrates that the MagnetoSPOT platform offers an automatable solution to the limitations of current cell secretion assays.