Tomocube exposes how immune and cancer cells interact
A joint team from Tomocube and the Korea Advanced Institute of Science and Technology (KAIST) has exploited the rapid, label-free imaging and volumetric analysis of cell-to-cell interactions related to immuno-oncology for the first time.
Tomocube’s Holotomography (HT) microscope was exploited to study in 4D the interaction dynamics of T cells and their targets in the Immunological Synapse (IS).
Using a deep-learning network to interpret the tomographic images, they tracked CD19-positive K562 cells and CD19-specific Chimeric Antigen Receptor T cells (CAR-T19 cells), hailed in immune-oncology as the next-generation, personalized, anti-cancer treatment.
3D tomograms of the cells were acquired every 500 milliseconds to capture the refractive index (RI) and corresponding total protein density distributions before automated, real-time, three-dimensional analysis of the IS between the interacting cells was executed by the deep-learning network.
This automatic and quantitative spatiotemporal analyses of IS kinetics, together with morphological and biochemical parameters related to the total protein densities of immune cells, is set to provide new perspectives for immunological studies.
According to Aubrey Lambert, Chief Marketing Officer at Tomocube, many research teams are focused on the study of the Immunological Synapse (IS) in their bid to understand at the nano-scale how immune cells recognize pathogens and malignant cancer cells.
Although fluorescence-based techniques have proven useful in imaging this dynamically interacting junction between immune cells and their targets, photo-bleaching, photo-toxicity, and slow imaging limit their ability to address single-cell dynamic imaging successfully.
Label-free Immunological Synapse (IS) reconstruction and quantification of the IS formation kinetics of CAR-T cells: a reconstructed refractive index map is used as the input for the deep-learning model, which segments CART19 and K562-CD19 cells and defines the immunological synapse. The colour maps are based on the two-dimensional ranges of RI and the RI gradient. The 2D Projection shows the projection of 3D protein density distributions of the two cells with the Immunological synapse showing the surface protein densities of the cell-cell interface.
“Our powerful combination of label-free holotomography microscopy and deep learning-based automated analysis illuminates the 4D IS formation dynamics of CAR-T19 cells,” says Lambert. "However, the method is easily modified to study other areas in immunological research, ranging from TCR signalling pathways to cytotoxicity of innate immune cells."
“The next results, which are expected shortly, will highlight the correlative fluorescence imaging now available on the HT-2 microscope, improving the precision and accuracy of the technique and providing the chemical specificities necessary to elucidate the remaining questions about IS formation mechanisms,” he adds.