T cell activation is a critical step in the adaptive immune response. Studying the mechanisms of T cell activation is an important part of modern immunology research and in vitro activation is a requirement for cell therapy drug development programs. However, current methods to isolate activated T cells require labeling with T-cell markers (e.g. CD8) and key extracellular molecular activation indicators (such as CD38, CD45RO, and HLA-DR) with fluorescently tagged antibodies; a process that can interfere with downstream R&D assays and requires label removal in cell therapy development. The VisionSort platform enables label-free sorting of T cells, giving investigators and drug developers activated T cells, untouched by external labels, for use in downstream assays and cell therapy development programs. In this research collaboration with the University of Tokyo, we use a mouse model of T cell activation to show how the VisionSort platform can be used to achieve label-free sorting of activated cells.