The contribution of automated cytometry in immuno-oncology.

Cancer immunotherapy has been a real revolution and has given many survival chances to several patients. However, the understanding of resistance to immunotherapy is still an unmet need in clinical practice. Monitoring of immune mechanisms could be a tool to better understand this phenomenon. FCM and CyTOF could be used in this field, since they allow the simultaneous analysis of several protein expressions pattern, thus possibly understanding the functions of several immune cell populations, such as T cells, and their interactions with tumor cells and tumor microenvironment. Furthermore, automated cytometry could be used to understand the interaction of drugs with their target through the analysis of receptor occupancy. Spectral overlap, however, could be a limit for multiple simultaneous analyses. Other possible limitations of these techniques are a low number of cells in samples and the need for viable cells (with the possible interference of cell debris). The lack of standardized protocols, and thus the difficult reproducibility, have been the major limit to their application in clinical practice, so international efforts have been made to get to shared guidelines. Ongoing trials are to answer to the possibility of clinical application of these techniques.