CD274 and neoplasm: Flow cytometry is indispensable when dealing with heterotypic cultures for the study of different cell types and sub-populations, such as the identification and characterisation of M1 and M2 TAMs (e.g., through CD64 and CD206 staining, respectively) or CSC markers (e.g., CD133) and the study of specific oncogenic markers (e.g., PDL-1-positive tumour cells) (Evans et al., 2021; Sumkhemthong et al., 2021; Sulimanov et al., 2023).