Fig. 4From: Challenges and strategies associated with CAR-T cell therapy in blood malignanciesTumor microenvironment. Immunosuppressive cells, including Treg, MDSCs, extracellular vesicles and TAMs, are present in the TME. They inhibit effector T cell function, enhance recruitment of Treg cells, and induce an immunosuppressive M2 phenotype by secreting cytokines such as IL-8, IL-6, IL-10, IL-35, and TGF-β.Back to article page