Table 2.

Different strategies to improve CAR T cell trafficking in solid tumors.

Strategies	Mechanism of actions	Examples
Chemokine receptors expression on CAR T cells	Improved CAR T cell recruitment and migration	CCR2b, CCR4 (CCL17 receptor), CCL2, CCL17 and C-X-C motif chemokine receptor
Armed oncolytic adenovirus	Increase CAR T cell survival	Oncolytic virus engineered to express CCL5 and interleukin 15.
Engineered CAR T cells to secrete heparanase	Increase CAR T cell penetration into tumor cells	Degrade the extracellular matrix
Local delivery of CAR T cells	Direct delivery of CAR T cells into tumor site	Catheter infusion, intracranial, delivery, intracavitary, intraventricular and localized infusion through the hepatic artery

CAR, Chimeric antigen receptor; CCR, C-C chemokine receptor type; CCL, C-C motif chemokine ligand;