CCL2 and diffuse midline glioma: An additional phase I clinical trial (NCT03500991) conducted in a group of young people and children with refractory or recurrent Central Nervous System (CNS) tumors, including diffuse midline gliomas, demonstrated that iterative local HER2 CAR- T cell administration induced increased secretion of chemokines like C-C Motif Chemokine Ligand 2 (CCL2) and C-X-C motif chemokine ligand 10 (CXCL10) in the cerebrospinal fluid with no CAR-T cell dose-related toxicity [49].