PDCD1 and neuroblastoma: NB, Neuroblastoma; ADCC, antibody-dependent cell-mediated cytotoxicity; CDC: Complement dependent cytotoxicity; PD1, Programmed Cell Death; PD-L1, Programmed Cell Death Ligand 1; CART Cells: Chimeric Antigen Receptor T cells; CTLA4, Cytotoxic T-lymphocyte associated protein 4; IL1/2, Interleukin 1/2; DNA: Deoxyribonucleic acid.