Method and compositions for cellular immunotherapy

A nucleic acid encoding a chimeric receptor comprising:

• a) a polynucleotide encoding a ligand binding domain comprising the nucleotide sequence of residues 2150 to 2875 set forth in SEQ ID NO:54, wherein the ligand binding domain specifically binds to or interacts with CD171;
• b) a polynucleotide encoding a polypeptide spacer comprising the amino acid sequence set forth in SEQ ID NO:01, and wherein the spacer has a length greater than or equal to 12 and less than or equal to 119 consecutive amino acids;
• c) a polynucleotide encoding a transmembrane domain;
• and
• d) a polynucleotide encoding an intracellular signaling domain;
• wherein the chimeric receptor comprises an increased in vivo activity for a survival rate of a subject having a neuroblastoma and for neuroblastoma regression in the subject compared to an anti-CD171 chimeric receptor comprising a spacer having a length greater than 119 consecutive amino acids.