Enhanced delivery of drugs to the brain

An antibody comprising a heavy chain and a light chain, wherein the heavy chain comprises a heavy chain acceptor framework of SEQ ID NO:

• 1;
• and wherein the light chain comprises a light chain acceptor framework of SEQ ID NO:
• 2, wherein the light chain CDR1, CDR2 and CDR3 at amino acids 28-34, 50-56, and 91-97 of SEQ ID NO:2, respectively, are replaced with the CDR1, CDR2 and CDR3 at amino acids 148-152, 170-172 and 208-216 of SEQ ID NO:4, respectively;
• and wherein the heavy chain CDR1, CDR2 and CDR3 at amino acids 31-35, 50-59, and 101-109 of SEQ ID NO:1, respectively, are replaced with the CDR1, CDR2 and CDR3 at amino acids 26-33, 51-58, and 97-110 of SEQ ID NO:4, respectively.