Insulin-like growth factor 1 receptor-specific antibodies and uses thereof
The blood-brain barrier (BBB) prevents transport of molecules larger than 500 Dal tons from blood to brain. Receptor-mediated transcytosis (RMT) facilitates transport across the BBB of specific molecules that bind receptors on brain endothelial cells that form the BBB. An insulin-like growth factor 1 receptor (IGF 1R)-binding antibody or fragment thereof is identified that transmigrates the BBB by RMT. The antibody or fragment is used to deliver a cargo molecule across the BBB, wherein the cargo molecule may be a therapeutic or detectable agent. The antibody is a camelid VHH, prepared by immunizing a llama with a 933-amino acid IGF 1R polypeptide. Humanized forms of the camelid VHH are also generated.
1. An isolated or purified single domain antibody or antigen-binding fragment thereof, comprising
a complementarity determining region (CDR) 1 sequence of GGTVSPTA (SEQ ID NO:1);
a CDR2 sequence of ITWSRGTT (SEQ ID NO:2); and
a CDR3 sequence of AASTFLRILPEESAYTY (SEQ ID NO:3),
wherein the single domain antibody or antigen-binding fragment thereof is specific for Insulin-Like Growth Factor 1 Receptor (IGF1R).
2. The isolated or purified single domain antibody or antigen-binding fragment thereof of claim 1 , comprising the sequence
X 1 VX 2 LX 3 ESGGGLVQX 4 GGSLRLSCX 5 X 6 SGGTVSPTAMGWX 7 RQAPGKX 8 X 9 EX 10 VX 11 HITWSRGTTRX 12 ASSVKX 13 RFTISRDX 14 X 15 KNTX 16 YLQMNSLX 17 X 18 EDTAV YYCAASTFLRILPEESAYTYWGQGT X 19 VTVSS (SEQ ID NO:4), where X 1 is E or Q; X 2 is K or Q; X 3 is V or E; X 4 is A or P; X 5 is A or E; X 6 is V or A; X 7 is V or F; X 8 is G or E; X 9 is L or R; X 10 is F or W; X 11 is G or S; X 12 is V or Y; X 13 is D or G; X 14 is N or S; X 15 is A or S; X 16 is L or V; X 17 is K or R; X 18 is A or S; and X 19 is L or Q.
3. The isolated or purified single domain antibody or antigen-binding fragment thereof of claim 1 comprising a sequence selected from the group consisting of:
(SEQ ID NO: 5)
QVKLEESGGGLVQAGGSLRLSCEVSGGTVSPTAMGWFRQAPGKEREFVGH
ITWSRGTTRVASSVKDRFTISRDSAKNTVYLQMNSLKSEDTAVYYCAAST
FLRILPEESAYTYWGQGTQVTVSS;
(SEQ ID NO: 6)
QVQLVESGGGLVQPGGSLRLSCAVSGGTVSPTAMGWVRQAPGKGLEWVGH
ITWSRGTTRYASSVKGRFTISRDNSKNTVYLQMNSLRAEDTAVYYCAAST
FLRILPEESAYTYWGQGTLVTVSS;
(SEQ ID NO: 7)
QVQLVESGGGLVQPGGSLRLSCAVSGGTVSPTAMGWFRQAPGKGLEFVGH
ITWSRGTTRYASSVKGRFTISRDNSKNTVYLQMNSLRAEDTAVYYCAAST
FLRILPEESAYTYWGQGTLVTVSS;
(SEQ ID NO: 8)
QVQLVESGGGLVQPGGSLRLSCAVSGGTVSPTAMGWFRQAPGKGLEFVGH
ITWSRGTTRYASSVKGRFTISRDSSKNTVYLQMNSLRAEDTAVYYCAAST
FLRILPEESAYTYWGQGTLVTVSS; and
(SEQ ID NO: 9)
QVQLVESGGGLVQPGGSLRLSCAVSGGTVSPTAMGWFRQAPGKEREFVGH
ITWSRGTTRYASSVKGRFTISRDSSKNTVYLQMNSLRAEDTAVYYCAAST
FLRILPEESAYTYWGQGTLVTVSS.
4. The isolated or purified single domain antibody or antigen-binding fragment thereof of claim 1 , wherein the single domain antibody is of camelid origin.
5. The isolated or purified single domain antibody or antigen-binding fragment thereof of claim 1 , wherein the single domain antibody or antigen-binding fragment thereof is in a multivalent display format.
6. The isolated or purified single domain antibody or antigen-binding fragment thereof of claim 5 , wherein the single domain antibody or antigen-binding fragment thereof is linked to a Fc fragment.
7. The isolated or purified single domain antibody or antigen-binding fragment thereof of claim 1 , wherein the single domain antibody or antigen-binding fragment thereof is immobilized onto a surface.
8. The isolated or purified single domain antibody or antigen-binding fragment thereof of claim 1 , wherein the single domain antibody or antigen-binding fragment thereof is linked to a cargo molecule.
9. The isolated or purified single domain antibody or antigen-binding fragment thereof of claim 8 , wherein the cargo molecule has a molecular weight in the range of about 1 kD to about 200 kDa.
10. The isolated or purified single domain antibody or antigen-binding fragment thereof of claim 8 , wherein the cargo molecule is a detectable agent, a therapeutic, a peptide, a growth factor, a cytokine, a receptor trap, a chemical compound, a carbohydrate moiety, an enzyme, an antibody or fragment thereof, a DNA-based molecule, a viral vector, or a cytotoxic agent; one or more liposomes or nanocarriers loaded with a detectable agent, a therapeutic, a peptide, an enzyme, an antibody or fragment thereof, a DNA-based molecule, a viral vector, or a cytotoxic agent; or one or more nanoparticle, nanowire, nanotube, or quantum dots.
11. A composition comprising one or more than one isolated or purified single domain antibody or antigen-binding fragment thereof of claim 1 and a pharmaceutically-acceptable carrier, diluent, or excipient.