Agents directed against a cis rgma/neogenin interaction or lipid rafts and use of the same in methods of treatment

Abstract

Disclosed herein is an agent that modulates a cis interaction between Repulsive Guidance Molecule A (RGMa) and Neogenin or lipid rafts. Modulation by the agent may include blocking the cis interaction between RGMa and Neogenin and/or disrupting lipid rafts. In turn, this promotes neuronal cell survival and axon growth and/or regeneration. Also disclosed herein is a method of treating a disease in a subject in need thereof. The method may include administering the agent to the subject. Further disclosed herein is a method of identifying an agent that modulates the cis interaction between RGMa and Neogenin.

What is claimed is: 
     
         1 . An agent that promotes both (i) neuronal cell survival and (ii) axon growth and/or axon regeneration. 
     
     
         2 . The agent of  claim 1 , wherein the agent disrupts lipid rafts. 
     
     
         3 . The agent of  claim 1 , wherein the agent disrupts a cis interaction between Repulsive Guidance Molecule A (RGMa) and Neogenin. 
     
     
         4 . The agent of  claim 1 , wherein the agent is a peptide agent, an antibody, a cholesterol-lowering agent, or any combination thereof. 
     
     
         5 . The agent of  claim 4 , wherein the agent is the peptide agent. 
     
     
         6 . The agent of  claim 5 , wherein the peptide agent comprises an amino acid sequence selected from the group consisting of: an amino acid sequence comprising amino acids 1 to 383 of SEQ ID NO:1, an amino acid sequence comprising amino acids 1 to 417 of SEQ ID NO:11, an amino acid sequence as set forth in SEQ ID NO:2, an amino acid sequence as set forth in SEQ ID NO:3, an amino acid sequence as set forth in SEQ ID NO:4, an amino acid sequence as set forth in SEQ ID NO:7, an amino acid sequence as set forth in SEQ ID NO:8, an amino acid sequence as set forth in SEQ ID NO:9, an amino acid sequence as set forth in SEQ ID NO:10, and any combination thereof. 
     
     
         7 . The agent of  claim 6 , wherein the peptide agent comprises the amino acid sequence comprising amino acids 1 to 383 of SEQ ID NO:1. 
     
     
         8 . The agent of  claim 6 , wherein the peptide agent comprises the amino acid sequence as set forth in SEQ ID NO:2. 
     
     
         9 . The agent of  claim 6 , wherein the peptide agent comprises the amino acid sequence as set forth in SEQ ID NO:3. 
     
     
         10 . The agent of  claim 6 , wherein the peptide agent comprises the amino acid sequence as set forth in SEQ ID NO:4. 
     
     
         11 . The agent of  claim 6 , wherein the peptide agent comprises the amino acid sequence as set forth in SEQ ID NO:7. 
     
     
         12 . The agent of  claim 6 , wherein the peptide agent comprises the amino acid sequence as set forth in SEQ ID NO:8. 
     
     
         13 . The agent of  claim 6 , wherein the peptide agent comprises the amino acid sequence as set forth in SEQ ID NO:9. 
     
     
         14 . The agent of  claim 6 , wherein the peptide agent comprises the amino acid sequence as set forth in SEQ ID NO:10. 
     
     
         15 . The agent of  claim 6 , wherein the peptide agent disrupts a cis interaction between Repulsive Guidance Molecule A (RGMa) and Neogenin, thereby blocking recruitment of Neogenin to lipid rafts. 
     
     
         16 . The agent of  claim 4 , wherein the agent is the antibody. 
     
     
         17 . The agent of  claim 16 , wherein antibody specifically binds an amino acid sequence selected from the group consisting of: an amino acid sequence comprising amino acids 1 to 383 of SEQ ID NO:1, an amino acid sequence comprising amino acids 1 to 417 of SEQ ID NO:11, an amino acid sequence as set forth in SEQ ID NO:2, an amino acid sequence as set forth in SEQ ID NO:3, an amino acid sequence as set forth in SEQ ID NO:4, an amino acid sequence as set forth in SEQ ID NO:7, an amino acid sequence as set forth in SEQ ID NO:8, an amino acid sequence as set forth in SEQ ID NO:9, and an amino acid sequence as set forth in SEQ ID NO:10. 
     
     
         18 . The agent of  claim 17 , wherein the antibody specifically binds the amino acid sequence comprising amino acids 1 to 383 of SEQ ID NO:1. 
     
     
         19 . The agent of  claim 17 , wherein the antibody specifically binds the amino acid sequence as set forth in SEQ ID NO:2. 
     
     
         20 . The agent of  claim 17 , wherein the antibody specifically binds the amino acid sequence as set forth in SEQ ID NO:3. 
     
     
         21 . The agent of  claim 17 , wherein the antibody specifically binds the amino acid sequence as set forth in SEQ ID NO:4. 
     
     
         22 . The agent of  claim 17 , wherein the antibody specifically binds the amino acid sequence as set forth in SEQ ID NO:7. 
     
     
         23 . The agent of  claim 17 , wherein the antibody specifically binds the amino acid sequence as set forth in SEQ ID NO:8. 
     
     
         24 . The agent of  claim 17 , wherein the antibody specifically binds the amino acid sequence as set forth in SEQ ID NO:9. 
     
     
         25 . The agent of  claim 17 , wherein the antibody specifically binds the amino acid sequence as set forth in SEQ ID NO:10. 
     
     
         26 . The agent of  claim 17 , wherein the antibody disrupts a cis interaction between Repulsive Guidance Molecule A (RGMa) and Neogenin, thereby blocking recruitment of Neogenin to lipid rafts. 
     
     
         27 . The agent of  claim 4 , wherein the agent is the cholesterol-lowering agent. 
     
     
         28 . The agent of  claim 27 , wherein the cholesterol-lowering agent is selected from the group consisting of: methyl-β-cyclodextrin (MβCD), cholesterol oxidase (CO), AY-9944, a statin, a subtisilin/kexin type 9 (PCK9) inhibitor, nystatin, filipin, proprotein convertase, BM15.766, an alkylphospholipid analog, and any combination thereof. 
     
     
         29 . The agent of  claim 28 , wherein the cholesterol-lowering agent disrupts lipid rafts, thereby disrupting recruitment of Neogenin to lipid rafts. 
     
     
         30 . A method of treating a disease in a subject in need thereof, the method comprising administering the agent of  claim 1  to the subject. 
     
     
         31 . The method of  claim 30 , wherein the disease is selected from the group consisting of: retinitis pigmentosa, ischemia, multiple sclerosis, spinal cord injury, and optic nerve injury. 
     
     
         32 . The method of  claim 31 , wherein the ischemia is stroke. 
     
     
         33 . The method of  claim 30 , wherein the agent is a peptide agent, an antibody, a cholesterol-lowering agent, or any combination thereof. 
     
     
         34 . The method of  claim 33 , wherein the agent is the peptide agent and wherein the peptide agent comprises an amino acid sequence selected from the group consisting of: an amino acid sequence comprising amino acids 1 to 383 of SEQ ID NO:1, an amino acid sequence comprising amino acids 1 to 417 of SEQ ID NO:11, an amino acid sequence as set forth in SEQ ID NO:2, an amino acid sequence as set forth in SEQ ID NO:3, an amino acid sequence as set forth in SEQ ID NO:4, an amino acid sequence as set forth in SEQ ID NO:7, an amino acid sequence as set forth in SEQ ID NO:8, an amino acid sequence as set forth in SEQ ID NO:9, an amino acid sequence as set forth in SEQ ID NO:10, and any combination thereof. 
     
     
         35 . The method of  claim 33 , wherein the agent is the cholesterol-lowering agent and wherein the cholesterol-lowering agent is selected from the group consisting of: methyl-β-cyclodextrin (MβCD), cholesterol oxidase (CO), AY-9944, a statin, a subtisilin/kexin type 9 (PCK9) inhibitor, nystatin, filipin, proprotein convertase, BM15.766, an alkylphospholipid analog, and any combination thereof. 
     
     
         36 . The method of  claim 33 , wherein the agent is the antibody and wherein the antibody specifically binds an amino acid sequence selected from the group consisting of: an amino acid sequence comprising amino acids 1 to 383 of SEQ ID NO:1, an amino acid sequence comprising amino acids 1 to 417 of SEQ ID NO:11, an amino acid sequence as set forth in SEQ ID NO:2, an amino acid sequence as set forth in SEQ ID NO:3, an amino acid sequence as set forth in SEQ ID NO:4, and an amino acid sequence as set forth in SEQ ID NO:7. 
     
     
         37 . The method of  claim 30 , further comprising disrupting the cis interaction between RGMa and Neogenin. 
     
     
         38 . The method of  claim 30 , further comprising disrupting lipid rafts. 
     
     
         39 . The method of  claim 31 , wherein the disease is spinal cord injury and wherein the method further comprises restoring locomotor function in the subject. 
     
     
         40 . The method of  claim 31 , wherein the disease is retinitis pigmentosa and wherein the method further comprises promoting survival of photoreceptor cells in the subject. 
     
     
         41 . The method of  claim 32 , wherein the method further comprises reducing at least one of infarct volume, brain edema, or a combination thereof in the subject. 
     
     
         42 . A method of identifying an agent that modulates a cis interaction between Repulsive Guidance Molecule A (RGMa) and Neogenin, the method comprising:
 (a) forming a mixture comprising a RGM peptide and a Neogenin peptide, wherein the RGM peptide comprises an amino acid sequence selected from the group consisting of an amino acid sequence as set forth in SEQ ID NO:2, an amino acid sequence as set forth in SEQ ID NO:3, an amino acid sequence as set forth in SEQ ID NO:4, an amino acid sequence as set forth in SEQ ID NO:7, an amino acid sequence as set forth in SEQ ID NO:9, and an amino acid sequence as set forth in SEQ ID NO:10, and wherein the Neogenin peptide comprises an amino acid sequence selected from the group consisting of: an amino acid sequence comprising amino acids 1 to 383 of SEQ ID NO:1, an amino acid sequence comprising amino acids 1 to 417 of SEQ ID NO:11, and an amino acid sequence as set forth in SEQ ID NO:8;   (b) incubating the mixture in the presence of the agent; and   (c) detecting in the incubated mixture of step (b) a level of specific binding between the RGM peptide and the Neogenin peptide, wherein a difference in the detected level of specific binding of the RGM peptide to the Neogenin peptide in the presence of the agent relative to a level of specific binding of the RGM peptide to the Neogenin peptide in the absence of the agent indicates that agent modulates the cis interaction.   
     
     
         43 . The method of  claim 42 , wherein the agent is an antibody or an antibody fragment. 
     
     
         44 . The method of  claim 42 , wherein the RGM peptide is a RGMa peptide and is the amino acid sequence as set forth in SEQ ID NO:2. 
     
     
         45 . The method of  claim 42 , wherein the RGM peptide is a RGMa peptide and is the amino acid sequence as set forth in SEQ ID NO:3. 
     
     
         46 . The method of  claim 42 , wherein the RGM peptide is a RGMa peptide and is the amino acid sequence as set forth in SEQ ID NO:4. 
     
     
         47 . The method of  claim 42 , wherein the RGM peptide is a RGMa peptide and is the amino acid sequence as set forth in SEQ ID NO:7. 
     
     
         48 . The method of  claim 42 , wherein the RGM peptide is a RGMc peptide and is the amino acid sequence as set forth in SEQ ID NO:9. 
     
     
         49 . The method of  claim 42 , wherein the RGM peptide is a RGMa peptide and is the amino acid sequence as set forth in SEQ ID NO:10. 
     
     
         50 . The method of  claim 42 , wherein the Neogenin peptide is amino acids 1 to 383 of SEQ ID NO:1. 
     
     
         51 . The method of  claim 42 , wherein the Neogenin peptide is the amino acid sequence as set forth in SEQ ID NO:8. 
     
     
         52 . The method of  claim 42 , wherein modulation includes disrupting the cis interaction between RGMa and Neogenin. 
     
     
         53 . The method of  claim 52 , wherein if the detected level of specific binding of the RGM peptide to the Neogenin peptide in the presence of the agent is lower than the level of specific binding of the RGM peptide to the Neogenin peptide in the absence of the agent, then the agent disrupts the cis interaction. 
     
     
         54 . A peptide comprising an amino acid sequence having at least about 95% identity to an amino acid sequence comprising amino acids 1 to 383 of SEQ ID NO:1, wherein the peptide disrupts a cis interaction between Repulsive Guidance Molecule A (RGMa) and Neogenin. 
     
     
         55 . A peptide comprising an amino acid sequence having at least about 95% identity to an amino acid sequence as set forth in SEQ ID NO:2, wherein the peptide disrupts a cis interaction between Repulsive Guidance Molecule A (RGMa) and Neogenin. 
     
     
         56 . A peptide comprising an amino acid sequence having at least about 95% identity to an amino acid sequence as set forth in SEQID NO:3, wherein the peptide disrupts a cis interaction between Repulsive Guidance Molecule A (RGMa) and Neogenin. 
     
     
         57 . A peptide comprising an amino acid sequence having at least about 95% identity to an amino acid sequence as set forth in SEQ ID NO:4, wherein the peptide disrupts a cis interaction between Repulsive Guidance Molecule A (RGMa) and Neogenin. 
     
     
         58 . A peptide comprising an amino acid sequence having at least about 95% identity to an amino acid sequence as set forth in SEQ ID NO:7, wherein the peptide disrupts a cis interaction between Repulsive Guidance Molecule A (RGMa) and Neogenin. 
     
     
         59 . A peptide comprising an amino acid sequence having at least about 95% identity to an amino acid sequence as set forth in SEQ ID NO:8, wherein the peptide disrupts a cis interaction between Repulsive Guidance Molecule A (RGMa) and Neogenin. 
     
     
         60 . A peptide comprising an amino acid sequence having at least about 95% identity to an amino acid sequence as set forth in SEQ ID NO:9, wherein the peptide disrupts a cis interaction between Repulsive Guidance Molecule A (RGMa) and Neogenin. 
     
     
         61 . A peptide comprising an amino acid sequence having at least about 95% identity to an amino acid sequence as set forth in SEQ ID NO:10, wherein the peptide disrupts a cis interaction between Repulsive Guidance Molecule A (RGMa) and Neogenin. 
     
     
         62 . The agent of  claim 6 , wherein the peptide agent comprises the amino acid sequence comprising amino acids 1 to 417 of SEQ ID NO:11. 
     
     
         63 . The agent of  claim 17 , wherein the antibody specifically binds the amino acid sequence comprising amino acids 1 to 417 of SEQ ID NO:11. 
     
     
         64 . The method of  claim 42 , wherein the Neogenin peptide is amino acids 1 to 417 of SEQ ID NO:11. 
     
     
         65 . A peptide comprising an amino acid sequence having at least about 95% identity to an amino acid sequence comprising amino acids 1 to 417 of SEQ ID NO:11, wherein the peptide disrupts a cis interaction between Repulsive Guidance Molecule A (RGMa) and Neogenin.