Miox antibody and assay
The invention relates to compositions and methods for detecting renal injury in a subject, such as proximal tubular injury associated with acute kidney injury.
1. An isolated antibody, wherein the antibody specifically binds myo-inositol oxygenase (MIOX) and the heavy chain comprises the amino acid sequences of SEQ ID NOs: 4, 5, and 6, and the light chain comprises the amino acid sequences of SEQ ID NOs: 1, 2, and 3; or the heavy chain comprises the amino acid sequences of SEQ ID NOs: 10, 11, and 12, and the light chain comprises the amino acid sequences of SEQ ID NOs: 7, 8 and 9.
2. The isolated antibody of claim 1 , wherein the antibody comprises an amino acid sequence selected from the group consisting of SEQ ID NO:14 and SEQ ID NO:16.
3. The isolated antibody of claim 1 , wherein the antibody comprises an amino acid sequence selected from the group consisting of SEQ ID NO:13 and SEQ ID NO:15.
4. The isolated antibody of claim 1 , wherein the antibody is encoded by a nucleic acid sequence comprising a nucleic acid sequence selected from the group consisting of SEQ ID NO:17, SEQ ID NO:18, SEQ ID NO:19, and SEQ ID NO:20.
5. The isolated antibody of claim 1 , wherein the antibody is selected from the group consisting of a single-chain antibody, an antibody fragment, a chimeric antibody, or a humanized antibody.
6. A method for measuring the amount of MIOX in a biological sample, the method comprising (i) obtaining a sample of biological fluid from a subject; and (ii) measuring the amount of MIOX in the sample by immunoassay comprising at least one isolated antibody of claim 1 .
7. The method of claim 6 , wherein the biological sample is a biological fluid selected from the group consisting of blood, plasma, serum and urine.
8. The method of claim 6 , wherein measuring the amount of MIOX in the sample by immunoassay comprises a capture antibody and a capping antibody that specifically binds MIOX.
9. The method of claim 8 , wherein the capture antibody comprises a heavy chain comprising the amino acid sequences of SEQ ID NOs: 4, 5, and 6, and a light chain comprising the amino acid sequences of SEQ ID NOs: 1, 2, and 3, and the capping antibody comprises a heavy chain comprising the amino acid sequences of SEQ ID NOs: 10, 11, and 12, and a light chain comprising the amino acid sequences of SEQ ID NOs: 7, 8, and 9.
10. The method of claim 8 , wherein the capture antibody comprises a heavy chain comprising the amino acid sequences of SEQ ID NOs: 10, 11, and 12, and a light chain comprising the amino acid sequences of SEQ ID NOs: 7, 8, and 9, and the capping antibody comprises a heavy chain comprising the amino acid sequences of SEQ ID NOs: 4, 5, and 6, and a light chain comprising the amino acid sequences of SEQ ID NOs: 1, 2, and 3.
11. A method for detecting renal injury in a subject, the method comprising (i) obtaining a biological sample from a subject; (ii) measuring the amount of MIOX in the sample by immunoassay using at least one isolated antibody of claim 6 ; and (iii) comparing the amount of MIOX in the sample to a reference value, wherein a greater amount of MIOX in the sample compared to the reference value indicates renal injury in the subject.
12. The method of claim 11 , wherein the renal injury is directly or indirectly associated with proximal tubular injury.
13. The method of claim 12 , wherein the proximal tubular injury is directly or indirectly associated with proximal tubular cell damage.
14. The method of claim 11 , wherein the biological sample is a biological fluid selected from the group consisting of blood, plasma, serum and urine.
15. The method of claim 11 , wherein measuring the amount of MIOX in the sample by immunoassay comprises a capture antibody and a capping antibody that specifically binds MIOX.
16. The method of claim 15 , wherein the capture antibody comprises a heavy chain comprising the amino acid sequences of SEQ ID NOs: 4, 5, and 6, and a light chain comprising the amino acid sequences of SEQ ID NOs: 1, 2, and 3, and the capping antibody comprises a heavy chain comprising the amino acid sequences of SEQ ID NOs: 10, 11, and 12, and a light chain comprising the amino acid sequences of SEQ ID NOs: 7, 8, and 9.
17. The method of claim 15 , wherein the capture antibody comprises a heavy chain comprising the amino acid sequences of SEQ ID NOs: 10, 11, and 12, and a light chain comprising the amino acid sequences of SEQ ID NOs: 7, 8, and 9, and the capping antibody comprises a heavy chain comprising the amino acid sequences of SEQ ID NOs: 4, 5, and 6, and a light chain comprising the amino acid sequences of SEQ ID NOs: 1, 2, and 3.