Quantification of non-reducing end glycan residual compounds for determining the presence, identity, or severity of a disease or condition

1. A method of determining the presence, identity, and/or severity of a disease or condition in an individual, where the disease or condition is associated with abnormal glycan biosynthesis, degradation, or accumulation, the method comprising:

(a) generating a biomarker comprising of one or more non-reducing end glycan residual compound(s), wherein the biomarker is generated by treating a population of glycans, in or isolated from a biological sample from the individual, with at least one digesting glycan enzyme(s), wherein prior to enzyme treatment, the biomarker is not present in abundance in samples from individuals with the disease or condition relative to individuals without the disease or condition;

(b) detecting the presence of and/or measuring the amount of the biomarker produced using an analytical instrument and displaying or recording the presence of or the measure of the biomarker produced; and

(c) correlating the presence of and/or the measure of the amount of the biomarker with the presence, identity, and/or severity of the disease or condition for determining the presence, identity, and/or severity of the disease or condition,

wherein the digesting glycan enzyme(s) are selected from the group consisting of glycosidases, sulfatases, phosphorylases, deacetylases, and sialidases, or combinations thereof.

2. The method of claim 1 , wherein the digesting glycan enzyme(s) is a glycosidase or a combination of glycosidases.

3. The method of claim 2 , wherein the glycosidase is an exo-glycosidase or a combination of exo-glycosidases.

4. The method of claim 3 , wherein the exo-glycosidase is a galactosidase, a glucuronidase, or a combination thereof.

5. The method of claim 1 , wherein the digesting glycan enzyme(s) is a glycosidase, an N-acetyl glycosidase, a hexosaminidase, or a combination thereof.

6. The method of claim 2 , wherein the glycosidase is a hexosaminidase, or a combination of hexosaminidases.

7. The method of claim 1 , wherein the digesting glycan enzyme(s) is a sulfatase, or a combination of sulfatases.

8. The method of claim 7 , wherein the sulfatase is a 4-O sulfatase, a 6-O sulfatase, or a combination thereof.

9. The method of claim 7 , wherein the sulfatase is a 6-O sulfatase, or a combination of 6-O sulfatases.

10. The method of claim 9 , wherein the 6-O sulfatase is a galactose 6-O-sulfatase, an N-acetyl galactosamine 6-O sulfatase, or a combination thereof.

11. The method of claim 1 , wherein the digesting glycan enzyme(s) is a phosphorylase, or a combination of phosphorylases.

12. The method of claim 1 , wherein the digesting glycan enzyme(s) is a deacetylase, or a combination of deacetylases.

13. The method of claim 1 , wherein the digesting glycan enzyme(s) is a sialidase, or a combination of sialidases.

14. The method of claim 1 , wherein the digesting glycan enzyme(s) is a chondroitin lyase, or a combination of chondroitin lyases.

15. The method of claim 1 , wherein the digesting glycan enzyme(s) are selected from the group consisting of a galactose 6-O-sulfatase, an N-acetyl galactosamine 6-O sulfatase, a galactosidase, and a hexosaminidase, or a combination thereof; and wherein the digesting glycan enzyme(s) liberates a glycan residual compound Gal and/or GalNAc.

16. The method of claim 15 , wherein the disease or condition is MPS IVA.

17. The method of claim 1 , wherein the digesting glycan enzyme(s) is a 6-O-sulfatase, or a combination of 6-O-sulfatases; and wherein the digesting glycan enzyme(s) is capable of desulfating 6-O-sulfated galactose and/or 6-O sulfated N-acetyl galactosamine residues; and wherein the digesting glycan enzyme(s) liberates a glycan residual compound sulfate.

18. The method of claim 17 , wherein the disease or condition is MPS IVA.

19. The method of claim 1 , wherein the digesting glycan enzyme(s) is a 4-O-sulfatase, or a combination of 4-O-sulfatases; wherein the digesting glycan enzyme(s) is capable of desulfating 4-O-sulfated N-acetyl galactosamine residues; and wherein the digesting glycan enzyme(s) liberates a glycan residual compound sulfate.

20. The method of claim 19 , wherein the disease or condition is MPS VI.

21. The method of claim 1 , wherein the biological sample is first treated with a 4-O-sulfatase digesting glycan enzyme, and then treated with a hexosaminidase digesting glycan enzyme, or a combination of hexosaminidases; wherein the 4-O-sulfatase is capable of desulfating 4-O-sulfated N-acetyl galactosamine residues; and wherein the hexosaminidase is capable of liberating a glycan residual compound N-acetyl galactosamine.

22. The method of claim 21 , wherein the disease or condition is MPS VI.

23. The method of claim 1 , wherein the digesting glycan enzyme(s) are selected from the group consisting of a 6-O-sulfatase, a galactosidase, a N-acetyl galactosidase, and a hexosaminidase, or a combination thereof; and wherein the digesting glycan enzyme(s) liberates a glycan residual compound sulfate, Gal-6-O sulfate, GalNAc-6-O sulfate, Gal, or GalNAc.

24. The method of claim 23 , wherein the disease or condition is MPS IVA.

25. The method of claim 1 , wherein the digesting glycan enzyme(s) are selected from the group consisting of a 4-O-sulfatase, and a chondroitin lyase, or a combination thereof; and wherein the digesting glycan enzyme(s) liberates a glycan residual compound GalNAc or GalNAc-4-O sulfate.

26. The method of claim 25 , wherein the disease or condition is MPS VI.

27. A method of determining the presence, identity, and/or severity of MPS IVA in an individual, the method comprising:

(a) generating a biomarker comprising of one or more non-reducing end glycan residual compound(s), wherein the biomarker is generated by treating a population of glycans, in or isolated from a biological sample from the individual, with at least one digesting glycan enzyme(s) selected from the group consisting of a galactose 6-O-sulfatase, an N-acetyl galactosamine 6-O sulfatase, a galactosidase, and a hexosaminidase, or a combination thereof, wherein prior to enzyme treatment, the biomarker is not present in abundance in samples from individuals with MPS IVA relative to individuals without MPS IVA;

(b) detecting the presence of and/or measuring the amount of the biomarker produced using an analytical instrument and displaying or recording the presence of or the measure of the biomarker produced; and

(c) correlating the presence of and/or the measure of the amount of the biomarker with the presence, identity, and/or severity of MPS IVA for determining the presence, identity, and/or severity of MPS IVA.

28. The method of claim 27 , wherein the digesting glycan enzyme(s) liberates a glycan residual compound Gal and/or GalNAc.

29. A method of determining the presence, identity, and/or severity of MPS VI in an individual, the method comprising:

(a) generating a biomarker comprising of one or more non-reducing end glycan residual compound(s), wherein the biomarker is generated by treating a population of glycans, in or isolated from a biological sample from the individual, with at least one digesting glycan enzyme(s) selected from the group consisting of a 4-O-sulfatase, and a chondroitin lyase, or a combination thereof, wherein prior to enzyme treatment, the biomarker is not present in abundance in samples from individuals with MPS VI relative to individuals without MPS VI;

(b) detecting the presence of and/or measuring the amount of the biomarker produced using an analytical instrument and displaying or recording the presence of or the measure of the biomarker produced; and

(c) correlating the presence of and/or the measure of the amount of the biomarker with the presence, identity, and/or severity of MPS VI for determining the presence, identity, and/or severity of MPS VI.

30. The method of claim 29 , wherein the digesting glycan enzyme(s) liberates a glycan residual compound GalNAc or GalNAc-4-O sulfate.