Diagnosing and treating iga nephropathy

Abstract

Provided are methods of diagnosing IgA nephropathy in a subject. Optionally, the methods comprise isolating an IgG from the subject and determining whether the IgG binds to a galactose-deficient IgA1. Optionally, the methods comprise providing a biological sample from the subject and detecting in the sample a mutation in a IGH gene, wherein the mutation is in a nucleotide sequence encoding a complementarity determining region 3 (CDR3) of a IGH variable region. Optionally, the methods comprise determining a level of IgG specific for a galactose-deficient IgA1 in the subject. Also provided are methods of treating or reducing the risk of developing IgA nephropathy in a subject.

1 .- 50 . (canceled) 
     
     
         51 . A kit for performing an immunoassay, the kit comprising:
 (a) an isolated antibody specific for galactose-deficient IgA1; and   (b) a container.   
     
     
         52 . The kit of  claim 51 , further comprising an IgA1 specific antibody and/or an IgG specific antibody. 
     
     
         53 . The kit of  claim 51 , further comprising an assay substrate. 
     
     
         54 . The kit of  claim 53 , wherein the assay substrate comprises a membrane. 
     
     
         55 . The kit of  claim 51 , further comprising a control sample. 
     
     
         56 - 61 . (canceled) 
     
     
         62 . The kit of  claim 51 , wherein the antibody is specific for a galactose-deficient hinge-region O-linked glycan of IgA1