Fc receptor binding proteins

Abstract

This disclosure provides, inter alia, proteins that bind to FcRn, e.g., immunoglobulins that inhibit FcRn with high affinity and selectivity. The FcRn-binding proteins can be used to treat a variety of disorders including autoimmune disorders.

1 - 63 . (canceled) 
     
     
         64 : A method of detecting FcRn in a sample, the method comprising:
 contacting the sample with an antibody that binds to human FcRn;   detecting an interaction between the antibody and the FcRn if present; and   wherein the antibody comprises a heavy chain (HC) immunoglobulin variable domain sequence and a light chain (LC) immunoglobulin variable domain sequence, and wherein   the HC comprises:
 a HC CDR1 comprising the amino acid sequence EYAMG (SEQ ID NO:144) or VYAMG (SEQ ID NO:156), 
 a HC CDR2 comprising the amino acid sequence SIGSSGGQTKYADSVKG (SEQ ID NO:145) or SIGSSGGPTKYADSVKG (SEQ ID NO:157), and 
 a HC CDR3 comprising the amino acid sequence LSTGELY (SEQ ID NO:146), LSIRELV (SEQ ID NO:158), LSIVDSY (SEQ ID NO:164), LSLGDSY (SEQ ID NO:170), or, LAIGDSY (SEQ ID NO:176); and 
   the LC comprises:
 a LC CDR1 comprising the amino acid sequence TGTGSDVGSYNLVS (SEQ ID NO:141), 
 a LC CDR2 comprising the amino acid sequence GDSQRPS (SEQ ID NO:142), and 
 a LC CDR3 comprising the amino acid sequence CSYAGSGIYV (SEQ ID NO:143). 
   
     
     
         65 - 110 . (canceled) 
     
     
         111 : The method of  claim 64 , wherein the antibody further comprises a detectable label. 
     
     
         112 : A method of detecting FcRn in a subject, the method comprising:
 administering an antibody further comprises a detectable label, to a subject; and   detecting the label in the subject, and   wherein the antibody comprises a heavy chain (HC) immunoglobulin variable domain sequence and a light chain (LC) immunoglobulin variable domain sequence, and wherein   the HC comprises:
 a HC CDR1 comprising the amino acid sequence EYAMG (SEQ ID NO:144) or VYAMG (SEQ ID NO:156), 
 a HC CDR2 comprising the amino acid sequence SIGSSGGQTKYADSVKG (SEQ ID NO:145) or SIGSSGGPTKYADSVKG (SEQ ID NO:157), and 
 a HC CDR3 comprising the amino acid sequence LSTGELY (SEQ ID NO:146), LSIRELV (SEQ ID NO:158), LSIVDSY (SEQ ID NO:164), LSLGDSY (SEQ ID NO:170), or, LAIGDSY (SEQ ID NO:176); and 
   the LC comprises:
 a LC CDR1 comprising the amino acid sequence TGTGSDVGSYNLVS (SEQ ID NO:141), 
 a LC CDR2 comprising the amino acid sequence GDSQRPS (SEQ ID NO:142), and 
 a LC CDR3 comprising the amino acid sequence CSYAGSGIYV (SEQ ID NO:143). 
   
     
     
         113 : The method of  claim 112 , wherein the detecting comprises imaging the subject.