Fc VARIANTS WITH ALTERED BINDING TO FcRn

Abstract

The present application relates to a variant Fc region comprising at least one modification relative to a wild-type human Fc region, where the modification selected from the group consisting of 434S, 252Y/428L, 252Y/434S, and 428L/434S, and the numbering is according to the EU index.

1 .- 19 . (canceled) 
     
     
         20 . A method of increasing antibody serum half-life in a patient comprising administering to said patient an antibody comprising a variant Fc domain as compared to a parent Fc domain, wherein said variant Fc domain comprises the amino acid substitutions M428L/N434A, wherein said antibody has increased in vivo half-life as compared to an antibody comprising said parent Fc polypeptide, and wherein numbering is according to the EU index of Kabat et al. 
     
     
         21 . A protein comprising an Fc variant as compared to a parent IgG1 Fc region, said variant Fc region comprising the amino acid substitutions M428L/N434A, wherein numbering is according to the EU index in Kabat et al. 
     
     
         22 . A protein according to  claim 21  wherein said protein is an antibody. 
     
     
         23 . A nucleic acid encoding an Fc variant as compared to a parent IgG1 Fc region, said variant Fc region comprising the amino acid substitutions M428L/N434A, wherein numbering is according to the EU index in Kabat et al. 
     
     
         24 . An expression vector comprising the nucleic acid of  claim 23 . 
     
     
         25 . A host cell comprising the expression vector of  claim 23 . 
     
     
         26 . A method of making an antibody comprising culturing the host cell of  claim 24  under conditions wherein said antibody is expressed and recovering said antibody.