Antibody response phenotyping

Abstract

Disclosed herein are methods, systems, mediums, and kits for use in phenotyping antibody responses via devices such as surface plasmon resonance devices. Such phenotypes can include total target-specific antibody titers, quantitative isotype distribution of the target-specific antibodies, and/or epitope specificity of the target-specific antibodies. Other methods, systems, mediums, and kits are also disclosed.

1 . A method of determining with a biosensor device a distribution of target antigen-specific molecules in a biological sample, the method comprising:
 producing a contacted surface by contacting a biorecognition surface of a biosensor device with a biological sample comprising a plurality of target antigen-specific molecules;   determining a total titer of the target antigen-specific molecules immobilized on the contacted surface by detecting with the biosensor device interaction of the target antigen-specific molecules with the biorecognition surface;   exposing under saturation conditions the contacted surface to probe molecules specific for at least some of the target antigen-specific molecules; and   determining the distribution of the target antigen-specific molecules in the biological sample by detecting interaction of the one or more probe molecules with the contacted surface with the biosensor device.   
     
     
         2 . The method according to  claim 1 , wherein each of the steps are performed in a single biological sample run of the biosensor device. 
     
     
         3 . The method according to  claim 1 , further comprising determining epitope specificity of the target antigen-specific molecules. 
     
     
         4 . The method according to  claim 1 , wherein the sample is a blood plasma or serum sample. 
     
     
         5 . The method according to  claim 4 , wherein the sample is a blood plasma sample treated with caprylic acid (CA). 
     
     
         6 . The method according to  claim 1 , wherein the biosensor device is a surface plasmon resonance (SPR) device, and wherein the method is performed in a single SPR run. 
     
     
         7 . The method according to  claim 1 , wherein the biorecognition surface comprises a surface coupled with a capture agent specific for a target antigen, and wherein the target antigen is contacted by the capture agent. 
     
     
         8 . The method according to  claim 7 , wherein the capture agent is a capture antibody. 
     
     
         9 . The method according to  claim 1 , further comprising coupling a capture agent specific for a target antigen to a surface and contacting the capture agent with the target antigen to produce the biorecognition surface. 
     
     
         10 . The method according to  claim 1 , wherein a target molecule comprises immunoglobulin molecules, immunologically active fragments of immunoglobulin molecules, or Factor VIII (FVIII). 
     
     
         11 . The method according to  claim 10 , wherein the target molecule comprises IgG, IgA, IgM, and IgE, IgD, IgA and IgY. 
     
     
         12 . The method according to  claim 11 , wherein the target molecule comprises IgG1, IgG2, IgG3, IgG4, IgA1 and IgA2. 
     
     
         13 . The method according to  claim 1 , wherein a first portion of the probe molecules are specific for a first type of the target antigen-specific molecules, and a second portion of the probe molecules are specific for a second type of the target antigen-specific molecules, and wherein determining the distribution comprises determining the distribution of the first type of the molecules and the distribution of the second type of the molecules in the biological sample. 
     
     
         14 . The method according to  claim 1 , further comprising comparing the determined total titer of the target antigen-specific molecules with the determined distribution of the target antigen-specific molecules and thereby evaluating the accuracy of the determined distribution. 
     
     
         15 . The method according to  claim 1 , wherein exposing the contacted surface to the probe molecules comprises immobilizing at least some of the probe molecules on the contacted surface, and wherein detecting interaction of the one or more probe molecules with the contacted surface comprises measuring an amount of the probe molecules immobilized on the contacted surface. 
     
     
         16 . The method according to  claim 1 , wherein a target molecule comprises a protein to which at least a portion of the plurality of target antigen-specific molecules bind to produce the contacted surface. 
     
     
         17 . The method according to  claim 1 , wherein the target antigen-specific molecules comprise monoclonal antibodies, multispecific antibodies, human antibodies, humanized antibodies, camelised antibodies, chimeric antibodies, single-chain Fvs (scFv), single chain antibodies, Fab fragments, F(ab′) fragments, disulfide-linked Fvs (sdFv), anti-idiotypic (anti-Id) antibodies, epitope-binding fragments, or any combinations thereof.