Peptides for detection of antibody to Ehrlichia equi

Abstract

The invention provides compositions and methods for the detection and quantification of Ehrlichia equi antibodies and antibody fragments.

I claim:  
     
         1 . A composition of matter consisting essentially of an isolated polypeptide shown in SEQ ID NO:1 or SEQ ID NO:2.  
     
     
         2 . The composition of  claim 1 , further comprising a carrier.  
     
     
         3 . The composition of  claim 1 , wherein the isolated polypeptide is conjugated to bovine serum albumin.  
     
     
         4 . An isolated polynucleotide encoding the isolated polypeptide of  claim 1 .  
     
     
         5 . A composition of matter consisting essentially of an isolated polypeptide fragment of at least about 5 contiguous amino acids of SEQ ID NO:1 or SEQ ID NO:2.  
     
     
         6 . An isolated polynucleotide encoding the isolated polypeptide of  claim 5 .  
     
     
         7 . A method of detecting antibodies specific for  Ehrlichia equi  comprising: 
 (a) contacting a polypeptide shown in SEQ ID NO:1, SEQ ID NO:2 or both SEQ ID NO:1 and SEQ ID NO:2 with a test sample suspected of comprising antibodies specific for  Ehrlichia equi , under conditions that allow polypeptide/antibody complexes to form;    (b) detecting polypeptide/antibody complexes;    wherein the detection of polypeptide/antibody complexes is an indication that antibodies specific for  Ehrlichia equi  are present in the test sample.    
     
     
         8 . The method of  claim 7 , further comprising contacting the complexes of step (a) with an indicator reagent comprising a signal generating compound prior to the performance of step (b).  
     
     
         9 . The method of  claim 7 , wherein the antibodies are fragments of antibodies.  
     
     
         10 . The method of  claim 7 , wherein the amount of antibody in a test sample is determined.  
     
     
         11 . The method of  claim 7 , wherein the polypeptide is attached to a substrate.  
     
     
         12 . The method of  claim 7 , wherein the polypeptide provided is shown in SEQ ID NO:1.  
     
     
         13 . The method of  claim 7 , wherein the polypeptide provided is shown in SEQ ID NO:2.  
     
     
         14 . The method of  claim 7 , wherein the polypeptide is provided in a multimeric form.  
     
     
         15 . The method of  claim 7 , wherein the test sample is a biological sample obtained from a mammal.  
     
     
         16 . The method of  claim 15 , wherein the mammal is selected from the group consisting of humans, cats, horses and dogs.  
     
     
         17 . The method of  claim 7 , wherein the method comprises an assay selected from the group of assays consisting of a reversible flow chromatographic binding assay, an enzyme linked immunosorbent assay, a radioimmunoassay, a hemagglutination assay a western blot assay, a fluorescence polarization immunoassay and an indirect immunofluorescence assay.  
     
     
         18 . An article of manufacture comprising packaging material and, contained within the packaging material, a polypeptide shown in SEQ ID NO:1, SEQ ID NO:2, or both polypeptides shown in SEQ ID NO:1 and SEQ H) NO:2.  
     
     
         19 . The article of manufacture of  claim 18 , wherein the packaging material comprises a label that indicates that the one or more polypeptides can be used for the identification of  Ehrlichia equi  infection in a mammal.  
     
     
         20 . The article of manufacture of  claim 18 , wherein the identification of an  Ehrlichia equi  infection is done using a method of detecting antibodies specific for  Ehrlichia equi  comprising: 
 (a) contacting a polypeptide shown in SEQ ID NO:1, SEQ ID NO:2, or both SEQ ID NO:1 and SEQ ID NO:2, with a test sample suspected of comprising antibodies specific for  Ehrlichia equi , under conditions that allow polypeptide/antibody complexes to form;    (b) detecting polypeptide/antibody complexes;    wherein the detection of polypeptide/antibody complexes is an indication that an  Ehrlichia equi  infection is present.    
     
     
         21 . A method of diagnosing an  Ehrlichia equi  infection in a mammal comprising: 
 (a) obtaining a biological sample from a mammal suspected of having an  Ehrlichia equi  infection;    (b) contacting a polypeptide shown in SEQ ID NO:1, SEQ ID NO:2, or both SEQ ID NO:1 and SEQ ID NO:2, with the biological sample under conditions that allow polypeptide/antibody complexes to form;    (c) detecting polypeptide/antibody complexes;    wherein the detection of polypeptide/antibody complexes is an indication that the mammal has an  Ehrlichia equi  infection.    
     
     
         22 . The method of  claim 21 , further comprising contacting the complexes of step (b) with an indicator reagent comprising a signal generating compound that generates a measurable signal prior to the performance of step (c).  
     
     
         23 . The method of  claim 21 , wherein the mammal is selected from the group consisting of humans, cats, horses and dogs.  
     
     
         24 . An antibody that specifically binds to at least one epitope of an  Ehrlichia equi  polypeptide, wherein said polypeptide is SEQ ID NO:1 or SEQ ID NO:2.  
     
     
         25 . The antibody of  claim 24 , wherein the antibody is a monoclonal antibody.