Methods for detecting a mycobacterium tuberculosis infection

Abstract

Methods for detecting an infection with Mtb in a subject are disclosed. The methods include detecting the presence of CD8 + T cells that specifically recognize an Mtb polypeptide. The methods include in vitro assays for detecting the presence of CD8 + T cells in a biological sample, and in vivo assays that detect a delayed type hypersensitivity reaction. The methods also include detecting Mtb polypeptides and polynucleotides.

1 . A method for detecting  Mycobacterium tuberculosis  in a subject, comprising
 contacting a biological sample from the subject comprising T cells ex vivo with one or more  Mycobacterium  polypeptides, and an antigen presenting cell presenting the one or more  Mycobacterium  polypeptides wherein the one or more  Mycobacterium  polypeptides   (a) the amino acid sequence set forth as SEQ ID NO: 6; or   (b) at least nine to twenty consecutive amino acids of at least one of the amino acid sequence set forth as SEQ ID NO: 6, wherein the nine to twenty consecutive amino acids specifically bind major histocompatibility complex (MHC) class I; and   determining if the T cells specifically recognize the  Mycobacterium  polypeptide, wherein the presence of T cells that specifically recognize the  Mycobacterium  polypeptide detects  Mycobacterium tuberculosis  in the subject.   
     
     
         2 . (canceled) 
     
     
         3 . The method of  claim 1 , wherein the T cells are CD8 +  T cells. 
     
     
         4 . The method of  claim 3 , in which determining if the CD8 +  T cells specifically recognize the  Mycobacterium  polypeptide is determined by measuring secretion of a cytokine from the CD8 +  T cells. 
     
     
         5 . The method according to  claim 4 , wherein the cytokine is interferon (IFN)-γ. 
     
     
         6 . The method of  claim 5 , wherein measuring secretion of IFN-γ is determined using an antibody that specifically binds IFN-γ. 
     
     
         7 . The method of  claim 1 , wherein the biological sample is blood, isolated peripheral blood mononuclear cells, or isolated mononuclear cells 
     
     
         8 . The method of  claim 1 , wherein the T cells are cultured in vitro with the  Mycobacterium  polypeptide. 
     
     
         9 . The method of  claim 1 , wherein the polypeptide is administered to the subject. 
     
     
         10 . A method of detecting a  Mycobacterium tuberculosis  infection in a subject, comprising
 detecting the presence of a  Mycobacterium  polypeptide or a polynucleotide encoding the polypeptide in a sample from the subject, wherein the  Mycobacterium  polypeptide comprises the amino acid sequence set forth SEQ ID NO: 6.   
     
     
         11 . (canceled) 
     
     
         12 . The method of  claim 10 , comprising determining the presence of the  Mycobacterium  polypeptide. 
     
     
         13 . The method of  claim 12 , wherein determining the presence of the  Mycobacterium  polypeptide comprises the use of an antibody that specifically binds the  Mycobacterium  polypeptide. 
     
     
         14 . The method of  claim 10 , comprising determining the presence of the  Mycobacterium  polynucleotide. 
     
     
         15 . The method of  claim 14 , wherein determining the presence of the  Mycobacterium  polypeptide comprises the use of polymerase chain reaction. 
     
     
         16 . The method of  claim 10 , wherein the biological sample is blood, peripheral blood mononuclear cells, sputum, a lung biopsy, a lymph node biopsy, saliva, cerebral spinal fluid or isolated I cells. 
     
     
         17 . A method of detecting  Mycobacterium tuberculosis  in a subject, comprising;
 administering to the subject an effective amount of a  Mycobacterium  polypeptide into the skin of the subject, wherein the  Mycobacterium  polypeptide comprises an amino acid sequence set forth as   (a) the amino acid sequence set forth as SEQ ID NO: 6; or   (b) at least nine to twenty consecutive amino acids of the amino acid sequence set forth as SEQ ID NO: 6, wherein the nine to twenty consecutive amino acids specifically bind major histocompatibility complex (MHC) class I; and   detecting the presence of CD8 +  T cells that specifically recognize the  Mycobacterium  polypeptide in the subject.   
     
     
         18 . (canceled) 
     
     
         19 . The method of  claim 17 , wherein detecting the presence of CD8 +  T cells comprises detecting the presence of CD8 +  T cells in vivo. 
     
     
         20 . The method of  claim 19 , wherein the detecting the presence of CD8 +  T cells comprises detecting a delayed type hypersensitivity reaction. 
     
     
         21 . The method of  claim 20 , wherein the  Mycobacterium  polypeptide is administered intradermally to the subject, and wherein the delayed type hypersensitivity reaction is measure by measuring redness, swelling or induration of the skin. 
     
     
         22 . The method of  claim 1 , wherein the one or more  Mycobacterium  polypeptides comprises the amino acid sequence set forth as SEQ ID NO: 6. 
     
     
         23 . The method of  claim 17 , wherein the one or more  Mycobacterium  polypeptides comprises the amino acid sequence set forth as SEQ ID NO: 6.