Antigen-Presenting Cell Populations And Their Use As Reagents For Enhancing Or Reducing Immune Tolerance

Abstract

The present invention is based on the discovery antigen-presenting cells (APCs) may be generated to have predetermined levels of expression of the intracellular enzyme, indoleamine 2,3-dioxygenase (IDO). Because expression of high levels of IDO is correlated with a reduced ability to stimulate T cell responses and an enhanced ability to induce immunologic tolerance, APCs having high levels of IDO may be used to increase tolerance in the immune system, as for example in transplant therapy or treatment of autoimmune disorders. For example, APCs having high levels of IDO, and expressing or loaded with at least one antigen from a donor tissue may be used to increase tolerance of the recipient to the donor's tissue. Alternatively, APCs having reduced levels of IDO expression and expressing or loaded with at least one antigen from a cancer or infectious pathogen may be used as vaccines to promote T cell responses and increase immunity.

1 . A kit for assessing the relative risk of tumor progression in a subject comprising reagents for detection of the enzyme indoleamine 2,3-dioxygenase (IDO) in a sample of tissue from a tumor or tumor draining lymph node from a subject, wherein the reagents are packaged in at least one individual container. 
     
     
         2 . The kit of  claim 1 , further comprising reagents for detection of cell surface or immunohistochemical markers associated with expression of IDO in antigen-presenting cells (APCs). 
     
     
         3 . The kit of  claim 2 , wherein the cell surface markers comprise at least one of the following combinations: (a) CD11c and CD123; or (b) CD11c and CCR6. 
     
     
         4 . The kit of  claim 1 , wherein the reagents comprise an anti-IDO antibody. 
     
     
         5 . The kit of  claim 4 , wherein the anti-IDO antibody is directly labeled with a chemical, fluorescent, or an enzymatic moiety. 
     
     
         6 . The kit of  claim 4 , further comprising a labeled secondary antibody that recognizes the anti-IDO antibody. 
     
     
         7 . The kit of  claim 1 , wherein the reagents comprise an oligonucleotide probe that specifically hybridizes to IDO mRNA for quantification of IDO expression in the sample. 
     
     
         8 . The kit of  claim 1 , wherein the reagents comprise an oligonucleotide primer that specifically hybridizes to IDO cDNA for quantification of IDO expression by reverse-transcriptase PCR. 
     
     
         9 . The kit of  claim 1 , comprising reagents to measure IDO enzymatic activity. 
     
     
         10 . The kit of  claim 1 , further comprising reagents for quantification of IDO by ELISA. 
     
     
         11 . A kit to determine the number of antigen presenting cells that express elevated levels of indoleamine 2,3-dioxygenase (IDO+ APCs) in a human sample of tumor or tumor draining lymph node comprising reagents for detection of cells that express at least one of: (a) IDO; (b) both cell surface markers CD11c and CD123; or (c) both cell surface markers CD11c and CCR6, wherein said reagents are packaged in at least one individual container. 
     
     
         12 . The kit of  claim 11 , wherein the reagents comprise an antibody or antibodies that recognize the at least one of: (a) IDO; (b) both cell surface markers CD11c and CD123; or (c) both cell surface markers CD11c and CCR6. 
     
     
         13 . The kit of  claim 12 , wherein the antibody or antibodies are directly labeled with a chemical, fluorescent, or an enzymatic moiety. 
     
     
         14 . The kit of  claim 12 , further comprising a labeled secondary antibody that recognizes the antibody or antibodies that recognize the at least one of: (a) IDO; (b) both cell surface markers CD11c and CD123; or (c) both cell surface markers CD11c and CCR6. 
     
     
         15 . The kit of  claim 11 , wherein the reagents comprise at least one oligonucleotide probe that specifically hybridizes to IDO mRNA. 
     
     
         16 . The kit of  claim 11 , wherein the reagents comprise at least one oligonucleotide primer that specifically hybridizes IDO cDNA. 
     
     
         17 . The kit of  claim 11 , comprising reagents to measure IDO enzymatic activity. 
     
     
         18 . The kit of  claim 11 , further comprising reagents for quantification of IDO by ELISA. 
     
     
         19 . A kit for assessing the relative risk of tumor progression in a subject comprising reagents to quantify the number of cells in a tumor or tumor draining lymph node expressing at least one of the following combinations of markers: (a) IDO; (b) CD11c and CD123; or (c) CD11c and CCR6. 
     
     
         20 . The kit of  claim 19 , wherein the markers are quantified by flow cytometry or immunohistochemistry.