Composition for culturing regulatory t cells and use thereof

Abstract

The present invention relates to a method for effectively proliferating regulatory T cells, by which, particularly, in the presence of a fusion protein dimer comprising IL-2. protein or a variant thereof and CD80 protein or a fragment thereof, CD4+, CD25+, and CD127− T cells can be effectively proliferated. In particular, when combined with a predetermined cell culture medium, regulatory T cells such as CD4+, CD25+, and CD127− can be effectively and specifically proliferated. In addition, when the method is used, it has been confirmed that the survival rate of regulatory T cells is remarkably increased as compared to a conventionally used culture method using IL-2, and a significant increase in the yield of Foxp3+ regulatory T cells has been confirmed. Thus, such a proliferation method can be used in the field of cell therapeutic agents using regulatory T cells.

What is claimed is: 
     
         1 . A composition for proliferating regulatory T cells comprising, as an active ingredient, a fusion protein dimer containing an IL-2 protein or a variant thereof and a CD80 protein or a fragment thereof. 
     
     
         2 . The composition for proliferating regulatory T cells according to  claim 1 , wherein the IL-2 protein or a variant thereof and the CD80 protein or a fragment thereof are attached via a linker. 
     
     
         3 . The composition for proliferating regulatory T cells according to  claim 1 , wherein the IL-2 protein has the amino acid sequence of SEQ ID NO: 10. 
     
     
         4 . The composition for proliferating regulatory T cells according to  claim 1 , wherein the CD80 has the amino acid sequence of SEQ ID NO: 11. 
     
     
         5 . The composition for proliferating regulatory T cells according to  claim 1 , wherein the fusion protein has the amino acid sequence of SEQ ID NO: 9. 
     
     
         6 . The composition for proliferating regulatory T cells according to  claim 1 , wherein the regulatory T cells are CD4+CD25+CD127− cells. 
     
     
         7 . The composition for proliferating regulatory T cells according to  claim 1 , wherein the fusion protein further comprises Fc domain. 
     
     
         8 . The composition for proliferating regulatory T cells according to  claim 1 ,
 wherein the fusion protein comprises the following structural formula (I) or (II):
   N′-X-[linker(1)]n-Fc domain-[linker(2)]m-Y-C′-  formula (I)
 
   N′-Y-[linker(1)]n-Fc domain-[linker(2)]m-X-C′-  formula (II),
 
   wherein, N′ is the N-terminus of the fusion protein,   C″ is the C-terminus of the fusion protein,   X is a CD80 protein or a fragment thereof,   Y is an IL-2 protein or a variant thereof,   the linkers (1) and (2) are peptide linkers, and   n and m are each independently 0 or 1.   
     
     
         9 . A medium for proliferating regulatory T cells comprising a fusion protein dimer containing an IL-2 protein or a variant thereof and a CD80 protein or a fragment thereof. 
     
     
         10 . The medium for proliferating regulatory T cells according to  claim 9 , further comprising a CD4+ T cell culture medium. 
     
     
         11 . The medium for proliferating regulatory T cells according to  claim 10 , wherein the CD4+ T cell culture medium includes amino acids, sugars, inorganic salts, and vitamins. 
     
     
         12 . A method for culturing a regulatory T cells comprising:
 culturing a regulatory T cells in a medium comprising a fusion protein dimer containing an IL-2 protein or a variant thereof and a CD80 protein or a fragment thereof.   
     
     
         13 . The method according to  claim 12 , wherein the IL-2 protein or a variant thereof and the CD80 protein or a fragment thereof are attached via a linker. 
     
     
         14 . The method according to  claim 12 , wherein the IL-2 protein has the amino acid sequence of SEQ ID NO: 10. 
     
     
         15 . The method according to  claim 12 , wherein the CD80 has the amino acid sequence of SEQ ID NO: 11. 
     
     
         16 . The method according to  claim 12 , wherein the fusion protein has the amino acid sequence of SEQ ID NO: 9. 
     
     
         17 . The method according to  claim 12 , wherein the fusion protein further comprises Fc domain. 
     
     
         18 . The method according to  claim 12 , wherein the fusion protein comprises the following structural formula (I) or (II):
   N′-X-[linker(1)]n-Fc domain-[linker(2)]m-Y-C′-  formula (I)
     N′-Y-[linker(1)]n-Fc domain-[linker(2)]m-X-C′-  formula (II),
   wherein, N′ is the N-terminus of the fusion protein,   C″ is the C-terminus of the fusion protein,   X is a CD80 protein or a fragment thereof,   Y is an IL-2 protein or a variant thereof,   the linkers (1) and (2) are peptide linkers, and   n and m are each independently 0 or 1.   
     
     
         19 . The method according to  claim 12 , wherein the regulatory T cells are a CD4+CD25+CD127− cells. 
     
     
         20 . The method for culturing regulatory T cells according to  claim 19 , wherein the CD4+CD25+CD127− T cells are obtained by culturing CD4+ T cells; or culturing CD25+ T cells.