Stimulation of therapeutic angiogenesis by t regulatory cells

Abstract

Disclosed herein are new, useful, and non-obvious means of stimulating therapeutic angiogenesis, or conditions favorable for stimulation of therapeutic angiogenesis utilizing T regulatory cells. One disclosed method includes administering a population of T regulatory cells into an area of hypoxia to stimulate angiogenesis. T regulatory cells are generated and expanded by culture with mesenchymal stem cells, with either population or both populations together administered into the hypoxic area.

1 . A method of stimulating angiogenesis, comprising:
 obtaining a population of cells comprising T regulatory cells;   selecting said T regulatory cells from said population of cells;   activating said T regulatory cells to enhance angiogenic activity of said T regulatory cells; and   administering said T regulatory cells to a patient in need of therapy.   
     
     
         2 . The method of  claim 1 , wherein said population of cells containing T regulatory cells comprises one or more of peripheral blood mononuclear cells, cord blood, menstrual blood, or adipose derived stromal vascular fraction cells. 
     
     
         3 . The method of  claim 1 , wherein said activated T regulatory cells are administered in an amount of about 2×10 6  cells. 
     
     
         4 . The method of  claim 1 , wherein stimulating angiogenesis treats critical limb ischemia in a subject. 
     
     
         5 . The method of  claim 1 , wherein the activated T regulatory cells are administered by intramuscular injection in an amount of about 1-90 million cells per injection. 
     
     
         6 . The method of  claim 1 , wherein said T regulatory cells inhibit proliferation of naïve T cells stimulated with a signal that activates proliferation. 
     
     
         7 . The method of  claim 1 , wherein said T regulatory cells express glucocorticoid-induced TNFR-related (GITR) ligand, express neuropilin-1, CTLA-4, membrane bound TGF-β, Foxp3, CD25, CD39, CD73, CD105, CD127, or glycoprotein A repetitions predominant (GARP). 
     
     
         8 . The method of  claim 1 , wherein activating said T regulatory cells further comprises exposing said T regulatory cells to vasoactive intestinal peptide, IL-10, TGF-β, mesenchymal stem cell conditioned media, mesenchymal stem cell derived exosomes, brain-derived neurotrophic factor (BDNF), human chorionic gonadotropin, vascular endothelial growth factor (VEGF), hypoxic conditions, angiopoietin, or rapamycin. 
     
     
         9 . A method of stimulating angiogenesis comprising administering a T regulatory cell into an ischemic tissue. 
     
     
         10 . The method of  claim 9 , wherein said ischemic tissue is a limb of a patient suffering from one or more of peripheral artery disease, critical limb ischemia, coronary artery disease, or heart disease. 
     
     
         11 . The method of  claim 9 , wherein said T regulatory cell expresses the marker CD25 or CTLA4. 
     
     
         12 . The method of  claim 9 , wherein said T regulatory cell inhibits proliferation of an activated T cell by more than 25% at a ratio of 1 T regulatory cell to 1 activated T cell. 
     
     
         13 . The method of  claim 9 , wherein said T regulatory cell is derived from cord blood, peripheral blood, menstrual blood, or mobilized peripheral blood. 
     
     
         14 . The method of  claim 9 , wherein said activation of said T regulatory cell is achieved by one or more of IL-2, rapamycin, anti-CD3 antibody, or anti-CD28 antibody. 
     
     
         15 . The method of  claim 9 , wherein said T regulatory cell is cultured with mesenchymal stem cells. 
     
     
         16 . A method of expanding T regulatory cells, comprising:
 culturing a population of cells comprising T regulatory cells; and   enriching CD25+ cells.   
     
     
         17 . The method of  claim 16 , wherein said population of cells containing T regulatory cells comprises one or more of peripheral blood mononuclear cells, cord blood, menstrual blood, or adipose derived stromal vascular fraction cells. 
     
     
         18 . The method of  claim 16 , further comprising culturing said population of cells with a mesenchymal stem cell feeder layer. 
     
     
         19 . A method for in vivo treatment of an immune competent model of critical limb ischemia, comprising:
 administering in vitro expanded T regulatory cells to the immune competent model, wherein the expanded T regulatory cells stimulate angiogenesis in said model.   
     
     
         20 . The method of  claim 19 , wherein administering results in limb salvage.