Inhibition of graft versus host disease

Abstract

The development of graft versus host disease in a mammalian patient undergoing cell transplantation therapy for treatment of a bone marrow mediated disease, is prevented or alleviated by subjecting at least the T-cells of the allogeneic cell transplantation composition, extracorporeally, to oxidative stress, in appropriate dosage amounts, such as bubbling a gaseous mixture of ozone and oxygen through a suspension of the T-cells. The process may also include irradiation of the cells with UV light, simultaneously with the application of the oxidative stress. The oxidative stress induces reduced inflammatory cytokine production and a reduced proliferative response in the T-cells.

I claim:  
     
         1 . A process for preparing an allogeneic cell population for administration to a human patient suffering from a bone marrow disorder potentially treatable by bone marrow transplantation, which comprises subjecting, in vitro, a population of donor cells enriched in T-cells to oxidative stress to induce in said T-cells an altered cytokine production profile and a reduced proliferative response.  
     
     
         2 . The process of    claim 1    wherein the oxidative stress is imparted by subjection to an ozone/oxygen gaseous mixture.  
     
     
         3 . The process of    claim 2    wherein the ozone/oxygen gas mixture is bubbled through an aqueous suspension of said T-cell containing population at a rate of from about 0.01-2 liters per minute.  
     
     
         4 . The process of    claim 3    wherein the ozone/oxygen gas mixture has an ozone content of from about 1.0-100 μg/ml.  
     
     
         5 . The process of    claim 2    wherein the ozone/oxygen gas mixture is bubbled through an aqueous suspension of said T-cell containing population at a rate of from about 0.05-1.0 liters per minute, the gas mixture having an ozone content of from about 3-70 μg/ml.  
     
     
         6 . The process of    claim 3    wherein the T-cell containing population is additionally subjected to UV radiation.  
     
     
         7 . The process of    claim 6    wherein the T-cell containing population is subjected to oxidative stress and UV radiation simultaneously.  
     
     
         8 . The process of    claim 7    wherein the UV radiation is UV-C.  
     
     
         9 . The process    claim 8    wherein the time of simultaneous subjection to oxidative stress and UV radiation is from 0.5-60 minutes.  
     
     
         10 . The process of    claim 9    wherein the time is from 2-5 minutes.  
     
     
         11 . The process of    claim 5    wherein the T-cell containing population is a human white blood cell fraction obtained from human peripheral blood by leukopheresis.  
     
     
         12 . The process of    claim 11    wherein the T-cell containing population is a peripheral blood mononuclear cell fraction from human blood.  
     
     
         13 . The process of    claim 1    wherein the oxidative stress is imparted by addition of a chemical oxidizing agent to a suspension of said T-cell enriched donor cell population.  
     
     
         14 . The process of    claim 13    wherein the T-cell enriched donor cell population is a peripheral blood mononuclear cell fraction from human blood.  
     
     
         15 . A process of treating a mammalian patient for alleviation of a bone marrow disorder potentially treatable by bone marrow transplantation, with alleviation of consequentially developed graft versus host disease, which comprising administering to the patient allogeneic hematopoietic stem cells and allogeneic T-cells, at least a portion of said T-cells having been subjected to oxidative stress in vitro, prior to administration to the patient, so as to induce decreased inflammatory cytokine production and a reduced proliferative response therein.  
     
     
         16 . The process of    claim 15    wherein the T-cells are administered separately from the stem cells.  
     
     
         17 . The process of    claim 16    wherein the T-cells consist essentially of peripheral blood mononuclear cells obtained from peripheral human blood.  
     
     
         18 . The process of    claim 16    or wherein the T-cells have been subjected to oxidative stress by application thereto of a gaseous oxygen/ozone mixture.  
     
     
         19 . The process of    claim 16    wherein the T-cells have been subjected to oxidative stress by application thereto of a chemical oxidizing agent.  
     
     
         20 . The process of    claim 18    wherein the T-cells have been additionally subjected to UV radiation, simultaneously with the subjection to oxidative stress.  
     
     
         21 . A population of mammalian T-cells essentially free of stem cells, said T-cells having been subjected in vitro to oxidative stress so as to induce in said cells a reduced inflammatory cytokine production and a reduced proliferative response.  
     
     
         22 . Peripheral blood mononuclear cells obtained from human peripheripheral blood by leukopheresis, said cells having been subjected in vitro to oxidative stress so as to induce in the T-cell component thereof a reduced inflammatory cytokine production and a reduced proliferative response.