Composition for inducing proliferation or accumulation of regulatory T cells
It was found that bacteria belonging to the genus Clostridium induce accumulation of regulatory T cells (Treg cells) in the colon. Moreover, the present inventors found that regulatory T cells (Treg cells) induced by from these bacteria suppressed proliferation of effector T-cells. From these findings, the present inventors found that the use of bacteria belonging to the genus Clostridium or a physiologically active substance derived therefrom made it possible to induce proliferation or accumulation of regulatory T cells (Treg cells), and further to suppress immune functions.
1. A method of treating a human subject having an infectious disease, an autoimmune disease, or an allergic disease, the method comprising administering a pharmaceutical composition comprising a purified bacterial mixture of at least two live bacterial strains belonging to Clostridium clusters IV and/or XIVa to the human subject, wherein the bacterial strains are spore-forming bacteria and are isolated from a human.
2. The method of claim 1 , wherein the human subject has an infectious disease.
3. The method of claim 1 , wherein the human subject has an allergic disease.
4. The method of claim 1 , wherein the at least two live bacterial strains belonging to Clostridium clusters IV and/or XIVa comprise two or more strains belonging to Clostridium cluster IV.
5. The method of claim 1 , wherein the at least two live bacterial strains belonging to Clostridium clusters IV and/or XIVa comprise two or more strains belonging to Clostridium cluster XIVa.
6. The method of claim 1 , wherein the at least two live bacterial strains belonging to Clostridium clusters IV and/or XIVa comprise one or more strains belonging to Clostridium cluster IV and one or more strains belonging to Clostridium cluster XIVa.
7. The method of claim 1 , wherein the bacteria are isolated from a chloroform-treated human fecal sample.
8. The method of claim 1 , wherein the pharmaceutical composition comprises a pharmaceutically acceptable excipient.
9. The method of claim 1 , wherein the pharmaceutical composition is administered orally.
10. The method of claim 1 , wherein the pharmaceutical composition is formulated for delivery to the intestine.
11. The method of claim 10 , wherein the pharmaceutical composition comprises a pH sensitive composition comprising one or more enteric polymers.
12. The method of claim 10 , wherein the pharmaceutical composition is in the form of a capsule.
13. The method of claim 1 , wherein the bacteria are in the form of spores.