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.

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.

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.

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.

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.

The present invention relates to a pharmaceutical composition for treating and/or preventing arthritis, which comprising, as an active ingredient, a gene delivery vehicle into which an IK factor or a fragment thereof, or a nucleic acid encoding thereof is inserted. IK factor or the fragment thereof, and the nucleic acid encoding thereof, which are the active ingredient of the pharmaceutical composition according to the present invention, are derived from an organism and therefore, show no side effects in administered into a subject for a long time. Accordingly, they ensures safety and are expected to effectively treat arthritis by being involved in the upstream mechanism for suppressing arthritis.

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.

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.

The present invention relates to a pharmaceutical composition for treating and/or preventing arthritis, which comprising, as an active ingredient, a gene delivery vehicle into which an IK factor or a fragment thereof, or a nucleic acid encoding thereof is inserted. IK factor or the fragment thereof, and the nucleic acid encoding thereof, which are the active ingredient of the pharmaceutical composition according to the present invention, are derived from an organism and therefore, show no side effects in administered into a subject for a long time. Accordingly, they ensures safety and are expected to effectively treat arthritis by being involved in the upstream mechanism for suppressing arthritis.

The invention relates to the development of an animal model for testing various agents in the treatment of a clotting disorder. More specifically, the invention relates to the use of ultra-large molecular weight multimers of von Willebrand factor (VWF) in various mouse strains to induce thrombotic thrombocytopenic purpura (TTP)-like symptoms for the development of a mouse model of TTP. The invention also provides methods for generating such animal disease models and screening methods for identifying biologically active compounds which are effective in the treatment of TTP.