NEW METHODS AND COMPOUNDS FOR THE SELECTIVE MODULATION OF ANTIGEN-SPECIFIC T-CELL RESPONSIVENESS

摘要

The present invention relates to new FcηRII bridging compositions for impairing the capacity of antigen presenting cells (APCs) to stimulate the activation of antigen-specific T-cells, resulting in modulation of antigen-specific T-cell responsiveness. More particularly, said FcηRII bridging agents are chosen from the group consisting of: aggregated human IgG molecules; aggregated Fc fragments of human IgG molecules; a bivalent monoclonal antibody to the FcηRII; a multivalent monoclonal antibody to the FcηRII; a functionally active fragment of said bivalent or multivalent monoclonal antibody; a recombinant fusion protein of 2 or more human IgG Fc parts; liposome vesicles comprising any of the foregoing, provided that said FcηRII composition prevents the expression of the co-stimulatory molecules B7-1/2 and/or down modulates the ICAM-3 molecule expression by these professional APCs. The present invention also relates to prophylactic and therapeutic methods and compositions to prevent or treat the rejection of solid organs, tissues and cells after transplantation; for inducing T-cell anergy or T-cell tolerance; for treating allergic diseases; or for the treatment of autoimmune diseases. The present invention also relates to FcηRII bridged professional APCs prepared by bridging APCs with an FcηRII bridging agent according to the present invention.