Use of an anti-CD200 antibody for prolonging the survival of allografts: a patent evaluation of WO2012106634A1.

Background: Allograft rejection continues to be the biggest hurdle in successful organ transplantation. This application (WO2012106634A1) claims the use of blocking CD200 antibody to achieve long-term survival of allografts. CD200 is the ligand for the inhibitory CD200 receptor (CD200R).

Methods: In mouse allograft transplantation models, a blocking CD200 antibody was used to improve renal and cardiac graft survival. Similarly, in humans a blocking CD200 antibody would be administered to the organ recipient in combination with currently used immunosuppressive drugs or even as a monotherapy.

Results: In the presented animal experiments, anti-CD200 antibody application to the allograft recipient decreases SHIP expression in splenocytes. This is accompanied by a significant increase in renal or cardiac graft survival. Furthermore, anti-CD200 antibody has an immunosuppressive effect manifested by an increased production of T regulatory and myeloid-derived suppressor cells (MDSC) and a decrease in B cells and activated T cells.

Conclusion: In vivo administration of anti-CD200 antibody has a remarkable positive effect on allograft survival. However, since this finding contradicts all previous effects of in vivo CD200 manipulation described in transplantation settings, future development of this invention is highly uncertain.