Transplantation is one of the most challenging and complex areas of modern medicine. Some of the key areas for medical management are the problems of transplant rejection, during which the body has an immune response to the transplanted organ, possibly leading to transplant failure and the need to immediately remove the organ from the recipient.
Dragun et al. have reported the presence of antibodies against AT1R in 16 renal allograft recipients who had severe vascular rejection and malignant hypertension but no donor HLA specific antibodies (HLA-DSA) New England Journal of Medicine (2005), 352, 558-569
Prof. N. Reinsmoen, Cedars-Sinai Medical Center, Los Angeles, and Prof. D. Dragun, Charite Medical School, Berlin, investigated the impact of the antibody to AT1R on clinical outcomes including antibody mediated rejection (AMR), with or without C4d deposition, in patients whose sera contained no donor human leukocyte antigen (HLA)-specific antibody (HLA-DSA).
A strong association was observed between the high binding affinity of AT1R antibodies to AT1R and AMR in recipients whose sera contained no antibody to donor HLA or MICA. Assessing the AT1R antibody status along with the HLA-DSA provides additional information to determine the immunologic risk for recipients. Transplantation (2010), 90, 1473-1477
Prof. R. Kerman, University of Texas Medical School, Houston, and Prof. D. Dragun, Charite Medical School, Berlin, investigated the impact of angiotensin-receptor-I auto antibodies (AT1R-Ab) and / or DSA on the graft survival in kidney allograft recips. The data suggests that AT1R Abs results in decreased long term survival, but if patients have both AT1R and DSA Abs they act synergistically to result in the poorest graft survival. Determining the presence of both a non-HLA (AT1R Ab) and donor specific HLA Ab (DSA) may be more informative of the patient’s immune risk and may guide immunosuppressive therapy.
PD Dr. M. Barten and Prof. F. Mohr, Heart Center Leipzig, and Prof. D. Dragun, Charite Medical School, Berlin, showed that early and higher incidence of cardiac allograft vasculopathy (CAV) after heart transplantation is linked to angiotensin-receptor-I auto antibodies and endothelin-receptor-A auto antibodies. These results point out the necessity of monitoring HLA and non-HLA antibodies after HTx.
Both works were presented at the American Transplant Congress 2011 in Philadelphia:
- Association of AT1R-AB to Renal Allograft Survival
- Early and higher Incidence of Cardiac Allograft Vasculopathy after Heart Transplantation is linked to Non-HLA Antibodies
The CE-labeled, cell based AT1R-antibody-ELISA and ETAR-Antibody-ELISA are the first ELISAs for routine screening in sera or plasma.