Immune monitoring of pediatric heart transplant recipients through serial donor specific antibody testing — An initial experience and review of the literature

Heart transplantation is the best therapy for patient with end stage heart failure from cardiomyopathy or congenital heart disease that is not amenable to further surgical palliation. However, the development of rejection, cardiac allograft vasculopathy, and graft failure limit long term survival. Standard tools to assess for these complications include Echo, ECG, endomyocardial biopsy, and coronary angiography. However, the measurement of anti-HLA antibodies before and after transplantation is emerging in the clinical management of pediatric heart transplant recipients. It has been demonstrated that the presence of anti-HLA antibodies prior to transplantation and the development of de novo donor specific antibodies are both associated with poor outcomes. Detection of donor specific antibodies may be useful to monitor highly sensitized patients post transplant and to diagnose and guide clinical decision making in the treatment of antibody mediated rejection. Immunologic monitoring for the presence of these antibodies can be integral to ongoing surveillance. This paper will review the role of the immune system in heart transplantation, discuss concepts of pretransplant allosensitization and post transplant donor specific antibodies, and, finally will review clinical scenarios in which immunologic monitoring through donor specific antibody testing can be helpful.