Heart Transplant Research Today is a free monthly online journal that collates and summarizes the latest research about Heart Transplant, including details on risks, prognosis, procedure, surgery, organ donation.

Heart and en-bloc thymus transplantation in miniature swine.

Johnston DR, Muniappan A, Hoerbelt R, Guenther DA, Shoji T, Houser SL, Sachs DH, Madsen JC

Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA.

BACKGROUND: Donor-specific tolerance to organ allografts might be induced by cotransplantation of a sufficient amount of vascularized donor thymus. To facilitate donor thymus-induced cardiac allograft tolerance, we have developed a novel technique for heart and en-bloc thymus transplantation in swine. METHODS: Donor heart and en-bloc thymus grafts were prepared by a technique that preserves the entire arterial supply and venous drainage of the right thymic lobe. En-bloc grafts (n = 4) were transplanted heterotopically into the abdomens of major histocompatibility complex-matched miniature swine. Recipients received 12 days of cyclosporine intravenously. Grafts were monitored by palpation, electrocardiographic monitoring, and periodic open biopsy. Engraftment of the donor thymus was demonstrated by measuring the proportion of recipient-type thymocytes in the donor thymus with flow cytometry. RESULTS: All of the heart and en-bloc thymus grafts had normal cardiac contractility and immediate perfusion of the thymus. All en-bloc grafts were accepted for more than 200 days without significant acute cellular rejection or cardiac allograft vasculopathy. Thymic tissue of en-bloc grafts displayed normal architecture and supported thymopoiesis of recipient-type cells. CONCLUSION: We have validated a new technique of donor thymus transplantation that could have utility in human heart transplantation.

Published 3 August 2005 in J Thorac Cardiovasc Surg, 130(2): 554-9.
Full-text of this article is available online (may require subscription).

© 2005-2008 Heart Transplant Research Today. All Rights Reserved.