Success in cardiac transplantation has been achieved by the development of improved immunosuppressive therapies, which have led to a concomitant decrease in cardiac allograft rejection and infection. Rejection however continues to be the cause of significant morbidity and mortality particularly in the first year after cardiac transplantation. The endomyocardial biopsy remains an essential tool for its diagnosis. Acute cellular rejection has been a well recognized phenomenon although more recently, the diagnosis of antibody-mediated rejection has gained acceptance, a condition associated with greater graft dysfunction, subsequent development of cardiac allograft vasculopathy and mortality. In this article we review the current status of the diagnosis of cardiac allograft rejection as determined by the traditional endomyocardial biopsy, the more recent advances in the non-invasive evaluation of rejection, detection of circulating antibodies and the treatment of rejection.
"Cardiac transplantation is the preferred surgical therapy for patients with end-stage heart diseases. However, allograft rejection is the major challenge for the transplantation
. To date, several strategies have been made towards preservation of the transplanted heart by regulating the immune response of the recipients. "
[Show abstract][Hide abstract] ABSTRACT: Background
The spleen is an active lymphoid organ. The effect of splenectomy on the immune response remains unclear. This study investigated whether splenectomy can induce immune tolerance and has a beneficial role in cardiac allograft.
Wistar rats were used for heart donors. The Sprague–Dawley (SD) rats designated as the recipients of heart transplantation (HT) were randomly assigned into four groups: sham, splenectomy, HT, splenectomy + HT. The survival of transplanted hearts was assessed by daily checking of abdominal palpation. At various time points after transplantation, the transplanted hearts were collected and histologically examined; the level of CD4+CD25+ T regulatory lymphocytes (Tregs) and rate of lymphocyte apoptosis (annexin-v+ PI+ cells) in the blood were analyzed by using flow cytometric method.
1) Splenectomy significantly prolonged the mean survival time of heart allografts (7 ± 1.1 days and 27 ± 1.5 days for HT and splenectomy + HT, respectively; n = 12-14/group, HT vs. splenectomy + HT, p < 0.001); 2) Splenectomy delayed pathological changes (inflammatory cell infiltration, myocardial damage) of the transplanted hearts in splenectomy + HT rats; 3) The level of CD4+CD25+ Tregs in the blood of splenectomized rats was significantly increased within 7 days (2.4 ± 0.5%, 4.9 ± 1.3% and 5.3 ± 1.0% for sham, splenectomy and splenectomy + HT, respectively; n = 15/group, sham vs. splenectomy or splenectomy + HT, p < 0.05) after splenectomy surgery and gradually decreased to baseline level; 4) Splenectomy increased the rate of lymphocyte apoptosis (day 7: 0.3 ± 0.05%, 3.9 ± 0.9% and 4.1 ± 0.9% for sham, splenectomy and splenectomy + HT, respectively; n = 15/group, sham vs. splenectomy or splenectomy + HT, p < 0.05) in a pattern similar to the change of the CD4+CD25+ Tregs in the blood.
Splenectomy inhibits the development of pathology and prolongs the survival time of cardiac allograft. The responsible mechanism is associated with induction of immune tolerance via elevating CD4+CD25+ Tregs and increasing lymphocyte apoptosis.
Journal of Cardiothoracic Surgery 05/2013; 8(1):129. DOI:10.1186/1749-8090-8-129 · 1.03 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Cardiac allograft vasculopathy (CAV) is the leading cause of late morbidity and mortality in heart-transplant patients. Increasing evidences support the important role of chemokines and their receptors in transplant immunology. Chemokine-chemokine receptor interaction and subsequent recruitment of T-lymphocytes to the graft are early events in the development of chronic rejection of transplanted hearts. In this study, we first inhibited CC-motif chemokine receptor 5 (CCR5) expression by using lentiviral-mediated gene transfer of an anti-CCR5 siRNA, which introduced through CD34(+) hematopoietic stem/progenitor cell transplantation. Stably marked lymphocytes expressing siRNA and consistent downregulation of CCR5 expression were detected. Our results showed that survival was significantly prolonged in CCR5 knock-down mice and donor hearts from siRNA-treated mice developed markedly less CAV. Infiltration of CD4(+) and CD8(+) T-lymphocytes into transplanted hearts was also markedly decreased. These findings suggest that CCR5 plays an important role in CAV development and inhibition of this chemokine could improve long-term survival after cardiac transplantation.
[Show abstract][Hide abstract] ABSTRACT: Inflammatory processes underlie a broad spectrum of conditions that injure the heart muscle and cause both structural and functional deficits. In this article, we address current knowledge regarding 4 common forms of myocardial inflammation: myocardial ischemia and reperfusion, sepsis, viral myocarditis, and immune rejection. Each of these pathological states has its own unique features in pathogenesis and disease evolution, but all reflect inflammatory mechanisms that are partially shared. From the point of injury to the mobilization of innate and adaptive immune responses and inflammatory amplification, the cellular and soluble mediators and mechanisms examined in this review will be discussed with a view that both beneficial and adverse consequences arise in these human conditions.
Circulation Research 01/2012; 110(1):126-44. DOI:10.1161/CIRCRESAHA.111.243170 · 11.02 Impact Factor
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.