Immunological Aspect on Late Allograft Dysfunction

Organ transplantation is a well-accepted treatment for patients with end-stage organ failure. Despite continued improvement in short-term graft survival, late allograft dys-function remains a significant problem in the clinic, especially in kidney transplant patients. Many factors contribute to late graft dysfunction, and among them immunological factors are the leading cause of late grafts loss. In this special issue, we have solicited a set of interesting papers addressing some aspects of this important topic in the field. Here we focused on antibody-mediated rejection (AMR), as AMR is emerging as a major barrier to long-term graft survival, and the donor-specific antibodies are directly involved in AMR. The paper by Q. Sun and Y. Yang provides a comprehensive overview of the characteristics of AMR, both in acute rejection and late chronic rejection, and the current strategies in managing AMR. S. Lionaki et al. provide us with an excellent review on the incidence and clinical significance of de novo donor specific antibodies (DSA) after renal transplantation. It is well recognized that transplant glomerulopathy is a very special entity of late AMR, and Dr. W. Hanf from Australia discussed the effect of donor HLA antibodies on endothelium in transplant settings. These three review papers provide an extensive overview on antibody reactivity and its correlation with late graft injury. On the mechanistic side, while C4d remains a marker of a humoral response, recent evidence indicates that, in renal allografts, microvascular injury in the presence of donor antibodies is indicative of antibody mediated graft injury. X. Li et al. confirmed that AMR is characterized with early capillary dilation, which is strongly correlated with intracap-illary inflammation. They also discussed the diagnostic value of transcription factors T-bet/GATA3 ratio in predicting AMR, which may be of value in diagnosis of C4d-negative AMR. The treatment of chronic ongoing AMR remains controversial. A group headed by C. W. Yang investigated the effect of combination therapy with rituximab and intravenous immunoglobulin on the progression of chronic AMR. They found that this therapy can delay the progression of chronic AMR. However, higher baseline proteinuria levels are associated with poor response to the treatment. In another paper, H. Petra et al. evaluated differences in the intrarenal expression patterns of immune related genes in acute and chronic rejections. They found that Banff 2007 chronic rejection categories did not differ in intrarenal expression of 376 selected genes associated with immune response. There are evidences that characters in …