All Rights Reserved. No part of the contents of this document may be reproduced or transmitted in any form or by any means without the written permission of the publisher. 4 Standard Guidance A. General Provisions A.1 Basis and Scope A.1.1 This document sets forth the conditions that a laboratory must satisfy in order to be accredited by the American Society for Histocompatibility and Immunogenetics (ASHI) to perform testing on human specimens. These Standards have been established by the ASHI Quality Assurance and Standards Committee following review, and response to, public comments. These Standards have been approved by the ASHI Board of Directors. These Standards have been established to help ensure accurate and dependable immunogenetics, histocompatibility, and transplantation testing consistent with the current state of wellestablished laboratory procedures. A.1.2 All laboratories requesting ASHI accreditation must meet the same requirements, regardless of their location in the U.S. or a foreign country and regardless of whether or not they are using ASHI accreditation for compliance with CLIA regulations. Re: A.1.2-Certain rare cases in which Standards are indicated to apply only to UNOS laboratories or only to U.S. Laboratories (e.g., the requirement to include the FDA disclaimer on reports) are exceptions to Standard A.1.2 A.2 Abbreviations ARB Accreditation Review Board ASHI The American Society for Histocompatibility and Immunogenetics. CDC Centers for Disease Control and Prevention CFR US Code of Federal Regulations CLIA Clinical Laboratory Improvement Amendments of 1988. CLIA regulations are defined in 42 CFR 493. CMS US Centers for Medicare and Medicaid Services CPRA Calculated Panel Reactive Antibody CREG Cross Reactive Group DNA Deoxyribonucleic acid EFI European Federation for Immunogenetics ELISA Enzyme-linked immunosorbent assay

The renin-angiotensin system (RAS) plays an important role in the regulation of inflammation and in the progression of chronic kidney disease. Accumulation of inflammatory cells into the renal parenchyma has been a hallmark of chronic kidney disease; however, little is known concerning the presence and the function of RAS elements in T and natural killer (NK) cells. Here is reported a co-stimulatory effect of angiotensin II (AngII) by showing an augmentation of mitogen and anti-CD3-stimulated T and NK cell proliferation with AngII treatment. Angiotensinogen and AngI also generated the same effect, suggesting that NK and T cells have functional renin and angiotensin-converting enzyme activity. Indeed, they express renin, the renin receptor, angiotensinogen, and angiotensin-converting enzyme by mRNA analysis. Flow cytometric analysis and Western blot revealed angiotensin receptor 2 (AT 2 ) expression in T and NK cells, whereas AT 1 expression was found in T and NK cells and monocytes by Western blot. These receptors were shown to be functional in calcium signaling, chemotaxis, and proliferation. However, AT 1 and AT 2 antagonists alone or in combination were unable to abrogate completely the effects of AngII, suggesting that another AngII receptor may also be functional in leukocytes. This is the first study to show that T and NK cells are fully equipped with RAS elements and are potentially capable of producing and delivering AngII to sites of inflammation. Because their chemotaxis is enhanced by AngII, this creates a potential inflammatory amplification system. B ecause of its hemodynamic effects, angiotensin II (AngII) plays a central role in the progression of chronic kidney diseases (CKD) and ischemic heart disease (1,2). AngII has been shown to be a potent proinflammatory molecule, and the beneficial effects of renin-angiotensin system (RAS) blockade are due not only to lowering BP but also to a reduction in inflammation (3). One of the main features of CKD is the accumulation of inflammatory cells, which plays a crucial role in disease progression (4), and recruitment of macrophages to the kidney through AngII infusion has been reported in various rodent models (5,6). In both diabetic nephropathy and atherosclerosis, monocytes/macrophages have been reported to play a key role (7-9). Monocytes have also been the primary focus of studies that have examined the interaction of AngII and inflammatory cells (10). However, the importance of T, natural killer (NK), and dendritic cells (DC) in inflammation and vascular disease has only recently begun to be appreciated. DC have been shown to present oxidized LDL to T cells, generating autoreactive T cells and promoting arterial injury (11). NK cells participate through the production of proatherogenic cytokines such as IFN-␥ (12). Previous studies on AngII-induced inflammation and its role in kidney disease primarily focused on the induction of inflammatory molecules and the paracrine effects of AngII in vascular remodeling and tissue fibrosis (13,14). Despite these ...

The presence of preexisting (memory) or de novo donor-specific HLA antibodies (DSAs) is a known barrier to successful long-term organ transplantation. Yet, despite the fact that laboratory tools and our understanding of histocompatibility have advanced significantly in recent years, the criteria to define presence of a DSA and assign a level of risk for a given DSA vary markedly between centers. A collaborative effort between the American Society for Histocompatibility and Immunogenetics and the American Society of Transplantation provided the logistical support for generating a dedicated multidisciplinary working group, which included experts in histocompatibility as well as kidney, liver, heart, and lung transplantation. The goals were to perform a critical review of biologically driven, state-of-the-art, clinical diagnostics literature and to provide clinical practice recommendations based on expert assessment of quality and strength of evidence. The results of the Sensitization in Transplantation: Assessment of Risk (STAR) meeting are summarized here, providing recommendations on the definition and utilization of HLA diagnostic testing, and a framework for clinical assessment of risk for a memory or a primary alloimmune response. The definitions, recommendations, risk framework, and highlighted gaps in knowledge are intended to spur research that will inform the next STAR Working Group meeting in 2019.

The impact of donor‐specific HLA alloantibodies (DSA) on short‐ and long‐term liver transplant outcome is not clearly defined. While it is clear that not all levels of allosensitization produce overt clinical injury, and that liver allografts possess some degree of alloantibody resistance, alloantibody‐mediated adverse consequences are increasingly being recognized. To better define the current state of this topic, we assembled experts to provide insights, explore controversies and develop recommendations for future research on the consequences of DSA in liver transplantation. This article summarizes the proceedings of this inaugural meeting. Several insights emerged. Acute antibody‐mediated rejection (AMR), although rarely diagnosed, is increasingly understood to overlap with T cell–mediated rejection. Isolated liver allograft recipients are at increased risk of early allograft immunologic injury when preformed DSA are high titer and persist posttransplantation. Persons who undergo simultaneous liver–kidney transplantation are at risk of renal AMR when Class II DSA persist posttransplantation. Other under‐appreciated DSA associations include ductopenia and fibrosis, plasma cell hepatitis, biliary strictures and accelerated fibrosis associated with recurrent liver disease. Standardized DSA testing and diagnostic criteria for both acute and chronic AMR are needed to distil existing associations into etiological processes in order to develop responsive therapeutic strategies.

Concerns about adverse effects of calcineurin inhibitors (CNIs) have prompted development of protocols that minimize their use. Whereas previous CNI withdrawal trials in heterogeneous cohorts showed unacceptable rates of acute rejection (AR), we hypothesized that we could identify individuals capable of tolerating CNI withdrawal by targeting immunologically quiescent kidney transplant recipients. The Clinical Trials in Organ Transplantation-09 Trial was a randomized, prospective study of nonsensitized primary recipients of living donor kidney transplants. Subjects received rabbit antithymocyte globulin, tacrolimus, mycophenolate mofetil, and prednisone. Six months post-transplantation, subjects without de novo donor-specific antibodies (DSAs), AR, or inflammation at protocol biopsy were randomized to wean off or remain on tacrolimus. The intended primary end point was the change in interstitial fibrosis/tubular atrophy score between implantation and 24-month protocol biopsies. Serially collected urine CXCL9 ELISA results were correlated with outcomes. The study was terminated prematurely because of unacceptable rates of AR (4 of 14) and/or de novo DSAs (5 of 14) in the tacrolimus withdrawal arm. Positive urinary CXCL9 predated clinical detection of AR by a median of 15 days. Analyses showed that .16 HLA-DQ epitope mismatches and pretransplant, peripheral blood, donor-reactive IFN-g ELISPOT assay results correlated with development of DSAs and/or AR on tacrolimus withdrawal. Although data indicate that urinary CXCL9 monitoring, epitope mismatches, and ELISPOT assays are potentially informative, complete CNI withdrawal must be strongly discouraged in kidney transplant recipients who are receiving standard-of-care immunosuppression, including those who are deemed to be immunologically quiescent on the basis of current clinical and laboratory criteria.

Delayed graft function (DGF) associates with an increased risk for graft failure, but its link with death with graft function (DWGF) is unknown. We used the US Renal Data System to assemble a cohort of all first, adult, deceased-donor kidney transplant recipients from January 1, 1998, through December 31, 2004. In total, 11,542 (23%) of 50,246 recipients required at least one dialysis session in the first week after transplantation. Compared with patients without DGF, patients with DGF were significantly more likely to die with a functioning graft (relative hazard 1.83 [95% confidence interval 1.73 to 1.93] and 1.53 [95% CI 1.45 to 1.63] for unadjusted and fully adjusted models, respectively). The risk for DWGF was slightly higher among women with DGF than among men. There was no significant heterogeneity among other subgroups, and the results were robust to sensitivity analyses. Acute rejection within the first year attenuated the DGF-DWGF association. Cardiovascular and infectious deaths were slightly more prevalent in the DGF group, but the relative hazards of cause-specific death were similar between DWGF and deaths during total follow-up. In summary, DGF associates with an increased risk for DWGF; the mechanisms underlying the negative impact of DGF require further study.

HLA antigens are polymorphic proteins expressed on donor kidney allograft endothelium and are critical targets for recipient immune recognition. HLA antibodies are risk factors for acute and chronic rejection and allograft loss. Solid-phase immunoassays for HLA antibody detection represent a major advance in sensitivity and specificity over cell-based methods and are widely used in organ allocation and pretransplant risk assessment. Post-transplant, development of de novo donorspecific HLA antibodies and/or increase in donor-specific antibodies from pretransplant levels are associated with adverse outcomes. Although single antigen bead assays have allowed sensitive detection of recipient HLA antibodies and their specificities, a number of interpretive considerations must be appreciated to understand test results in clinical and research contexts. This review, which is especially relevant for clinicians caring for transplant patients, discusses the technical aspects of single antigen bead assays, emphasizes their quantitative limitations, and explores the utility of HLA antibody testing in identifying and managing important pre-and post-transplant clinical outcomes.

The results suggest that the biopsy findings and clinical course in patients with focal PTC C4d staining are similar to those associated with diffuse C4d.