6OR A case of rejection in 10/10 allele matched transplant with “high titer low avidity” HLA-DP donor specific antibodies (original) (raw)

Pretransplant Donor-Specific HLA Antibodies Detected by Single Antigen Bead Flow Cytometry: Risk Factors and Outcomes After Kidney Transplantation

Transplantation Proceedings, 2012

Background. The clinical significance of pretransplant donor-specific antibodies (pre-Tx DSAs) detected by single antigen bead flow cytometry (SAB-FC) remains unclear. Our aim was to investigate the impact that pre-Tx DSAs detected by SAB-FC have on the early and late clinical outcomes. Patients and methods. We retrospectively tested stored frozen pre-Tx sera from 222 deceased-donor kidney transplants performed between November 1997 and November 2006. All patients had a negative complement-dependent cytotoxicity (CDC) cross-match with the donor. Median follow up was 5.1 years. Results. Twenty-two (10%) patients had pre-Tx HLA antibodies detected by CDC. Pre-Tx HLA antibodies were detected using SAB-FC in the sera of 46 (20.7%) patients; 36 (16.2%) of them presented pre-Tx DSAs, 18 had class I antibodies, 9 class II, and 9 patients presented both classes. Mean pre-Tx DSA class I/II was 2360/1972 (MFI) mean fluorescence index in non CDC-sensitized patients. Pre-Tx DSAs were associated with female sex, retransplants, and pretransplant transfusions. Patients with Pre-Tx DSAs more than 1000 MFI and negative CDC screening presented a higher percentage of delayed graft function (61.1% versus 38.9%), more episodes of acute vascular rejection (33.3% versus 13.7%), and chronic rejection as the cause of allograft failure (22.2% versus 9.7%) compared with non-pre-Tx DSAs patients. Five-year allograft survival was significantly worse in patients with pre-Tx DSA (68.5% versus 82%, P ϭ .006) and in patients with pre-Tx DSA class II more than 1000 MFI (43% versus 82%, P ϭ .009). We didn't find differences in patient survival. Discussion. Pre-Tx DSAs detected by SAB-FC were more frequent in female recipients, and they were associated with acute vascular and chronic rejection and a poorer graft outcome.

The role of HLA antibodies in allogeneic SCT: is the ‘type-and-screen’ strategy necessary not only for blood type but also for HLA?

Bone Marrow Transplantation, 2012

The role of HLA antibodies in SCT has drawn increasing attention because of the significantly increased number of patients who receive HLA-mismatched SCT, including cord blood transplantation, haploidentical SCT and unrelated SCT. Technical advancements in the methods of HLA Ab testing have realized rapid, accurate and objective identification, as well as quantification of specific HLA antibodies. Recent clinical studies have suggested that the presence of donor-specific HLA antibodies (DSA) in patients is associated with graft failure in HLA-mismatched SCT when the above-listed stem cell sources are used and results in different impacts. Of note, most of the 'HLA-matched' unrelated SCT actually involve HLA mismatches in HLA-DP and the presence of antibodies against this locus has been reported to be associated with graft failure. Thus, HLA Ab should be examined as a work-up for all patients who undergo SCT from 'alternative donors.' The simplest route for preventing HLA Ab-mediated graft failure in Ab-positive patients is to avoid donors who possess the target Ag of HLA antibodies. If SCT from such donors must be performed, treatment for DSA before SCT may improve the chances of successful donor engraftment.

On the clinical relevance of using complete high-resolution HLA typing for an accurate interpretation of posttransplant immune-mediated graft outcomes

Frontiers in Immunology

Complete and high-resolution (HR) HLA typing improves the accurate assessment of donor–recipient compatibility and pre-transplant donor-specific antibodies (DSA). However, the value of this information to identify de novo immune-mediated graft events and its impact on outcomes has not been assessed. In 241 donor/recipient kidney transplant pairs, DNA samples were re-evaluated for six-locus (A/B/C/DRB1/DQB1+A1/DPB1) HR HLA typing. De novo anti-HLA antibodies were assessed using solid-phase assays, and dnDSA were classified either (1) as per current clinical practice according to three-locus (A/B/DRB1) low-resolution (LR) typing, estimating donor HLA-C/DQ typing with frequency tables, or (2) according to complete six-locus HR typing. The impact on graft outcomes was compared between groups. According to LR HLA typing, 36 (15%) patients developed dnDSA (LR_dnDSA+). Twenty-nine out of 36 (80%) were confirmed to have dnDSA by HR typing (LR_dnDSA+/HR_dnDSA+), whereas 7 (20%) did not (LR_d...

On the role of HLA antibodies in hematopoietic stem cell transplantation

Tissue Antigens, 2012

While the role of donor-specific antibodies (DSA) in solid organ transplantation is well established, their importance in hematopoietic stem cell transplantation (HSCT) is only now becoming clear. A review of the literature reporting on HLA immunization in HSCT provides ample circumstantial evidence that donor-specific HLA antibodies (DSA) are associated with a 2-to 10-fold increase of graft failure of HLA mismatched HSCT, irrespective the type of the graft, or the patient conditioning. Nevertheless, this is not a condition 'sine qua non', and engraftment has been documented despite the presence of DSA. However, prediction of graft failure based on serology is cumbersome. Although sensitivity and specificity of current solid-phase assays (SPAs) for HLA antibody detection are high, correlation with graft failure remains elusive. When lacking an alternative donor, reduction of strong reacting DSA must be attempted. Unfortunately, results of DSA reduction treatments in HSCT are scarcely reported. Case reports show that persisting DSA after plasmaexchange and immunosuppressive treatment can become negative after a 'last rescue' in vivo absorption with antigen-bearing platelets or donor lymphocyte transfusions. The destruction of engrafting hematopoietic cells by antibodies appears to be an immediate event. Blocking antibody mediated effector functions, e.g. with intravenous immunoglobulin (IvIg), may have additional value, despite IvIg often not reducing the antibody titre. An even less explored aspect of HLA-immunization is the presence of non-DSA antibodies in the host or HLA antibodies emerging post-transplantation. Such antibodies, either causally or as confounders, may be associated with negative transplant outcome. We conclude that HLA antibody assessment should be at the forefront in the treatment handbook of HSCT.

Increased Negative Impact of Donor HLA-Specific Together With Non-HLA–Specific Antibodies on Graft Outcome

Transplantation, 2014

Background. De novo donor HLA-specific (dnDSA) and non-HLA antibodies including antiangiotensin type 1 receptor antibodies (AT 1 R-abs) have been associated with antibody-mediated rejection (AMR) and decreased graft survival as well as cellular-mediated rejection (CMR) and early onset of microvasculopathy in heart transplantation. The aim of our study was to determine the impact of antiYAT 1 R-ab and antiYdonor HLAYspecific antibody (DSA) on clinical outcomes.

Risk and prevention of graft failure in patients with preexisting donor-specific HLA antibodies undergoing unmanipulated haploidentical SCT

Bone Marrow Transplantation, 2011

A role of donor-specific HLA antibodies (DSA) in graft failure after SCT has been suggested, but the relevance of DSA in unmanipulated haploidentical SCT (haplo-SCT) remains unknown. We prospectively examined HLA antibodies using the Luminex-based single Ag assay for 79 adult patients undergoing unmanipulated haplo-SCT. Among them, 16 (20.2%) were HLA Ab-positive, including five patients with antibodies not corresponding to donor HLA Ags and 11 DSA-positive patients. Of the 11 DSA-positive patients, five received treatments to decrease DSA levels, including two, who received plasma exchange and rituximab, two who received platelet transfusions from healthy-related donors having DSAcorresponding HLA Ags and one who received bortezomib. Platelet transfusion was the most simple and effective treatment option for class I DSA. The cumulative incidence of neutrophil recovery was significantly lower in pretransplant (post-treatment) DSA-positive patients than in DSA-negative patients (61.9 vs 94.4%, P ¼ 0.026). Notably, three of five patients with high levels of DSA had graft failure. Donors should be selected on the basis of an evaluation of HLA antibodies. If haplo-SCT from donors with HLA Ags that correspond to high levels of DSA must be performed, then recipients should be treated for DSA to improve the chances of successful donor engraftment.

Donor specific anti-hla antibodies with antibody mediated rejection and long-term outcomes following heart transplantation

The Journal of Heart and Lung Transplantation, 2017

Introduction-Donor specific anti-HLA antibodies (DSA) are common following heart transplantation and are associated with rejection, cardiac allograft vasculopathy (CAV), and mortality. Currently a non-invasive diagnostic test for pathologic AMR (pAMR) does not exist. Methods-221 consecutive adult patients underwent heart transplantation from January 1 st , 2010 through August 31 th , 2013 and followed through October 1 st , 2015. The primary objective was to determine whether the presence of DSA could detect AMR at the time of pathologic diagnosis. Secondary analyses included the association of DSA (stratified by MHC Class and de-novo status) during AMR with new graft dysfunction, graft loss (mortality or retransplantation), and development of CAV. Results-During the study period 69 individual patients (31.2%) had DSA (24% had de-novo DSA) and there were 74 episodes of pAMR in 38 unique patients. The sensitivity of DSA at any MFI to detect concurrent pAMR was only 54.3%. The presence of any DSA during pAMR increased the odds of graft dysfunction (OR 5.37, 95% CI 1.34-21.47, p=0.018), adjusting for age, gender, and timing of AMR. Circulating Class II DSA after transplantation increased the risk of future pAMR (HR 2.97, 95% CI 1.31-6.73, p=0.009). Patients who developed de-novo Class II DSA had a 151% increase in risk of graft loss (contingent on 30-day survival) compared with those who did not have DSA (95% CI 1.11-5.69, p=0.027).