Introduction: After kidney transplantation, rejection and drug-related toxicity occur despite tacrolimus whole blood pre-dose concentrations ([Tac](blood)) being within the target range. The... Show moreIntroduction: After kidney transplantation, rejection and drug-related toxicity occur despite tacrolimus whole blood pre-dose concentrations ([Tac](blood)) being within the target range. The tacrolimus concentration within peripheral blood mononuclear cells ([Tac](cells)) might correlate better with clinical outcomes. The aim of this study was to investigate the correlation between [Tac](blood) and [Tac](cells), the evolution of [Tac](cells) and the [Tac](cells)/[Tac](blood) ratio, and to assess the relationship between tacrolimus concentrations and the occurrence of rejection. Methods: In this prospective study, samples for the measurement of [Tac](blood) and [Tac](cells) were collected on days 3 and 10 after kidney transplantation, and on the morning of a for-cause kidney transplant biopsy. Biopsies were reviewed according to the Banff 2019 update. Results: Eighty-three [Tac](cells) samples were measured of 44 kidney transplant recipients. The correlation between [Tac](cells) and [Tac](blood) was poor (Pearson's r = 0.56 (day 3); r = 0.20 (day 10)). Both the dose-corrected [Tac](cells) and the [Tac](cells)/[Tac](blood) ratio were not significantly different between days 3 and 10, and the median inter-occasion variability of the dose-corrected [Tac](cells) and the [Tac](cells)/[Tac](blood) ratio were 19.4% and 23.4%, respectively (n = 24). Neither [Tac](cells), [Tac](blood), nor the [Tac](cells)/[Tac](blood) ratio were significantly different between patients with biopsy-proven acute rejection (n = 4) and patients with acute tubular necrosis (n = 4) or a cancelled biopsy (n = 9; p > 0.05). Conclusion: Tacrolimus exposure and distribution appeared stable in the early phase after transplantation. [Tac](cells) was not significantly associated with the occurrence of rejection. A possible explanation for these results might be related to the low number of patients included in this study and also due to the fact that PBMCs are not a specific enough matrix to monitor tacrolimus concentrations. Show less
Rojas, A.M.; Gelder, T. van; Kuiper, R. de; Reijerkerk, D.; Clahsen-van Groningen, M.C.; Hesselink, D.A.; ... ; Besouw, N.M. van 2021
Pre-transplant screening focuses on the detection of anti-HLA alloantibodies. Previous studies have shown that IFN-gamma and IL-21 producing T cells are associated with the development of acute... Show morePre-transplant screening focuses on the detection of anti-HLA alloantibodies. Previous studies have shown that IFN-gamma and IL-21 producing T cells are associated with the development of acute rejection (AR). The aim of this study, was to assess whether pre-transplant donor-reactive T cells and/or B cells are associated with increased rejection risk. Samples from 114 kidney transplant recipients (transplanted between 2010 and 2013) were obtained pre-transplantation. The number of donor-reactive IFN-gamma and IL-21 producing cells was analyzed by ELISPOT assay. The presence of donor specific antibodies (DSA) was also determined before transplantation. Numbers of donor-reactive IFN-gamma producing cells were similar in patients with or without AR whereas those of IL-21 producing cells were higher in patients with AR (p = 0.03). Significantly more patients with AR [6/30(20%)] had detectable DSA compared to patients without AR [5/84(5.9%), p = 0.03]. Multivariate logistic regression showed that donor age (OR 1.06), pre-transplant DSA (OR 5.61) and positive IL-21 ELISPOT assay (OR 2.77) were independent predictors of an increased risk for the development of AR. Aside from an advanced donor-age and pre-transplant DSA, also pre-transplant donor-reactive IL-21 producing cells are associated with the development of AR after transplantation. Show less
Francke, M.I.; Andrews, L.M.; H.L. le; Wetering, J. van de; Clahsen-van Groningen, M.C.; Gelder, T. van; ... ; Hesselink, D.A. 2021
Bodyweight-based tacrolimus dosing followed by therapeutic drug monitoring is standard clinical care after renal transplantation. However, after transplantation, a meager 38% of patients are on... Show moreBodyweight-based tacrolimus dosing followed by therapeutic drug monitoring is standard clinical care after renal transplantation. However, after transplantation, a meager 38% of patients are on target at first steady-state and it can take up to 3 weeks to reach the target tacrolimus predose concentration (C-0). Tacrolimus underexposure and overexposure is associated with an increased risk of rejection and drug-related toxicity, respectively. To minimize subtherapeutic and supratherapeutic tacrolimus exposure in the immediate post-transplant phase, a previously developed dosing algorithm to predict an individual's tacrolimus starting dose was tested prospectively. In this single-arm, prospective, therapeutic intervention trial, 60 de novo kidney transplant recipients received a tacrolimus starting dose based on a dosing algorithm instead of a standard, bodyweight-based dose. The algorithm included cytochrome P450 (CYP)3A4 and CYP3A5 genotype, body surface area, and age as covariates. The target tacrolimus C-0, measured for the first time at day 3, was 7.5-12.5 ng/mL. Between February 23, 2019, and July 7, 2020, 60 patients were included. One patient was excluded because of a protocol violation. On day 3 post-transplantation, 34 of 59 patients (58%, 90% CI 47-68%) had a tacrolimus C-0 within the therapeutic range. Markedly subtherapeutic (< 5.0 ng/mL) and supratherapeutic (> 20 ng/mL) tacrolimus concentrations were observed in 7% and 3% of the patients, respectively. Biopsy-proven acute rejection occurred in three patients (5%). In conclusion, algorithm-based tacrolimus dosing leads to the achievement of the tacrolimus target C-0 in as many as 58% of the patients on day 3 after kidney transplantation. Show less
Aims: Chronic-active antibody mediated rejection (c-aABMR) is a major cause of kidney graft loss. Currently, little is known about the relation between histopathologic parameters and renal... Show moreAims: Chronic-active antibody mediated rejection (c-aABMR) is a major cause of kidney graft loss. Currently, little is known about the relation between histopathologic parameters and renal allograft survival.Methods and results: Between 2008 and 2014, 41 patients with a progressive decrease in renal function were diagnosed with c-aABMR according to Banff 2015 and followed up for at least 3 years. Clinical and renal biopsy characteristics were analyzed for association with graft survival.During follow-up 26 cases lost their graft because of c-aABMR at a median follow up of 40 months after diagnosis.Cases with v-lesions in their biopsy had a significant higher loss of eGFR prior to diagnosis. The total inflammation score (r = -0.45 p = .007) and the severity of interstitial fibrosis (r = -0.38 p = .023) were related to the eGFR at time of biopsy.Univariate regression analysis showed that eGFR at time of biopsy, total inflammation, interstitial fibrosis and the sum chronicity score were significantly related to the risk for graft failure during follow-up. In a multivariate analysis only the severity of interstitial fibrosis remained associated with decreased graft survival (HR 1.9 per score point, 95% CI 1.2-2.8, p = .004).Conclusion: Severity of renal interstitial fibrosis and not inflammation predicts graft survival in cases of c-aABMR. Show less
Leur, K. de; Dieterich, M.; Hesselink, D.A.; Corneth, O.B.J.; Dor, F.J.M.F.; Graav, G.N. de; ... ; Baan, C.C. 2019
Tissue-resident memory T (T-RM) cells are characterized by their surface expression of CD69 and can be subdivided in CD103+ and CD103-T-RM cells. The origin and functional characteristics of T-RM... Show moreTissue-resident memory T (T-RM) cells are characterized by their surface expression of CD69 and can be subdivided in CD103+ and CD103-T-RM cells. The origin and functional characteristics of T-RM cells in the renal allograft are largely unknown. To determine these features we studied T-RM cells in transplant nephrectomies. T-RM cells with a CD103+ and CD103-phenotype were present in all samples (n = 13) and were mainly CD8+ T cells. Of note, donor-derived T-RM cells were only detectable in renal allografts that failed in the first month after transplantation. Grafts, which failed later, mainly contained recipient derived T-RM cells. The gene expression profiles of the recipient derived CD8+ T-RM cells were studied in more detail and showed a previously described signature of tissue residence within both CD103+ and CD103-T-RM cells. All CD8+ T-RM cells had strong effector abilities through the production of IFN gamma and TNF alpha, and harboured high levels of intracellular granzyme B and low levels of perforin. In conclusion, our results demonstrate that donor and recipient T-RM cells reside in the rejected renal allograft. Over time, the donor-derived T-RM cells are replaced by recipient T-RM cells which have features that enables these cells to aggressively respond to the allograft. Show less
Background: Molecules of the innate immune response are increasingly recognized as important mediators in allograft injury during and after kidney transplantation. We therefore aimed to establish... Show moreBackground: Molecules of the innate immune response are increasingly recognized as important mediators in allograft injury during and after kidney transplantation. We therefore aimed to establish the relationship between the expression of these genes at implantation, during an acute rejection (AR) and on graft outcome.Method: A total of 19 genes, including Toll like receptors (TLRs), complement components and regulators, and apoptosis-related genes were analyzed at the mRNA level by qPCR in 123 biopsies with acute rejection and paired pre-transplantation tissue (n=75). Results: Before transplantation, relative mRNA expression of BAX:BCL2 ratio (apoptosis marker) and several complement genes was significantly higher in tissue samples from deceased donors compared to living donors. During AR, TLRs and complement genes showed an increased expression compared to pre-transplant conditions, whereas complement regulators were decreased. A relatively high TLR4 expression level and BAX:BCL2 ratio during AR in the deceased donor group was associated with adverse graft outcome, independently of clinical risk factors. Conclusions: Complement- and apoptosis-related gene expression is elevated in deceased donor transplants before transplantation. High BAX:BCL2 ratio and TLR4 expression during AR may reflect enhanced intragraft cell death and immunogenic danger signals, and pose a risk factor for adverse graft outcome. Show less
Background. Belatacept, an inhibitor of the CD28-CD80/86 costimulatory pathway, allows for calcineurin-inhibitor free immunosuppressive therapy in kidney transplantation but is associated with a... Show moreBackground. Belatacept, an inhibitor of the CD28-CD80/86 costimulatory pathway, allows for calcineurin-inhibitor free immunosuppressive therapy in kidney transplantation but is associated with a higher acute rejection risk than ciclosporin. Thus far, no biomarker for belatacept-resistant rejection has been validated. In this randomized-controlled trial, acute rejection rate was compared between belatacept-and tacrolimus-treated patients and immunological biomarkers for acute rejection were investigated. Methods. Forty kidney transplant recipients were 1:1 randomized to belatacept or tacrolimus combined with basiliximab, mycophenolate mofetil, and prednisolone. The 1-year incidence of biopsy-proven acute rejection was monitored. Potential biomarkers, namely, CD8(+) CD28(-), CD4(+) CD57(+) PD1(-), and CD8(+) CD28(++) end-stage terminally differentiated memory T cells were measured pretransplantation and posttranspla(n)tation and correlated to rejection. Pharmacodynamic monitoring of belatacept was performed by measuring free CD86 on monocytes. Results. The rejection incidence was higher in belatacept-treated than tacrolimus-treated patients: 55% versus 10% (P = 0.006). All 3 graft losses, due to rejection, occurred in the belatacept group. Although 4 of 5 belatacept-treated patients with greater than 35 cells CD8(+) CD28(++) end-stage terminally differentiated memory T cells/mu L rejected, median pretransplant values of the biomarkers did not differ between belatacept-treated rejectors and nonrejectors. In univariable Cox regressions, the studied cell subsets were not associated with rejection-risk. CD86 molecules on circulating monocytes in belatacept-treated patients were saturated at all timepoints. Conclusions. Belatacept-based immunosuppressive therapy resulted in higher and more severe acute rejection compared with tacrolimus-based therapy. This trial did not identify cellular biomarkers predictive of rejection. In addition, the CD28-CD80/86 costimulatory pathway appeared to be sufficiently blocked by belatacept and did not predict rejection. Show less
Rekers, N.V.; Flaig, T.M.; Mallat, M.J.K.; Spruyt-Gerritse, M.J.; Zandbergen, M.; Anholts, J.D.H.; ... ; Eikmans, M. 2017
