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Evaluation of Ca2+ Binding Sites in Tacrolimus by Infrared Multiple Photon Dissociation Spectroscopy.
Masson, MAC, Karpfenstein, R, de Oliveira-Silva, D, Teuler, JM, Archirel, P, Maître, P, Correra, TC
The journal of physical chemistry. B. 2018;(43):9860-9868
Abstract
Tacrolimus (TAC) is an efficient immunosuppressant used in organ transplantation procedures. There is an intrinsic correlation between TAC and Ca2+ because of the dependence of its action mechanism on calcium and calcineurin, and the role of ion coordination on TAC identification and quantitation. To depict the Ca2+ binding sites in TAC, this work carried out gas-phase vibrational infrared multiple photon dissociation spectroscopy of [Ca(TAC)]2+ and of three other TAC mimetic molecules (probes 1-3). Density functional theory (DFT) and Monte Carlo (MC) simulations were also used to support the experimental data assignment, and natural bond orbital (NBO) analysis was carried out to depict the coordination sphere. PM3 and B3LYP/6-31G(d) levels of theory displayed similar trends during the MC simulations, suggesting that PM3 is a viable alternative to more expensive DFT calculations, at least during the conformational analysis step. Infrared spectroscopy of the [Ca(probe X)1]2+ and [Ca(probe X)3]2+ ( X = 1-3) complexes allowed for a useful guide for building guess geometries and for the band assignment of the [Ca(TAC)]2+ complex. Nevertheless, the MC approach was particularly useful for exploring the potential energy surface. The lowest energy conformation for [Ca(TAC)]2+ was found by MC simulations and is 32.92 kJ mol-1 lower in energy than the one found by comparing the results obtained for Ca2+ coordination in probes, despite the calculated spectra being virtually identical. Both approaches are good ways to depict the coordination sites, and these results suggest that using small molecules as models is a reliable approach to depict the geometry or coordination sites of extensive ions, yielding a robust correlation between experimental and theoretical spectra. Furthermore, MC survey produced a lower energy conformation with a good match to the experimental results. Both methods depict the Ca2+ coordination sphere as a hexacoordinated environment where the main coordination centers are carbonyl groups.
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Analysis of NFATc1 amplification in T cells for pharmacodynamic monitoring of tacrolimus in kidney transplant recipients.
Kannegieter, NM, Hesselink, DA, Dieterich, M, de Graav, GN, Kraaijeveld, R, Baan, CC
PloS one. 2018;(7):e0201113
Abstract
BACKGROUND Therapeutic drug monitoring (TDM) of tacrolimus, based on blood concentrations, shows an imperfect correlation with the occurrence of rejection. Here, we tested whether measuring NFATc1 amplification, a member of the calcineurin pathway, is suitable for TDM of tacrolimus. MATERIALS AND METHODS NFATc1 amplification was monitored in T cells of kidney transplant recipients who received either tacrolimus- (n = 11) or belatacept-based (n = 10) therapy. Individual drug effects on NFATc1 amplification were studied in vitro, after spiking blood samples of healthy volunteers with either tacrolimus, belatacept or mycophenolate mofetil. RESULTS At day 30 after transplantation, in tacrolimus-treated patients, NFATc1 amplification was inhibited in CD4+ T cells expressing the co-stimulation receptor CD28 (mean inhibition 37%; p = 0.01) and in CD8+CD28+ T cells (29% inhibition; p = 0.02), while this was not observed in CD8+CD28- T cells or belatacept-treated patients. Tacrolimus pre-dose concentrations of these patients correlated inversely with NFATc1 amplification in CD28+ T cells (rs = -0.46; p < 0.01). In vitro experiments revealed that 50 ng/ml tacrolimus affected NFATc1 amplification by 58% (mean; p = 0.02). CONCLUSION In conclusion, measuring NFATc1 amplification is a direct tool for monitoring biological effects of tacrolimus on T cells in whole blood samples of kidney transplant recipients. This technique has potential that requires further development before it can be applied in daily practice.
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3.
Morphea and Eosinophilic Fasciitis: An Update.
Mertens, JS, Seyger, MMB, Thurlings, RM, Radstake, TRDJ, de Jong, EMGJ
American journal of clinical dermatology. 2017;(4):491-512
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Abstract
Morphea, also known as localized scleroderma, encompasses a group of idiopathic sclerotic skin diseases. The spectrum ranges from relatively mild phenotypes, which generally cause few problems besides local discomfort and visible disfigurement, to subtypes with severe complications such as joint contractures and limb length discrepancies. Eosinophilic fasciitis (EF, Shulman syndrome) is often regarded as belonging to the severe end of the morphea spectrum. The exact driving mechanisms behind morphea and EF pathogenesis remain to be elucidated. However, extensive extracellular matrix formation and autoimmune dysfunction are thought to be key pathogenic processes. Likewise, these processes are considered essential in systemic sclerosis (SSc) pathogenesis. In addition, similarities in clinical presentation between morphea and SSc have led to many theories about their relatedness. Importantly, morphea may be differentiated from SSc based on absence of sclerodactyly, Raynaud's phenomenon, and nailfold capillary changes. The diagnosis of morphea is often based on characteristic clinical findings. Histopathological evaluation of skin biopsies and laboratory tests are not necessary in the majority of morphea cases. However, full-thickness skin biopsies, containing fascia and muscle tissue, are required for the diagnosis of EF. Monitoring of disease activity and damage, especially of subcutaneous involvement, is one of the most challenging aspects of morphea care. Therefore, data harmonization is crucial for optimizing standard care and for comparability of study results. Recently, the localized scleroderma cutaneous assessment tool (LoSCAT) has been developed and validated for morphea. The LoSCAT is currently the most widely reported outcome measure for morphea. Care providers should take disease subtype, degree of activity, depth of involvement, and quality-of-life impairments into account when initiating treatment. In most patients with circumscribed superficial subtypes, treatment with topical therapies suffices. In more widespread disease, UVA1 phototherapy or systemic treatment with methotrexate (MTX), with or without a systemic corticosteroid combination, should be initiated. Disappointingly, few alternatives for MTX have been described and additional research is still needed to optimize treatment for these debilitating conditions. In this review, we present a state-of-the-art flow chart that guides care providers in the treatment of morphea and EF.
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Differential T Cell Signaling Pathway Activation by Tacrolimus and Belatacept after Kidney Transplantation: Post Hoc Analysis of a Randomised-Controlled Trial.
Kannegieter, NM, Hesselink, DA, Dieterich, M, de Graav, GN, Kraaijeveld, R, Baan, CC
Scientific reports. 2017;(1):15135
Abstract
Pharmacokinetic immunosuppressive drug monitoring poorly correlates with clinical outcomes after solid organ transplantation. A promising method for pharmacodynamic monitoring of tacrolimus (TAC) in T cell subsets of transplant recipients might be the measurement of (phosphorylated) p38MAPK, ERK1/2 and Akt (activated downstream of the T cell receptor) by phospho-specific flow cytometry. Here, blood samples from n = 40 kidney transplant recipients (treated with either TAC-based or belatacept (BELA)-based immunosuppressive drug therapy) were monitored before and throughout the first year after transplantation. After transplantation and in unstimulated samples, p-p38MAPK and p-Akt were inhibited in CD8+ T cells and p-ERK in CD4+ T cells but only in patients who received TAC-based therapy. After activation with PMA/ionomycin, p-p38MAPK and p-AKT were significantly inhibited in CD4+ and CD8+ T cells when TAC was given, compared to pre-transplantation. Eleven BELA-treated patients had a biopsy-proven acute rejection, which was associated with higher p-ERK levels in both CD4+ and CD8+ T cells compared to patients without rejection. In conclusion, phospho-specific flow cytometry is a promising tool to pharmacodynamically monitor TAC-based therapy. In contrast to TAC-based therapy, BELA-based immunosuppression does not inhibit key T cell activation pathways which may contribute to the high rejection incidence among BELA-treated transplant recipients.
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A Randomized Controlled Clinical Trial Comparing Belatacept With Tacrolimus After De Novo Kidney Transplantation.
de Graav, GN, Baan, CC, Clahsen-van Groningen, MC, Kraaijeveld, R, Dieterich, M, Verschoor, W, von der Thusen, JH, Roelen, DL, Cadogan, M, van de Wetering, J, et al
Transplantation. 2017;(10):2571-2581
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Abstract
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 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, CD8CD28, CD4CD57PD1, and CD8CD28 end-stage terminally differentiated memory T cells were measured pretransplantation and posttransplantation 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 CD8CD28 end-stage terminally differentiated memory T cells/μL 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.
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Tacrolimus eye drops as monotherapy for vernal keratoconjunctivitis: a randomized controlled trial.
Müller, EG, Santos, MSD, Freitas, D, Gomes, JÁP, Belfort, R
Arquivos brasileiros de oftalmologia. 2017;(3):154-158
Abstract
PURPOSE To assess the efficacy of monotherapy using tacrolimus eye drops versus sodium cromoglycate for the treatment of vernal keratoconjunctivitis (VKC). METHODS Randomized double-masked controlled trial comparing the efficacy of tacrolimus 0.03% eye drops t.i.d. (Group 1) with sodium cromoglycate 4% eye drops t.i.d. (Group 2) for the symptomatic control of VKC at days 0, 15, 30, 45, and 90 of follow-up. Visual acuity, intraocular pressure, and other complications were evaluated to assess safety and side effects. RESULTS In total, 16 patients were included, with 8 enrolled in each group. Two patients from Group 2 were excluded from the analysis at days 45 and 90 because of corticosteroid use. Most patients were male (81.8%) and presented with limbal VKC (56.3%). There were statistically significant differences in favor of tacrolimus in the following severity scores: itching at day 90 (p=0.001); foreign body sensation at day 15 (p=0.042); photophobia at day 30 (p=0.041); keratitis at day 30 (p=0.048); and limbal activity at days 15 (p=0.011), 30 (p=0.007), and 45 (p=0.015). No relevant adverse effects were reported, except for a burning sensation with tacrolimus, though this did not compromise treatment compliance. CONCLUSION Treatment with tacrolimus was superior to sodium cromoglycate when comparing severity scores for symptoms of itching, foreign body sensation, and photophobia, as well as for signs of limbal inflammatory activity and keratitis.
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Incidence of Posttransplantation Diabetes Mellitus in De Novo Kidney Transplant Recipients Receiving Prolonged-Release Tacrolimus-Based Immunosuppression With 2 Different Corticosteroid Minimization Strategies: ADVANCE, A Randomized Controlled Trial.
Mourad, G, Glyda, M, Albano, L, Viklický, O, Merville, P, Tydén, G, Mourad, M, Lõhmus, A, Witzke, O, Christiaans, MHL, et al
Transplantation. 2017;(8):1924-1934
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Abstract
BACKGROUND ADVANCE (NCT01304836) was a phase 4, multicenter, prospectively randomized, open-label, 24-week study comparing the incidence of posttransplantation diabetes mellitus (PTDM) with 2 prolonged-release tacrolimus corticosteroid minimization regimens. METHODS All patients received prolonged-release tacrolimus, basiliximab, mycophenolate mofetil and 1 bolus of intraoperative corticosteroids (0-1000 mg) as per center policy. Patients in arm 1 received tapered corticosteroids, stopped after day 10, whereas patients in arm 2 received no steroids after the intraoperative bolus. The primary efficacy variable was the diagnosis of PTDM as per American Diabetes Association criteria (2010) at any point up to 24 weeks postkidney transplantation. Secondary efficacy variables included incidence of composite efficacy failure (graft loss, biopsy-proven acute rejection or severe graft dysfunction: estimated glomerular filtration rate (Modification of Diet in Renal Disease-4) <30 mL/min per 1.73 m), acute rejection and graft and patient survival. RESULTS The full-analysis set included 1081 patients (arm 1: n = 528, arm 2: n = 553). Baseline characteristics and mean tacrolimus trough levels were comparable between arms. Week 24 Kaplan-Meier estimates of PTDM were similar for arm 1 versus arm 2 (17.4% vs 16.6%; P = 0.579). Incidence of composite efficacy failure, graft and patient survival, and mean estimated glomerular filtration rate were also comparable between arms. Biopsy-proven acute rejection and acute rejection were significantly higher in arm 2 versus arm 1 (13.6% vs 8.7%, P = 0.006 and 25.9% vs 18.2%, P = 0.001, respectively). Tolerability profiles were comparable between arms. CONCLUSIONS A prolonged-release tacrolimus, basiliximab, and mycophenolate mofetil immunosuppressive regimen is efficacious, with a low incidence of PTDM and a manageable tolerability profile over 24 weeks of treatment. A lower incidence of biopsy-proven acute rejection was seen in patients receiving corticosteroids tapered over 10 days plus an intraoperative corticosteroid bolus versus those receiving an intraoperative bolus only.
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Automated Reminders and Physician Notification to Promote Immunosuppression Adherence Among Kidney Transplant Recipients: A Randomized Trial.
Reese, PP, Bloom, RD, Trofe-Clark, J, Mussell, A, Leidy, D, Levsky, S, Zhu, J, Yang, L, Wang, W, Troxel, A, et al
American journal of kidney diseases : the official journal of the National Kidney Foundation. 2017;(3):400-409
Abstract
BACKGROUND Immunosuppression nonadherence increases the risk for kidney transplant loss after transplantation. Wireless-enabled pill bottles have created the opportunity to monitor medication adherence in real time. Reminders may help patients with poor memory or organization. Provision of adherence data to providers may motivate patients to improve adherence and help providers identify adherence barriers. STUDY DESIGN Randomized controlled trial. SETTING & PARTICIPANTS Kidney transplant recipients (n=120) at a single center. INTERVENTION Participants were provided wireless pill bottles to store tacrolimus and record bottle openings. Participants were randomly assigned 1:1:1 to adherence monitoring with customized reminders (including alarms, texts, telephone calls, and/or e-mails), monitoring with customized reminders plus provider notification (every 2 weeks, providers received notification if adherence decreased to <90% during that period), or wireless pill bottle use alone (control). OUTCOMES The main outcome was bottle-measured tacrolimus adherence during the last 90 days of the 180-day trial. A secondary outcome was tacrolimus whole-blood concentrations at routine clinical visits. MEASUREMENTS Adherence for the primary outcome was assessed via wireless pill bottle openings. RESULTS Mean participant age was 50 years; 60% were men, and 40% were black. Mean adherence was 78%, 88%, and 55% in the reminders, reminders-plus-notification, and control arms (P<0.001 for comparison of each intervention to control). Mean tacrolimus levels were not significantly different between groups. LIMITATIONS The study did not assess clinical end points. Participants and study coordinators were not blinded to intervention arm. CONCLUSIONS Provider notification and customized reminders appear promising in helping patients achieve better medication adherence, but these strategies require evaluation in trials powered to detect differences in clinical outcomes.
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Efficacy and Safety of Everolimus and Mycophenolic Acid With Early Tacrolimus Withdrawal After Liver Transplantation: A Multicenter Randomized Trial.
Saliba, F, Duvoux, C, Gugenheim, J, Kamar, N, Dharancy, S, Salamé, E, Neau-Cransac, M, Durand, F, Houssel-Debry, P, Vanlemmens, C, et al
American journal of transplantation : official journal of the American Society of Transplantation and the American Society of Transplant Surgeons. 2017;(7):1843-1852
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Abstract
SIMCER was a 6-mo, multicenter, open-label trial. Selected de novo liver transplant recipients were randomized (week 4) to everolimus with low-exposure tacrolimus discontinued by month 4 (n = 93) or to tacrolimus-based therapy (n = 95), both with basiliximab induction and enteric-coated mycophenolate sodium with or without steroids. The primary end point, change in estimated GFR (eGFR; MDRD formula) from randomization to week 24 after transplant, was superior with everolimus (mean eGFR change +1.1 vs. -13.3 mL/min per 1.73 m2 for everolimus vs. tacrolimus, respectively; difference 14.3 [95% confidence interval 7.3-21.3]; p < 0.001). Mean eGFR at week 24 was 95.8 versus 76.0 mL/min per 1.73 m2 for everolimus versus tacrolimus (p < 0.001). Treatment failure (treated biopsy-proven acute rejection [BPAR; rejection activity index score >3], graft loss, or death) from randomization to week 24 was similar (everolimus 10.0%, tacrolimus 4.3%; p = 0.134). BPAR was more frequent between randomization and month 6 with everolimus (10.0% vs. 2.2%; p = 0.026); the rate of treated BPAR was 8.9% versus 2.2% (p = 0.055). Sixteen everolimus-treated patients (17.8%) and three tacrolimus-treated patients (3.2%) discontinued the study drug because of adverse events. In conclusion, early introduction of everolimus at an adequate exposure level with gradual calcineurin inhibitor (CNI) withdrawal after liver transplantation, supported by induction therapy and mycophenolic acid, is associated with a significant renal benefit versus CNI-based immunosuppression but more frequent BPAR.
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Efficacy and safety of tacrolimus compared with ciclosporin-A in renal transplantation: 7-year observational results.
Krämer, BK, Montagnino, G, Krüger, B, Margreiter, R, Olbricht, CJ, Marcen, R, Sester, U, Kunzendorf, U, Dietl, KH, Rigotti, P, et al
Transplant international : official journal of the European Society for Organ Transplantation. 2016;(3):307-14
Abstract
The European Tacrolimus versus Ciclosporin-A Microemulsion (CsA-ME) Renal Transplantation Study demonstrated that tacrolimus decreased acute rejection rates at 6 months. Primary endpoints of this investigator-initiated, observational 7-year follow-up study were acute rejection rates, patient and graft survival rates, and a composite endpoint (BPAR, graft loss, and patient death). We analyzed data from the original intent-to-treat population (n = 557; 286 tacrolimus, 271 CsA-ME). A total of 237 tacrolimus and 208 CsA-ME patients provided data. At 7 years, Kaplan-Meier estimated rates of patients free from BPAR were 77.1% in the tacrolimus arm and 59.9% in the CsA-ME arm, graft survival rates amounted to 82.6% and 80.6%, and patient survival rates to 89.9% and 88.1%. Estimated combined endpoint-free survival rates were 60.2% in the tacrolimus arm and 47.0% in the CsA-ME arm (P = <0.0001). A higher number of patients from the CsA-ME arm crossed over to tacrolimus during 7 year follow-up: 19.7% vs. 7.9% (P = <0.002). More patients in the tacrolimus group stopped steroids and received immunosuppressive monotherapy. Significantly, more CsA-ME patients received lipid-lowering medication and experienced cosmetic and cardiovascular adverse events. Tacrolimus-treated renal transplant recipients had significantly higher combined endpoint-free survival rates mainly driven by lower acute rejection rates despite less immunosuppressive medication at 7 years.