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An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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Lupus nephritis is a potentially fatal autoimmune disease for which the current treatment is ineffective and often toxic. To develop mechanistic hypotheses of disease, we analyzed kidney samples from patients with lupus nephritis and from healthy control subjects using single-cell RNA sequencing. Our analysis revealed 21 subsets of leukocytes active in disease, including multiple populations of myeloid cells, T cells, natural killer cells and B cells that demonstrated both pro-inflammatory responses and inflammation-resolving responses. We found evidence of local activation of B cells correlated with an age-associated B-cell signature and evidence of progressive stages of monocyte differentiation within the kidney. A clear interferon response was observed in most cells. Two chemokine receptors, CXCR4 and CX3CR1, were broadly expressed, implying a potentially central role in cell trafficking. Gene expression of immune cells in urine and kidney was highly correlated, which would suggest that urine might serve as a surrogate for kidney biopsies.
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Riñón/inmunología , Nefritis Lúpica/inmunología , Biomarcadores , Biopsia , Análisis por Conglomerados , Biología Computacional/métodos , Células Epiteliales/metabolismo , Citometría de Flujo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Humanos , Inmunofenotipificación , Interferones/metabolismo , Riñón/metabolismo , Riñón/patología , Leucocitos/inmunología , Leucocitos/metabolismo , Nefritis Lúpica/genética , Nefritis Lúpica/metabolismo , Nefritis Lúpica/patología , Linfocitos/inmunología , Linfocitos/metabolismo , Anotación de Secuencia Molecular , Células Mieloides/inmunología , Células Mieloides/metabolismo , Análisis de la Célula Individual , TranscriptomaRESUMEN
The proteasome inhibitor bortezomib (BTZ) is proposed to deplete activated B cells and plasma cells. However, a complete picture of the mechanisms underlying BTZ-induced apoptosis in B lineage cells remains to be established. In this study, using a direct in vitro approach, we show that deletion of the tumor suppressor and cell cycle regulator p53 rescues recently activated mouse B cells from BTZ-induced apoptosis. Furthermore, BTZ treatment elevated intracellular p53 levels, and p53 deletion constrained apoptosis, as recently stimulated cells first transitioned from the G1 to S phase of the cell cycle. Moreover, combined inhibition of the p53-associated cell cycle regulators and E3 ligases MDM2 and anaphase-promoting complex/cyclosome induced cell death in postdivision B cells. Our results reveal that efficient cell cycle progression of activated B cells requires proteasome-driven inhibition of p53. Consequently, BTZ-mediated interference of proteostasis unleashes a p53-dependent cell cycle-associated death mechanism in recently activated B cells.
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Antineoplásicos , Inhibidores de Proteasoma , Animales , Ratones , Bortezomib/farmacología , Bortezomib/metabolismo , Inhibidores de Proteasoma/farmacología , Antineoplásicos/farmacología , Proteína p53 Supresora de Tumor/metabolismo , Línea Celular Tumoral , Complejo de la Endopetidasa Proteasomal/metabolismo , ApoptosisRESUMEN
Solid organ transplantation is a life-saving procedure for patients with end-stage organ disease. Over the past 70 years, tremendous progress has been made in solid organ transplantation, particularly in T-cell-targeted immunosuppression and organ allocation systems. However, humoral alloimmune responses remain a major challenge to progress. Patients with preexisting antibodies to human leukocyte antigen (HLA) are at significant disadvantages in regard to receiving a well-matched organ, moreover, those who develop anti-HLA antibodies after transplantation face a significant foreshortening of renal allograft survival. Historical therapies to desensitize patients prior to transplantation or to treat posttransplant AMR have had limited effectiveness, likely because they do not significantly reduce antibody levels, as plasma cells, the source of antibody production, remain largely unaffected. Herein, we will discuss the significance of plasma cells in transplantation, aspects of their biology as potential therapeutic targets, clinical challenges in developing strategies to target plasma cells in transplantation, and lastly, novel approaches that have potential to advance the field.
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Trasplante de Riñón , Rechazo de Injerto , Antígenos HLA , Humanos , Isoanticuerpos , Células PlasmáticasRESUMEN
To date, plasma cell (PC)-targeted therapies have been limited by suboptimal PC depletion and antibody rebound. We hypothesized this is partly because of PC residence in protective bone marrow (BM) microenvironments. The purpose of this proof-of-concept study was to examine the effects of the CXCR4 antagonist, plerixafor, on PC BM residence; its safety profile (alone and in combination with a proteasome inhibitor, bortezomib); and the transcriptional effect on BMPCs in HLA-sensitized kidney transplant candidates. Participants were enrolled into 3 groups: group A (n = 4), plerixafor monotherapy; and groups B (n = 4) and C (n = 4), plerixafor and bortezomib combinations. CD34+ stem cell and PC levels increased in the blood after plerixafor treatment. PC recovery from BM aspirates varied depending on the dose of plerixafor and bortezomib. Single-cell RNA sequencing on BMPCs from 3 group C participants pretreatment and posttreatment revealed multiple populations of PCs, with a posttreatment enrichment of oxidative phosphorylation, proteasome assembly, cytoplasmic translation, and autophagy-related genes. Murine studies demonstrated dually inhibiting the proteasome and autophagy resulted in greater BMPC death than did monotherapies. In conclusion, this pilot study revealed anticipated effects of combined plerixafor and bortezomib on BMPCs, an acceptable safety profile, and suggests the potential for autophagy inhibitors in desensitization regimens.
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Compuestos Heterocíclicos , Trasplante de Riñón , Humanos , Animales , Ratones , Bortezomib/farmacología , Bortezomib/uso terapéutico , Células Plasmáticas , Médula Ósea , Complejo de la Endopetidasa Proteasomal , Ácidos Borónicos/farmacología , Ácidos Borónicos/uso terapéutico , Pirazinas/farmacología , Pirazinas/uso terapéutico , Movilización de Célula Madre Hematopoyética , Proyectos Piloto , Compuestos Heterocíclicos/farmacología , Inhibidores de Proteasoma/farmacología , Inhibidores de Proteasoma/uso terapéutico , Receptores CXCR4RESUMEN
BACKGROUND: To date, the evidence for proteasome-inhibitor (PI) based antibody mediated rejection (AMR) therapy has been with the first-generation PI bortezomib. Results have demonstrated encouraging efficacy for early AMR with lesser efficacy for late AMR. Unfortunately, bortezomib is associated with dose-limiting adverse effects in some patients. We report use of the second generation proteosome inhibitor carfilzomib for AMR treatment in two pediatric patients with a kidney transplant. METHODS: The clinical data on two patients who experienced dose limiting toxicities from bortezomib were collected along with their short- and long-term outcomes. RESULTS: A two-year-old female with simultaneous AMR, multiple de novo DSAs (DR53 MFI 3900, DQ9 MFI 6600, DR15 2200, DR51 MFI 1900) and T-cell mediated rejection (TCMR) completed three carfilzomib cycles and experienced stage 1 acute kidney injury after the first two cycles. At 1 year follow up, all DSAs resolved, and her kidney function returned to baseline without recurrence. A 17-year-old female also developed AMR with multiple de novo DSAs (DQ5 MFI 9900, DQ6 MFI 9800, DQA*01 MFI 9900). She completed two carfilzomib cycles, which were associated with acute kidney injury. She had resolution of rejection on biopsy and decreased but persistent DSAs on follow-up. CONCLUSIONS: Carfilzomib treatment for bortezomib-refractory rejection and/or bortezomib toxicity may provide DSA elimination or reduction, but also appears to be associated with nephrotoxicity. Clinical development of carfilzomib for AMR will require a better understanding of efficacy and development of approaches to mitigate nephrotoxicity.
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BACKGROUND: Kidney transplant recipients are at increased risk of severe outcomes during COVID-19. Antibodies against the virus are thought to offer protection, but a thorough characterization of anti-SARS-CoV-2 immune globulin isotypes in kidney transplant recipients following SARS-CoV-2 infection has not been reported. METHODS: We performed a cross-sectional study of 49 kidney transplant recipients and 42 immunocompetent controls at early (≤14 days) or late (>14 days) time points after documented SARS-CoV-2 infection. Using a validated semiquantitative Luminex-based multiplex assay, we determined the abundances of IgM, IgG, IgG1-4, and IgA antibodies against five distinct viral epitopes. RESULTS: Kidney transplant recipients showed lower levels of total IgG antitrimeric spike (S), S1, S2, and receptor binding domain (RBD) but not nucleocapsid (NC) at early versus late time points after SARS-CoV-2 infection. Early levels of IgG antispike protein epitopes were also lower than in immunocompetent controls. Anti-SARS-CoV-2 antibodies were predominantly IgG1 and IgG3, with modest class switching to IgG2 or IgG4 in either cohort. Later levels of IgG antispike, S1, S2, RBD, and NC did not significantly differ between cohorts. There was no significant difference in the kinetics of either IgM or IgA antispike, S1, RBD, or S2 on the basis of timing after diagnosis or transplant status. CONCLUSIONS: Kidney transplant recipients mount early anti-SARS-CoV-2 IgA and IgM responses, whereas IgG responses are delayed compared with immunocompetent individuals. These findings might explain the poor outcomes in transplant recipients with COVID-19. PODCAST: This article contains a podcast at https://www.asn-online.org/media/podcast/JASN/2021_11_23_briggsgriffin112321.mp3.
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COVID-19 , Receptores de Trasplantes , Humanos , Estudios Transversales , SARS-CoV-2 , Inmunoglobulina G , Anticuerpos Antivirales , Epítopos , Inmunoglobulina MRESUMEN
Kidney transplant recipients administered belatacept-based maintenance immunosuppression present with a more favorable metabolic profile, reduced incidence of de novo donor-specific antibodies (DSAs), and improved renal function and long-term patient/graft survival relative to individuals receiving calcineurin inhibitor (CNI)-based immunosuppression. However, the rates and severity of acute rejection (AR) are greater with the approved belatacept-based regimen than with CNI-based immunosuppression. Although these early co-stimulation blockade-resistant rejections are typically steroid sensitive, the higher rate of cellular AR has led many transplant centers to adopt immunosuppressive regimens that differ from the approved label. This article summarizes the available data on these alternative de novo belatacept-based maintenance regimens. Steroid-sparing, belatacept-based immunosuppression (following T cell-depleting induction therapy) has been shown to yield AR rates comparable to those seen with CNI-based regimens. Concomitant treatment with belatacept plus a mammalian target of rapamycin inhibitor (mTORi; sirolimus or everolimus) has yielded AR rates ranging from 0 to 4%. Because the optimal induction agent and number of induction doses; blood levels of mTORi; and dose, duration, and use of corticosteroids have yet to be determined, larger prospective clinical trials are needed to establish the optimal alternative belatacept-based regimen for minimizing early cellular AR occurrence.
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Trasplante de Riñón , Abatacept/uso terapéutico , Inhibidores de la Calcineurina , Rechazo de Injerto/tratamiento farmacológico , Rechazo de Injerto/etiología , Rechazo de Injerto/prevención & control , Supervivencia de Injerto , Humanos , Terapia de Inmunosupresión , Inmunosupresores/uso terapéutico , Estudios Prospectivos , Receptores de TrasplantesRESUMEN
Patients undergoing evaluation for solid organ transplantation (SOT) frequently have a history of malignancy. Only patients with treated cancer are considered for SOT but the benefits of transplantation need to be balanced against the risk of tumor recurrence, taking into consideration the potential effects of immunosuppression. Prior guidelines on timing to transplant in patients with a prior treated malignancy do not account for current staging, disease biology, or advances in cancer treatments. To update these recommendations, the American Society of Transplantation (AST) facilitated a consensus workshop to comprehensively review contemporary literature regarding cancer therapies, cancer stage specific prognosis, the kinetics of cancer recurrence, as well as the limited data on the effects of immunosuppression on cancer-specific outcomes. This document contains prognosis, treatment, and transplant recommendations for melanoma and hematological malignancies. Given the limited data regarding the risk of cancer recurrence in transplant recipients, the goal of the AST-sponsored conference and the consensus documents produced are to provide expert opinion recommendations that help in the evaluation of patients with a history of a pretransplant malignancy for transplant candidacy.
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Neoplasias Hematológicas , Melanoma , Trasplante de Órganos , Consenso , Testimonio de Experto , Humanos , Recurrencia Local de Neoplasia , PronósticoRESUMEN
Patients undergoing evaluation for solid organ transplantation (SOT) often have a history of malignancy. Although the cancer has been treated in these patients, the benefits of transplantation need to be balanced against the risk of tumor recurrence, especially in the setting of immunosuppression. Prior guidelines of when to transplant patients with a prior treated malignancy do not take in to account current staging, disease biology, or advances in cancer treatments. To develop contemporary recommendations, the American Society of Transplantation held a consensus workshop to perform a comprehensive review of current literature regarding cancer therapies, cancer stage-specific prognosis, the kinetics of cancer recurrence, and the limited data on the effects of immunosuppression on cancer-specific outcomes. This document contains prognosis based on contemporary treatment and transplant recommendations for breast, colorectal, anal, urological, gynecological, and nonsmall cell lung cancers. This conference and consensus documents aim to provide recommendations to assist in the evaluation of patients for SOT given a history of a pretransplant malignancy.
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Testimonio de Experto , Trasplante de Órganos , Consenso , Humanos , Recurrencia Local de Neoplasia , PronósticoRESUMEN
BACKGROUND: Single-center trials and retrospective case series have reported promising outcomes using kidneys from donors with hepatitis C virus (HCV) infection. However, multicenter trials are needed to determine if those findings are generalizable. METHODS: We conducted a prospective trial at seven centers to transplant 30 kidneys from deceased donors with HCV viremia into HCV-uninfected recipients, followed by 8 weeks of once-daily coformulated glecaprevir and pibrentasvir, targeted to start 3 days posttransplant. Key outcomes included sustained virologic response (undetectable HCV RNA 12 weeks after completing treatment with glecaprevir and pibrentasvir), adverse events, and allograft function. RESULTS: We screened 76 patients and enrolled 63 patients, of whom 30 underwent kidney transplantation from an HCV-viremic deceased donor (median kidney donor profile index, 53%) in May 2019 through October 2019. The median time between consent and transplantation of a kidney from an HCV-viremic donor was 6.3 weeks. All 30 recipients achieved a sustained virologic response. One recipient died of complications of sepsis 4 months after achieving a sustained virologic response. No severe adverse events in any patient were deemed likely related to HCV infection or treatment with glecaprevir and pibrentasvir. Three recipients developed acute cellular rejection, which was borderline in one case. Three recipients developed polyomavirus (BK) viremia near or >10,000 copies/ml that resolved after reduction of immunosuppression. All recipients had good allograft function, with a median creatinine of 1.2 mg/dl and median eGFR of 57 ml/min per 1.73 m2 at 6 months. CONCLUSIONS: Our multicenter trial demonstrated safety and efficacy of transplantation of 30 HCV-viremic kidneys into HCV-negative recipients, followed by early initiation of an 8-week regimen of glecaprevir and pibrentasvir.
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Ácidos Aminoisobutíricos/uso terapéutico , Antivirales/uso terapéutico , Bencimidazoles/uso terapéutico , Ciclopropanos/uso terapéutico , Hepacivirus , Hepatitis C/prevención & control , Trasplante de Riñón , Lactamas Macrocíclicas/uso terapéutico , Leucina/análogos & derivados , Prolina/análogos & derivados , Quinoxalinas/uso terapéutico , ARN Viral/sangre , Sulfonamidas/uso terapéutico , Adulto , Aloinjertos/fisiología , Aloinjertos/virología , Ácidos Aminoisobutíricos/efectos adversos , Antivirales/efectos adversos , Bencimidazoles/efectos adversos , Ciclopropanos/efectos adversos , Combinación de Medicamentos , Femenino , Tasa de Filtración Glomerular , Hepatitis C/sangre , Humanos , Riñón/fisiología , Lactamas Macrocíclicas/efectos adversos , Leucina/efectos adversos , Leucina/uso terapéutico , Masculino , Prolina/efectos adversos , Prolina/uso terapéutico , Estudios Prospectivos , Pirrolidinas , Quinoxalinas/efectos adversos , Sulfonamidas/efectos adversos , Respuesta Virológica SostenidaRESUMEN
Plasma cells (PCs) are the major source of pathogenic allo- and autoantibodies and have historically demonstrated resistance to therapeutic targeting. However, significant recent clinical progress has been made with the use of second-generation proteasome inhibitors (PIs). PIs provide efficient elimination of plasmablast-mediated humoral responses; however, long-lived bone marrow (BM) resident PCs (LLPCs) demonstrate therapeutic resistance, particularly to first-generation PIs. In addition, durability of antibody (Ab) reduction still requires improvement. More recent clinical trials have focused on conditions mediated by LLPCs and have included mechanistic studies of LLPCs from PI-treated patients. A recent clinical trial of carfilzomib (a second-generation irreversible PI) demonstrated improved efficacy in eliminating BM PCs and reducing anti-HLA Abs in chronically HLA-sensitized patients; however, Ab rebound was observed over several weeks to months following PI therapy. Importantly, recent murine studies have provided substantial insights into PC biology, thereby further enhancing our understanding of PC populations. It is now clear that BMPC populations, where LLPCs are thought to primarily reside, are heterogeneous and have distinct gene expression, metabolic, and survival signatures that enable identification and characterization of PC subsets. This review highlights recent advances in PC biology and clinical trials in transplant populations.
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Células Plasmáticas , Inhibidores de Proteasoma , Animales , Autoanticuerpos , Humanos , Ratones , Inhibidores de Proteasoma/uso terapéuticoRESUMEN
Simultaneous calcineurin inhibitor avoidance (CNIA) and early corticosteroid withdrawal (ESW) have not been achieved primarily due to excessive acute rejection. This trial compared 2 belatacept-based CNIA/ESW regimens with a tacrolimus-based ESW regimen. Kidney transplant recipients were randomized to receive alemtuzumab/belatacept, rabbit anti-thymocyte globulin (rATG)/belatacept, or rATG/tacrolimus. The combinatorial primary endpoint consisted of patient death, renal allograft loss, or a Modification of Diet in Renal Disease-calculated eGFR of <45 mL/min/1.73 m2 at 12 months. Results are reported by treatment group (alemtuzumab/belatacept, rATG/belatacept, and rATG/tacrolimus). Superiority was not observed at 1 year for the primary endpoint (9/107 [8.4%], 15/104 [14.4%], and 14/105 [13.3%], respectively; P = NS) for either belatacept-based regimen. Differences were not observed for secondary endpoints (death, death-censored graft loss, or estimated glomerular filtration rates < 45 mL/min/1.73 m2 ). Differences were observed in biopsy-proved acute cellular rejection (10.3%, 18.3%, and 1.9%, respectively) (P < .001), but not in antibody-mediated rejection, mixed acute rejection, or de novo donor-specific anti-HLA antibodies. Neurologic and electrolyte abnormality adverse events were less frequent under belatacept. Belatacept-based CNIA/ESW regimens did not prove to be superior for the primary or secondary endpoints. Belatacept-treated patients demonstrated an increase in biopsy-proved acute cellular rejection and reduced neurologic and metabolic adverse events. These results demonstrate that simultaneous CNIA/ESW is feasible without excessive acute rejection.
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Inhibidores de la Calcineurina , Trasplante de Riñón , Abatacept/uso terapéutico , Corticoesteroides/uso terapéutico , Rechazo de Injerto/tratamiento farmacológico , Rechazo de Injerto/etiología , Rechazo de Injerto/prevención & control , Supervivencia de Injerto , Humanos , Terapia de Inmunosupresión , Inmunosupresores/uso terapéutico , Estudios ProspectivosRESUMEN
Morbid obesity is a barrier to kidney transplant in patients with end-stage renal disease (ESRD). Laparoscopic sleeve gastrectomy (SG) is an increasingly considered intervention, but the safety and long-term outcomes are uncertain. We reviewed prospectively collected data on patients with ESRD and chronic kidney disease (CKD) undergoing SG from 2011 to 2018. There were 198 patients with ESRD and 45 patients with CKD (stages 1-4) who met National Institutes of Health guidelines for bariatric surgery and underwent SG; 72% and 48% achieved a body mass index of ≤ 40 and ≤ 35 kg/m2 , respectively. The mean percentages of total weight loss and excess weight loss were 18.9 ± 10.8% and 38.2 ± 20.3%, respectively. SG reduced hypertension (85.8% vs 52.1%), decreased antihypertensive medication use (1.6 vs 1.0) (P < .01 each), and reduced incidence of diabetes (59.6% vs 32.5%, P < .01). Of the 71 patients with ESRD who achieved a body mass index of ≤ 40 kg/m2 , 45 were waitlisted and received a kidney transplant, whereas 10 remain on the waitlist. Mortality rate after SG was 1.8 per 100 patient-years, compared with 7.3 for non-SG. Patients with stage 3a or 3b CKD exhibited improved glomerular filtration rate (43.5 vs 58.4 mL/min, P = .01). In conclusion, SG safely improves transplant candidacy while providing significant, sustainable effects on weight loss, reducing medical comorbidities, and possibly improving renal function in stage 3 patients.
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Gastrectomía , Fallo Renal Crónico/complicaciones , Obesidad Mórbida/cirugía , Adulto , Anciano , Femenino , Estudios de Seguimiento , Gastrectomía/métodos , Humanos , Fallo Renal Crónico/mortalidad , Fallo Renal Crónico/cirugía , Trasplante de Riñón , Masculino , Persona de Mediana Edad , Obesidad Mórbida/complicaciones , Obesidad Mórbida/mortalidad , Estudios Prospectivos , Tiempo de Tratamiento , Resultado del Tratamiento , Listas de Espera , Pérdida de PesoRESUMEN
Proteasome inhibitor-based strategies hold promise in transplant but have yielded varying results. Carfilzomib, a second-generation proteasome inhibitor, may possess advantages over bortezomib, the first-generation proteasome inhibitors. The purpose of this study was to evaluate the safety, toxicity, and preliminary efficacy of carfilzomib in highly HLA-sensitized kidney transplant candidates. Renal transplant candidates received escalating doses of carfilzomib followed by plasmapheresis (group A) or an identical regimen with additional plasmapheresis once weekly before carfilzomib dosing. Thirteen participants received carfilzomib, which was well tolerated with most adverse events classified as low grade. The safety profile was similar to bortezomib desensitization; however, neurotoxicity was not observed with carfilzomib. Toxicity resulted in permanent dose reduction in 1 participant but caused no withdrawals or deaths. HLA antibodies were substantially reduced with carfilzomib alone, and median maximal immunodominant antibody reduction was 72.8% (69.8% for group A, P = .031, 80.1% for group B, P = .938). After depletion, rebound occurred rapidly and antibody levels returned to baseline between days 81 and 141. Bone marrow studies revealed that approximately 69.2% of plasma cells were depleted after carfilzomib monotherapy. Carfilzomib monotherapy-based desensitization provides an acceptable safety and toxicity profile while leading to significant bone marrow plasma cell depletion and anti-HLA antibody reduction.
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Rechazo de Injerto/prevención & control , Terapia de Inmunosupresión/métodos , Inmunosupresores/administración & dosificación , Trasplante de Riñón , Oligopéptidos/administración & dosificación , Inhibidores de Proteasoma/administración & dosificación , Adolescente , Adulto , Anciano , Biomarcadores/sangre , Médula Ósea/inmunología , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Estudios de Seguimiento , Rechazo de Injerto/inmunología , Antígenos HLA/inmunología , Humanos , Inmunosupresores/uso terapéutico , Isoanticuerpos/sangre , Masculino , Persona de Mediana Edad , Oligopéptidos/uso terapéutico , Células Plasmáticas/inmunología , Estudios Prospectivos , Inhibidores de Proteasoma/uso terapéutico , Resultado del Tratamiento , Adulto JovenRESUMEN
Donor-specific antibodies (DSAs) have a deleterious effect on allografts and remain a major immunologic barrier in transplantation. Current therapies to eliminate DSAs are ineffective in highly HLA-sensitized patients. Proteasome inhibitors have been employed as a strategy to target bone marrow plasma cells (BMPCs), the source of long-term antibody production; however, their efficacy has been limited by poorly defined drug-resistance mechanisms. Here, we performed transcriptomic profiling of CD138+ BMPCs that survived in vivo desensitization therapy with the proteasome inhibitor carfilzomib to identify mechanisms of drug resistance. The results revealed a genomic signature that included increased expression of the immunoproteasome, a highly specialized proteasomal variant. Western blotting and functional studies demonstrated that catalytically active immunoproteasomes and the immunoproteasome activator PA28 were upregulated in carfilzomib-resistant BMPCs. Carfilzomib-resistant BMPCs displayed reduced sensitivity to the proteasome inhibitors carfilzomib, bortezomib, and ixazomib, but enhanced sensitivity to an immunoproteasome-specific inhibitor ONX-0914. Finally, in vitro carfilzomib treatment of BMPCs from HLA-sensitized patients increased levels of the immunoproteasome ß5i (PSMB8) catalytic subunit suggesting that carfilzomib therapy directly induces an adaptive immunoproteasome response. Taken together, our results indicate that carfilzomib induces structural changes in proteasomes and immunoproteasome formation.
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Médula Ósea/efectos de los fármacos , Resistencia a Medicamentos/genética , Oligopéptidos/farmacología , Células Plasmáticas/efectos de los fármacos , Complejo de la Endopetidasa Proteasomal/efectos de los fármacos , Inhibidores de Proteasoma/farmacología , Transcriptoma/efectos de los fármacos , Adaptación Fisiológica/efectos de los fármacos , Adaptación Fisiológica/inmunología , Biomarcadores/metabolismo , Western Blotting , Médula Ósea/inmunología , Humanos , Células Plasmáticas/inmunología , Complejo de la Endopetidasa Proteasomal/inmunología , Sindecano-1/metabolismo , Transcriptoma/inmunología , Investigación Biomédica Traslacional , Regulación hacia ArribaRESUMEN
RATIONALE & OBJECTIVE: Less than 4% of patients with kidney failure receive kidney transplants. Although discard rates of hepatitis C virus (HCV)-viremic kidneys are declining, ~39% of HCV-viremic kidneys donated between 2018 and 2019 were discarded. Highly effective antiviral agents are now available to treat chronic HCV infection. Thus, our objective was to examine the cost-effectiveness of transplanting kidneys from HCV-viremic donors into HCV-uninfected recipients. STUDY DESIGN: Markov state transition decision model. Data sources include Medline search results, bibliographies from relevant English language articles, Scientific Registry of Transplant Recipients, and the US Renal Data System. SETTING & POPULATION: US patients receiving maintenance hemodialysis who are on kidney transplant waiting lists. INTERVENTION(S): Transplantation with an HCV-unexposed kidney versus transplantation with an HCV-viremic kidney and HCV treatment. OUTCOMES: Effectiveness measured in quality-adjusted life-years and costs measured in 2018 US dollars. MODEL, PERSPECTIVE, AND TIMEFRAME: We used a health care system perspective with a lifelong time horizon. RESULTS: In the base-case analysis, transplantation with an HCV-viremic kidney was more effective and less costly than transplantation with an HCV-unexposed kidney because of the longer waiting times for HCV-unexposed kidneys, the substantial excess mortality risk while receiving dialysis, and the high efficacy of direct-acting antiviral agents for HCV infection. Transplantation with an HCV-viremic kidney was also preferred in sensitivity analyses of multiple model parameters. The strategy remained cost-effective unless waiting list time for an HCV-viremic kidney exceeded 3.1 years compared with the base-case value of 1.56 year. LIMITATIONS: Estimates of waiting times for patients willing to accept an HCV-viremic kidney were based on data for patients who received HCV-viremic kidney transplants. CONCLUSIONS: Transplanting kidneys from HCV-viremic donors into HCV-uninfected recipients increased quality-adjusted life expectancy and reduced costs compared with a strategy of transplanting kidneys from HCV-unexposed donors.
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Bencimidazoles/uso terapéutico , Fluorenos/uso terapéutico , Hepatitis C Crónica , Fallo Renal Crónico/cirugía , Trasplante de Riñón , Complicaciones Posoperatorias , Pirrolidinas/uso terapéutico , Quinoxalinas/uso terapéutico , Sulfonamidas/uso terapéutico , Uridina Monofosfato/análogos & derivados , Adulto , Antivirales/economía , Antivirales/uso terapéutico , Análisis Costo-Beneficio , Selección de Donante/economía , Selección de Donante/métodos , Combinación de Medicamentos , Femenino , Hepatitis C Crónica/diagnóstico , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C Crónica/etiología , Hepatitis C Crónica/virología , Humanos , Trasplante de Riñón/efectos adversos , Trasplante de Riñón/métodos , Masculino , Persona de Mediana Edad , Evaluación de Procesos y Resultados en Atención de Salud , Complicaciones Posoperatorias/tratamiento farmacológico , Complicaciones Posoperatorias/economía , Complicaciones Posoperatorias/virología , Sofosbuvir , Uridina Monofosfato/uso terapéutico , Viremia/diagnóstico , Viremia/etiologíaAsunto(s)
Virus BK , Trasplante de Riñón , Infecciones por Polyomavirus , Viremia , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Método Doble Ciego , Trasplante de Riñón/efectos adversos , Infecciones por Polyomavirus/complicaciones , Receptores de Trasplantes , Infecciones Tumorales por VirusRESUMEN
The purpose of this study was to determine the intrapatient (within the same patient) variability of tacrolimus in adherent patients. Daily tacrolimus trough levels were obtained at home using dried blood spot technology in kidney and liver transplant recipients. Patients were randomized to receive 3 formulations of tacrolimus, each for two 1-week periods. Adherence was monitored by patient diary, pill counts, and use of the Medication Event Monitoring System (MEMS). Variability was quantified as the coefficient of variation (CV). Comparison of CV between groups was by independent t test or one-way ANOVA as appropriate. The population was found to be adherent with a rate of 99.9% with a mean interval between the evening and morning dose of tacrolimus of 11.86 hours. The median CV for the entire population was 15.2% (range 4.8%-110%). There were no differences in CV by allograft type or tacrolimus formulation. The multivariate analysis did not identify any demographic characteristics associated with a CV > 30%. In a highly adherent population, tacrolimus did not display high intrapatient variability. Given the association between IPV and poor allograft outcomes, future studies are needed to quantitate the influence of adherence and establish target IPV goals.
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Rechazo de Injerto/tratamiento farmacológico , Supervivencia de Injerto/efectos de los fármacos , Trasplante de Riñón/métodos , Trasplante de Hígado/métodos , Complicaciones Posoperatorias , Tacrolimus/uso terapéutico , Receptores de Trasplantes/estadística & datos numéricos , Adulto , Femenino , Estudios de Seguimiento , Rechazo de Injerto/epidemiología , Humanos , Inmunosupresores/uso terapéutico , Incidencia , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Factores de Riesgo , Trasplante Homólogo , Estados Unidos/epidemiologíaRESUMEN
This report describes the results of 2 international randomized trials (total of 508 kidney transplant recipients). The primary objective was to assess the noninferiority of rabbit anti-thymocyte globulin (rATG, Thymoglobulin® ) versus interleukin-2 receptor antagonists (IL2RAs) for the quadruple endpoint (treatment failure defined as biopsy-proven acute rejection, graft loss, death, or loss to follow-up) to serve as the pivotal data for United States (US) regulatory approval of rATG. The pooled analysis provided an incidence of treatment failure of 25.1% in the rATG and 36.0% in the IL2RA treatment groups, an absolute difference of -10.9% (95% confidence interval [CI] -18.8% to -2.9%) supporting noninferiority (noninferiority margin was 10%) and superiority of rATG to IL2RA. In a meta-analysis of 7 trials comparing rATG with an IL2RA, the difference in the proportion of patients with BPAR at 12 months was -4.8% (95% CI -8.6% to -0.9%) in favor of rATG. In conclusion, a rigorous reanalysis of patient-level data from 2 prior randomized, controlled trials comparing rATG versus IL-2R monoclonal antibodies provided support for regulatory approval for rATG for induction therapy in renal transplant, making it the first T cell-depleting therapy approved for the prophylaxis of acute rejection in patients receiving a kidney transplant in the United States.