RESUMO
Most kidney transplant patients who undergo biopsies are classified as having no rejection based on consensus thresholds. However, we hypothesized that because these patients have normal adaptive immune systems, T cell-mediated rejection (TCMR) and antibody-mediated rejection (ABMR) may exist as subthreshold activity in some transplants currently classified as no rejection. To examine this question, we studied genome-wide microarray results from 5086 kidney transplant biopsies (4170 patients). An updated archetypal analysis designated 56% of biopsies as no rejection. Subthreshold molecular TCMR and/or ABMR activity molecular activity was detectable as elevated classifier scores in many biopsies classified as no rejection, with ABMR activity in many TCMR biopsies and TCMR activity in many ABMR biopsies. In biopsies classified as no rejection histologically and molecularly, molecular TCMR classifier scores correlated with increases in histologic TCMR features and molecular injury, lower eGFR, and higher risk of graft loss, and molecular ABMR activity correlated with increased glomerulitis and donor-specific antibody. No rejection biopsies with high subthreshold TCMR or ABMR activity had a higher probability of having TCMR or ABMR respectively diagnosed in a future biopsy. We conclude that many kidney transplant recipients have unrecognized subthreshold TCMR or ABMR activity, with significant implications for future problems.
RESUMO
BACKGROUND: Recurrence of immunoglobulin A nephropathy (IgAN) limits graft survival in kidney transplantation. However, predictors of a worse outcome are poorly understood. METHODS: Among 442 kidney transplant recipients (KTRs) with IgAN, 83 (18.8%) KTRs exhibited biopsy-proven IgAN recurrence between 1994 and 2020 and were enrolled in the derivation cohort. A multivariable Cox model predicting allograft loss based on clinical data at the biopsy and a web-based nomogram were developed. The nomogram was externally validated using an independent cohort (n = 67). RESULTS: Patient age <43 years {hazard ratio [HR] 2.20 [95% confidence interval (CI) 1.41-3.43], P < .001}, female gender [HR 1.72 (95% CI 1.07-2.76), P = .026] and retransplantation status [HR 1.98 (95% CI 1.13-3.36), P = .016] were identified as independent risk factors for IgAN recurrence. Patient age <43 years [HR 2.77 (95% CI 1.17-6.56), P = .02], proteinuria >1 g/24 hours [HR 3.12 (95% CI 1.40-6.91), P = .005] and C4d positivity [HR 2.93 (95% CI 1.26-6.83), P = .013] were found to be associated with graft loss in patients with IgAN recurrence. A nomogram predicting graft loss was constructed based on clinical and histological variables, with a C statistic of 0.736 for the derivation cohort and 0.807 for the external validation cohort. CONCLUSIONS: The established nomogram identified patients with recurrent IgAN at risk for premature graft loss with good predictive performance.
Assuntos
Glomerulonefrite por IGA , Humanos , Feminino , Adulto , Glomerulonefrite por IGA/complicações , Glomerulonefrite por IGA/cirurgia , Prognóstico , Nomogramas , Recidiva , Rim/patologia , Sobrevivência de Enxerto , Aloenxertos/patologia , Estudos RetrospectivosRESUMO
The ELISpot assay is a sensitive technique applied to assess cytokine-producing memory/effector T cells and human leukocyte antigens (HLA)-specific IgG-producing B cells. Besides the fact that the method is laborious and is difficult to standardise between laboratories, it may provide valuable information on the immune response of recipients before and after organ transplantation. In this article, we briefly review the recent literature and discuss the clinical significance of the ELISpot assay in predicting the risk and incidence of allograft rejection and survival.
Assuntos
Rejeição de Enxerto , Transplante de Rim , ELISPOT , Humanos , Interferon gama , Linfócitos TRESUMO
Personalizing immunosuppression is a major objective in transplantation. Transplant recipients are heterogeneous regarding their immunological memory and primary alloimmune susceptibility. This biomarker-guided trial investigated whether in low immunological-risk kidney transplants without pretransplant DSA and donor-specific T cells assessed by a standardized IFN-γ ELISPOT, low immunosuppression (LI) with tacrolimus monotherapy would be non-inferior regarding 6-month BPAR than tacrolimus-based standard of care (SOC). Due to low recruitment rates, the trial was terminated when 167 patients were enrolled. ELISPOT negatives (E-) were randomized to LI (n = 48) or SOC (n = 53), E+ received the same SOC. Six- and 12-month BPAR rates were higher among LI than SOC/E- (4/35 [13%] vs. 1/43 [2%], p = .15 and 12/48 [25%] vs. 6/53 [11.3%], p = .073, respectively). E+ patients showed similarly high BPAR rates than LI at 6 and 12 months (12/55 [22%] and 13/66 [20%], respectively). These differences were stronger in per-protocol analyses. Post-hoc analysis revealed that poor class-II eplet matching, especially DQ, discriminated E- patients, notably E-/LI, developing BPAR (4/28 [14%] low risk vs. 8/20 [40%] high risk, p = .043). Eplet mismatch also predicted anti-class-I (p = .05) and anti-DQ (p < .001) de novo DSA. Adverse events were similar, but E-/LI developed fewer viral infections, particularly polyoma-virus-associated nephropathy (p = .021). Preformed T cell alloreactivity and HLA eplet mismatch assessment may refine current baseline immune-risk stratification and guide immunosuppression decision-making in kidney transplantation.
Assuntos
Transplante de Rim , Tacrolimo , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto , Teste de Histocompatibilidade , Humanos , Terapia de Imunossupressão , Imunossupressores/uso terapêutico , Transplante de Rim/efeitos adversos , Linfócitos T , Tacrolimo/uso terapêuticoRESUMO
The tubulitis with/without interstitial inflammation not meeting criteria for T-cell-mediated rejection (minimal allograft injury) is the most frequent histological findings in early transplant biopsies. The course of transcriptional changes in sequential kidney graft biopsies has not been studied yet. Molecular phenotypes were analyzed using the Molecular Microscope® Diagnostic System (MMDx) in 46 indication biopsies (median 13 postoperative days) diagnosed as minimal allograft injury and in corresponding follow-up biopsies at 3 months. All 46 patients with minimal injury in early biopsy received steroid pulses. MMDx interpreted indication biopsies as no-rejection in 34/46 (74%), T-cell-mediated rejection (TCMR) in 4/46 (9%), antibody-mediated rejection in 6/46 (13%), and mixed rejection in 2/46 (4%) cases. Follow-up biopsies were interpreted by MMDx in 37/46 (80%) cases as no-rejection, in 4/46 (9%) as TCMR, and in 5/46 (11%) as mixed rejection. Follow-up biopsies showed a decrease in MMDx-assessed acute kidney injury (P = 0.001) and an increase of atrophy-fibrosis (P = 0.002). The most significant predictor of MMDx rejection scores in follow-up biopsies was the tubulitis classifier score in initial biopsies (AUC = 0.84, P = 0.002), confirmed in multivariate binary regression (OR = 16, P = 0.016). Molecular tubulitis score at initial biopsy has the potential to discriminate patients at risk for molecular rejection score at follow-up biopsy.
Assuntos
Rejeição de Enxerto , Transplante de Rim , Aloenxertos , Biópsia , Estudos de Coortes , Humanos , Rim , Transplante de Rim/efeitos adversosRESUMO
BACKGROUND: Preclinical studies suggested that pharmacological inhibition of the renin-angiotensin-aldosterone system (RAAS) by ACE inhibitors (ACEis) or angiotensin II receptor blockers (ARBs) may increase local angiotensin-converting enzyme 2 (ACE2) expression. METHODS: In this study, we evaluated the effect of ACEi or ARB treatment on expression of ACE2, ACE, and AGTR1 in 3-month protocol kidney allograft biopsies of stable patients using RT-qPCR (n = 48). Protein ACE2 expression was assessed using immunohistochemistry from paraffin sections. RESULTS: The therapy with RAAS blockers was not associated with increased ACE2, ACE, or ATGR1 expression in kidney allografts and also ACE2 protein immunohistochemistry did not reveal differences among groups. CONCLUSIONS: ACEis or ARBs in kidney transplant recipients do not affect local ACE2 expression. This observation supports long-term RAAS treatment in kidney transplant recipients, despite acute complications such as COVID-19 where ACE2 serves as the entry protein for infection.
Assuntos
Aloenxertos/efeitos dos fármacos , Antagonistas de Receptores de Angiotensina/uso terapêutico , Enzima de Conversão de Angiotensina 2/genética , Anti-Hipertensivos/uso terapêutico , Expressão Gênica/efeitos dos fármacos , Rim/efeitos dos fármacos , Adulto , Idoso , Aloenxertos/metabolismo , Antagonistas de Receptores de Angiotensina/farmacologia , Enzima de Conversão de Angiotensina 2/análise , Enzima de Conversão de Angiotensina 2/antagonistas & inibidores , Anti-Hipertensivos/farmacologia , COVID-19/complicações , COVID-19/genética , Feminino , Humanos , Rim/metabolismo , Transplante de Rim , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/análise , RNA Mensageiro/genética , Sistema Renina-Angiotensina/efeitos dos fármacosRESUMO
PURPOSE OF REVIEW: In this review, we discuss achievements in immunosuppression in kidney transplant recipients published at last 18 months. RECENT FINDINGS: Results of recent trials with everolimus in low-risk primary kidney transplant recipients suggest that lowTAC/EVR combination is noninferior and CMV and BKV viral infections are less frequent to standTAC/MPA. Iscalimab monoclonal antibody, which prevents CD40 to CD154 binding, has just recently entered phase II clinical studies in kidney transplantation. Eculizumab, anti-C5 monoclonal antobody was recently shown to improve outcomes in DSA+ living-donor kidney transplant recipients requiring pretransplant desensitization because of crossmatch positivity. Proximal complement C1 inhibition in patients with antibody-mediated rejection was studied in several phase I trials. SUMMARY: Recent knowledge creates a path towards future immunosuppression success in sensitized recipients and in those in high risk of viral infections or CNI nephrotoxicity.
Assuntos
Rejeição de Enxerto/prevenção & controle , Terapia de Imunossupressão/métodos , Imunossupressores/uso terapêutico , Transplante de Rim/métodos , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Everolimo/uso terapêutico , Rejeição de Enxerto/imunologia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Transplantados/estatística & dados numéricosRESUMO
Long-term peritoneal dialysis (PD) is associated with functional and structural alterations of the peritoneal membrane. Inflammation may be the key moment, and, consequently, fibrosis may be the end result of chronic inflammatory reaction. The objective of the present study was to identify genes involved in peritoneal alterations during PD by comparing the transcriptome of peritoneal cells in patients with short- and long-term PD. Peritoneal effluent of the long dwell of patients with stable PD was centrifuged to obtain peritoneal cells. The gene expression profiles of peritoneal cells using microarray between patients with short- and long-term PD were compared. Based on microarray analysis, 31 genes for quantitative RT-PCR validation were chosen. A 4-h peritoneal equilibration test was performed on the day after the long dwell. Transport parameters and protein appearance rates were assessed. Genes involved in the immune system process, immune response, cell activation, and leukocyte and lymphocyte activation were found to be substantially upregulated in the long-term group. Quantitative RT-PCR validation showed higher expression of CD24, lymphocyte antigen 9 (LY9), TNF factor receptor superfamily member 4 (TNFRSF4), Ig associated-α (CD79A), chemokine (C-C motif) receptor 7 (CCR7), carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1), and IL-2 receptor-α (IL2RA) in patients with long-term PD, with CD24 having the best discrimination ability between short- and long-term treatment. A relationship between CD24 expression and genes for collagen and matrix formation was shown. Activation of CD24 provoked by pseudohypoxia due to extremely high glucose concentrations in dialysis solutions might play the key role in the development of peritoneal membrane alterations.
Assuntos
Nefropatias/terapia , Diálise Peritoneal , Peritônio/metabolismo , Transcriptoma , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Regulação da Expressão Gênica , Humanos , Nefropatias/genética , Nefropatias/metabolismo , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND: The introduction of HLA matching of donors and recipients was a breakthrough in kidney transplantation. However, half of all transplanted kidneys still fail within 15 years after transplantation. Epidemiological data suggest a fundamental role of non-HLA alloimmunity. METHODS: We genotyped 477 pairs of deceased donors and first kidney transplant recipients with stable graft function at three months that were transplanted between Dec 1, 2005, and April 30, 2015. Genome-wide genetic mismatches in non-synonymous single nucleotide polymorphisms (nsSNPs) were calculated to identify incompatibilities in transmembrane and secreted proteins. We estimated the association between nsSNP mismatch and graft loss in a Cox proportional hazard model, adjusting for HLA mismatch and clinical covariates. Customised peptide arrays were generated to screen for antibodies against genotype-derived mismatched epitopes in 25 patients with biopsy-confirmed chronic antibody-mediated rejection. FINDINGS: 59â268 nsSNPs affecting a transmembrane or secreted protein were analysed. The median number of nsSNP mismatches in immune-accessible transmembrane and secreted proteins between donors and recipients was 1892 (IQR 1850-1936). The degree of nsSNP mismatch was independently associated with graft loss in a multivariable model adjusted for HLA eplet mismatch (HLA-A, HLA-B, HLA-C, HLA-DP, HLA-DQ, and HLA-DR). Each increase by a unit of one IQR had an HR of 1·68 (95% CI 1·17-2·41, p=0·005). 5-year death censored graft survival was 98% in the quartile with the lowest mismatch, 91% in the second quartile, 89% in the third quartile, and 82% in the highest quartile (p=0·003, log-rank test). Customised peptide arrays verified a donor-specific alloimmune response to genetically predicted mismatched epitopes. INTERPRETATION: Genetic mismatch of non-HLA haplotypes coding for transmembrane or secreted proteins is associated with an increased risk of functional graft loss independently of HLA incompatibility. As in HLA alloimmunity, donor-specific alloantibodies can be identified against genotype derived non-HLA epitopes. FUNDING: Austrian Science Fund, WWTF (Vienna Science and Technology Fund), and Ministry of Health of the Czech Republic.
Assuntos
Aloenxertos/imunologia , Rejeição de Enxerto/epidemiologia , Sobrevivência de Enxerto , Teste de Histocompatibilidade/estatística & dados numéricos , Transplante de Rim/estatística & dados numéricos , Adulto , Anticorpos/imunologia , Estudos de Casos e Controles , Feminino , Estudo de Associação Genômica Ampla , Rejeição de Enxerto/imunologia , Antígenos HLA/imunologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Polimorfismo de Nucleotídeo Único , Modelos de Riscos Proporcionais , Estudos Prospectivos , Doadores de TecidosRESUMO
PURPOSE OF REVIEW: This review summarises recent developments in monitoring and immunosuppressive management in kidney transplantation. RECENT FINDINGS: Long-term kidney allograft outcomes have not changed substantially mainly as a result of acute and chronic antibody-mediated rejection. Several groups have recently attempted to determine peripheral molecular fingerprints of ongoing rejection. But while this research is promising, it is not generalised for further spreading among different cohorts. Measurements of donor-derived cell-free DNA levels in recent studies have revealed better predictive values for antibody-mediated rejection. The Molecular Microscope Diagnostic System for assessing kidney graft biopsies has been gradually introduced within clinical practice, especially in complicated cases aimed at improving histological diagnostics. Molecular studies on accommodation in ABO-incompatible transplantation have shown increased complement regulation and lower expression of epithelial transporters and class 1 metallothioneins. Additionally, in clinical studies of sensitised patients, imlifidase has been shown to enable transplantation across significant immunological barriers, while the co-stimulation blockade has been tested to prevent donor specific antibodies development. In low-risk patients, everolimus/tacrolimus-based regimens have also proven their antiviral effects in large clinical trials. SUMMARY: Recent developments in non-invasive monitoring have paved the way for the introduction of future larger clinical trials with multiple patient cohorts.
Assuntos
Terapia de Imunossupressão/métodos , Transplante de Rim/métodos , HumanosRESUMO
Antibodies of non-human mammals are glycosylated with carbohydrate antigens, such as galactose-α-1-3-galactose (α-Gal) and N-glycolylneuraminic acid (Neu5Gc). These non-human carbohydrate antigens are highly immunogenic in humans due to loss-of-function mutations of the key genes involved in their synthesis. Such immunogenic carbohydrates are expressed on therapeutic polyclonal rabbit anti-human T-cell IgGs (anti-thymocyte globulin; ATG), the most popular induction treatment in allograft recipients. To decipher the quantitative and qualitative response against these antigens in immunosuppressed patients, particularly against Neu5Gc, which may induce endothelial inflammation in both the graft and the host. We report a prospective study of the antibody response against α-Gal and Neu5Gc-containing glycans following rabbit ATG induction compared to controls. We show a drop in the overall levels of anti-Neu5Gc antibodies at 6 and 12 months post-graft compared to the pre-existing levels due to the major early immunosuppression. However, in contrast, in a cross-sectional study there was a highly significant increase in anti-Neu5Gc IgGs levels at 6 months post-graft in the ATG-treated compared to non-treated patients(P = 0.007), with a clear hierarchy favouring anti-Neu5Gc over anti-Gal response. A sialoglycan microarray analysis revealed that the increased anti-Neu5Gc IgG response was still highly diverse against multiple different Neu5Gc-containing glycans. Furthermore, some of the ATG-treated patients developed a shift in their anti-Neu5Gc IgG repertoire compared with the baseline, recognizing different patterns of Neu5Gc-glycans. In contrast to Gal, Neu5Gc epitopes remain antigenic in severely immunosuppressed patients, who also develop an anti-Neu5Gc repertoire shift. The clinical implications of these observations are discussed.
Assuntos
Anticorpos/imunologia , Imunidade Celular/fisiologia , Imunoglobulina G/farmacologia , Fatores Imunológicos/farmacologia , Transplante de Rim/métodos , Ácidos Neuramínicos/imunologia , Adulto , Idoso , Anticorpos/metabolismo , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Timócitos/imunologia , Imunologia de Transplantes/fisiologia , Transplante HomólogoRESUMO
Intimal arteritis is known to be a negative prognostic factor for kidney allograft survival. Isolated v-lesion (IV) is defined as intimal arteritis with minimal tubulointerstitial inflammation (TI). Although the Banff classification assesses IV as T cell-mediated rejection (TCMR), clinical, and prognostic significance of early IV (early IV, eIV) with negative C4d and donor-specific antibodies (DSA) remains unclear. To help resolve if such eIV truly represents acute rejection, a molecular study was performed. The transcriptome of eIV (n=6), T cell-mediated vascular rejection with rich TI (T cell-mediated vascular rejection, TCMRV, n=4) and non-rejection histologic findings (n=8) was compared using microarrays. A total of 310 genes were identified to be deregulated in TCMRV compared with eIV. Gene enrichment analysis categorized deregulated genes to be associated primarily with T-cells associated biological processes involved in an innate and adaptive immune and inflammatory response. Comparison of deregulated gene lists between the study groups and controls showed only a 1.7% gene overlap. Unsupervised hierarchical cluster analysis revealed clear distinction of eIV from TCMRV and showed similarity with a control group. Up-regulation of immune response genes in TCMRV was validated using RT-qPCR in a different set of eIV (n=12) and TCMRV (n=8) samples. The transcriptome of early IV (< 1 month) with negative C4d and DSA is associated with a weak immune signature compared with TCMRV and shows similarity with normal findings. Such eIV may feature non-rejection origin and reflect an injury distinct from an alloimmune response. The present study supports use of molecular methods when interpreting kidney allograft biopsy findings.
Assuntos
Arterite/genética , Rejeição de Enxerto/genética , Transplante de Rim/métodos , Transcriptoma , Túnica Íntima/metabolismo , Adulto , Idoso , Aloenxertos , Estudos de Casos e Controles , Estudos Transversais , Feminino , Perfilação da Expressão Gênica/métodos , Ontologia Genética , Rejeição de Enxerto/diagnóstico , Humanos , Masculino , Estudos Retrospectivos , Túnica Íntima/patologiaRESUMO
BACKGROUND: Cytomegalovirus (CMV) prophylaxis may prevent CMV indirect effects in renal transplant recipients. This study aimed to compare the efficacy of valganciclovir and valacyclovir prophylaxis for CMV after renal transplantation with the focus on chronic histologic damage within the graft. METHODS: From November 2007 through April 2012, adult renal transplant recipients were randomized, in an open-label, single-center study, at a 1:1 ratio to 3-month prophylaxis with valganciclovir (n = 60) or valacyclovir (n = 59). The primary endpoint was moderate-to-severe interstitial fibrosis and tubular atrophy assessed by protocol biopsy at 3 years evaluated by a single pathologist blinded to the study group. The analysis was conducted in an intention-to-treat population. RESULTS: Among the 101 patients who had a protocol biopsy specimen available, the risk of moderate-to-severe interstitial fibrosis and tubular atrophy was significantly lower in those treated with valganciclovir (22% versus 34%; adjusted odds ratio, 0.31; 95% confidence interval, 0.11-0.90; P = 0.032 by multivariate logistic regression). The incidence of CMV disease (9% versus 2%; P = 0.115) and CMV DNAemia (36% versus 42%; P = 0.361) were not different at 3 years. CONCLUSIONS: Valganciclovir prophylaxis, as compared with valacyclovir, was associated with a reduced risk of moderate-to-severe interstitial fibrosis and tubular atrophy in patients after renal transplantation. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ( ACTRN12610000016033 ). Registered on September 26, 2007.
Assuntos
Infecções por Citomegalovirus/prevenção & controle , Citomegalovirus/efeitos dos fármacos , Sobrevivência de Enxerto/efeitos dos fármacos , Nefropatias/prevenção & controle , Transplante de Rim , Valaciclovir/uso terapêutico , Valganciclovir/uso terapêutico , Adulto , Antibioticoprofilaxia/métodos , Antivirais/uso terapêutico , Austrália/epidemiologia , Infecções por Citomegalovirus/epidemiologia , Relação Dose-Resposta a Droga , Feminino , Fibrose/epidemiologia , Fibrose/prevenção & controle , Humanos , Incidência , Análise de Intenção de Tratamento , Rim/efeitos dos fármacos , Rim/patologia , Nefropatias/epidemiologia , Transplante de Rim/efeitos adversos , Transplante de Rim/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Transplante Homólogo/efeitos adversosRESUMO
While the detrimental impact of the humoral acute vascular rejection (AVR) phenotype is recognized, the prognostic significance of isolated v-lesion (IV) remains unclear. In this retrospective single-centre study, AVR was found in 98 of 1015 patients (9.7%) who had undergone kidney transplantation in 2010-2014, with donor-specific antibodies (DSA) evaluated in all of them. The outcome of four AVR phenotypes was evaluated during median follow-up of 59 months; in 25 patients with IV, 18 with T-cell-mediated vascular rejection (TCMVR), 19 with antibody-mediated vascular rejection (AMVR) and 36 with suspected antibody-mediated rejection (sAMVR). AVR was diagnosed mainly by for-cause biopsy (81%) early after transplantation (median 19 POD) and appeared as mild-grade intimal arteritis. IV occurred in low-sensitized patients after the first transplantation (96%) in the absence of DSA. IV responded satisfactorily to treatment (88%), showed no persistence of rejection in surveillance biopsy, and had stable graft function, minimal proteinuria and excellent DCGS (96%). Contrary to that, Kaplan-Meier estimate of 3-year DCGS of AMVR was 66% (log-rank = 0.0004). Early IV represents a benign phenotype of AVR with a favourable outcome. This study prompts further research to evaluate the nature of IV before considering any change in the classification and management.
Assuntos
Rejeição de Enxerto/imunologia , Transplante de Rim/efeitos adversos , Rim/imunologia , Insuficiência Renal/cirurgia , Adulto , Anticorpos/imunologia , Biópsia , Feminino , Sobrevivência de Enxerto , Antígenos HLA/imunologia , Humanos , Imunossupressores , Estimativa de Kaplan-Meier , Rim/patologia , Masculino , Pessoa de Meia-Idade , Fenótipo , Estudos Retrospectivos , Risco , Linfócitos T/imunologia , Fatores de TempoRESUMO
Secondary hyperparathyroidism is a well-known complication of end-stage renal disease (ESRD). Both nodular and diffuse parathyroid hyperplasia occur in ESRD patients. However, their distinct molecular mechanisms remain poorly understood. Parathyroid tissue obtained from ESRD patients who had undergone parathyroidectomy was used for Illumina transcriptome screening and subsequently for discriminatory gene analysis, pathway mapping, and gene annotation enrichment analysis. Results were further validated using quantitative RT-PCR on the independent larger cohort. Microarray screening proved homogeneity of gene transcripts in hemodialysis patients compared with the transplant cohort and primary hyperparathyroidism; therefore, further experiments were performed in hemodialysis patients only. Enrichment analysis conducted on 485 differentially expressed genes between nodular and diffuse parathyroid hyperplasia revealed highly significant differences in Gene Ontology terms and the Kyoto Encyclopedia of Genes and Genomes database in ribosome structure (P = 3.70 × 10-18). Next, quantitative RT-PCR validation of the top differently expressed genes from microarray analysis proved higher expression of RAN guanine nucleotide release factor (RANGRF; P < 0.001), calcyclin-binding protein (CACYBP; P < 0.05), and exocyst complex component 8 (EXOC8; P < 0.05) and lower expression of peptidylprolyl cis/trans-isomerase and NIMA-interacting 1 (PIN1; P < 0.01) mRNA in nodular hyperplasia. Multivariate analysis revealed higher RANGRF and lower PIN1 expression along with parathyroid weight to be associated with nodular hyperplasia. In conclusion, our study suggests the RANGRF transcript, which controls RNA metabolism, to be likely involved in pathways associated with the switch to nodular parathyroid growth. This transcript, along with PIN1 transcript, which influences parathyroid hormone secretion, may represent new therapeutical targets to cure secondary hyperparathyroidism.
Assuntos
Hiperplasia Nodular Focal do Fígado/genética , Hiperplasia Nodular Focal do Fígado/terapia , Hiperparatireoidismo Secundário/genética , Hiperparatireoidismo Secundário/terapia , Diálise Renal , Adulto , Idoso , Feminino , Hiperplasia Nodular Focal do Fígado/etiologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/genética , Humanos , Hiperparatireoidismo Primário/patologia , Hiperparatireoidismo Secundário/etiologia , Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Família Multigênica/genética , Glândulas Paratireoides/patologia , Hormônio Paratireóideo/sangue , Paratireoidectomia , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Transcriptoma/genéticaRESUMO
B cells play an important role in the immune responses which affect the outcomes of kidney allografts. Dynamic changes of B-cell compartments in clinical kidney transplantation are still poorly understood. B-cell subsets were prospectively monitored using flow cytometry for 1 year in 98 kidney transplant recipients. Data were correlated with immunosuppression and clinical outcomes. An increase in the total population of B lymphocytes was observed during the first week after transplantation. The level of IgM(high) CD38(high) CD24(high) transitional B cells reduced significantly up until the third month, with partial repopulation in the first year. Lower numbers of transitional B cells in the third month were associated with higher risk of graft rejection. IgM(+) IgD(+) CD27(-) naive B cells did not change within follow-up. IgM(+) CD27(+) nonswitched memory B cells and IgM(-) CD27(+) switched memory B cells increased on post-operative day 7. IgM(-) CD38(high) CD27(high) plasmablasts showed similar kinetics during the first post-transplant year, similar to transitional B cells. In conclusion, sensitized kidney transplant recipients as well as those with either acute or chronic rejection within the first post-transplant year exhibited lower levels of transitional B cells. Therefore, these data further support the hypothesis that transitional B cells have a protective role in kidney transplantation.
Assuntos
Subpopulações de Linfócitos B/imunologia , Rejeição de Enxerto/imunologia , Memória Imunológica/imunologia , Transplante de Rim , Células Precursoras de Linfócitos B/imunologia , ADP-Ribosil Ciclase 1/metabolismo , Adolescente , Adulto , Idoso , Aloenxertos , Antígeno CD24/metabolismo , Criança , Pré-Escolar , Feminino , Humanos , Terapia de Imunossupressão , Masculino , Pessoa de Meia-Idade , Plasmócitos/imunologia , Estudos Prospectivos , Sensibilidade e Especificidade , Fatores de Tempo , Transplantados , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo , Adulto JovemRESUMO
The significance of borderline changes in kidney allograft biopsies is widely debated. To help resolve this, we studied differences in intrarenal gene expression patterns between early clinical and 3-month protocol biopsies, all of which had borderline histologic changes. The gene expression profiles in training set of patients by microarray analysis and data were validated in a larger cohort using RT-qPCR. There was greater expression of immunity- and inflammation-related genes in the early clinical biopsies compared to the 3-month protocol biopsies with borderline changes. In early clinically manifested borderline changes, graft deterioration within 24 months due to chronic rejection was associated with increased activation of immune, defense, and inflammatory processes. Regression modeling identified higher donor age and expression of macrophage receptor CLEC5A as risk factors for progression. In the 3-month protocol biopsies with borderline changes, graft dysfunction was associated with increased expression of fibrinogen complex transcripts. The discrimination power of fibrinogen was confirmed by cross-validation on two independent cohorts. Thus, our study highlights variations in gene expression between clinical and subclinical borderline changes despite similar histological findings. The data also support a recommendation for frequent patient monitoring, especially in those with borderline changes who received grafts from older donors.
Assuntos
Marcadores Genéticos , Rejeição de Enxerto/genética , Rejeição de Enxerto/patologia , Transplante de Rim/efeitos adversos , Rim/patologia , Técnicas de Diagnóstico Molecular , Adulto , Idoso , Doenças Assintomáticas , Biópsia , Diagnóstico Precoce , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Predisposição Genética para Doença , Rejeição de Enxerto/fisiopatologia , Humanos , Rim/fisiopatologia , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo , Reação em Cadeia da Polimerase , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do TratamentoRESUMO
BACKGROUND: Gene SLCO1B1, encoding solute organic anionic transport polypeptide OATP1B1, belongs to the group of candidates potentially influencing statin treatment safety. OATP1B1 regulates (not only) the hepatic uptake of statins. Its genetic variation was described as an important predictor of statin-associated myopathy in a cohort of patients treated with a maximum dose of simvastatin. However, the impact of SLCO1B1 gene polymorphism on this risk in patients treated with other statins or lower doses of simvastatin needs to be assessed. Therefore, we performed the present study. MATERIAL/METHODS: SLCO1B1 tagging rs4363657 polymorphism was analyzed in 2 groups of patients with dyslipidemia (treated with simvastatin or atorvastatin, 10 or 20 mg per day), subgroup with statin-induced myalgia (N=286), and subgroup (N=707) without myalgia/myopathy, and in 2301 population controls without lipid-lowering treatment. RESULTS: Frequency of the individual genotypes in patients with myalgia/myopathy (TT=62.3%, CT=34.5%, CC=2.8%) did not significantly differ (both P values over 0.19) from that in patients without muscle symptoms (TT=61.4%, CT=32.9%, CC=5.7%) or from the population controls (TT=63.9%, CT=32.5%, CC=3.6%). Null results were also obtained for the dominant and recessive models of the analysis. CONCLUSIONS: In Czech patients treated with low statin doses, there is no association between SLCO1B1 gene polymorphism and risk of myalgia/myopathy.
Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Doenças Musculares/induzido quimicamente , Transportadores de Ânions Orgânicos/genética , Polimorfismo de Nucleotídeo Único , Idoso , Atorvastatina/administração & dosagem , Atorvastatina/efeitos adversos , Atorvastatina/farmacocinética , Atorvastatina/uso terapêutico , República Tcheca/epidemiologia , Diabetes Mellitus/epidemiologia , Relação Dose-Resposta a Droga , Dislipidemias/tratamento farmacológico , Dislipidemias/genética , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Hepatócitos/metabolismo , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacocinética , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Transportador 1 de Ânion Orgânico Específico do Fígado , Masculino , Pessoa de Meia-Idade , Modelos Genéticos , Doenças Musculares/epidemiologia , Doenças Musculares/genética , Mialgia/induzido quimicamente , Mialgia/epidemiologia , Mialgia/genética , Obesidade/epidemiologia , Transportadores de Ânions Orgânicos/fisiologia , Sinvastatina/administração & dosagem , Sinvastatina/efeitos adversos , Sinvastatina/farmacocinética , Sinvastatina/uso terapêutico , Fumar/epidemiologiaRESUMO
BACKGROUND: Induction therapy can improve kidney transplantation (KTx) outcomes, but little is known about the mechanisms underlying its effects. METHODS: The mRNA levels of T cell-related genes associated with tolerance or rejection (CD247, GZMB, PRF1, FOXP3, MAN1A1, TCAIM, and TLR5) and lymphocyte subpopulations were monitored prospectively in the peripheral blood of 60 kidney transplant recipients before and 7, 14, 21, 28, 60, 90 days, 6 months, and 12 months after KTx. Patients were treated with calcineurin inhibitor-based triple immunosuppression and induction with rabbit anti-thymocyte globulin (rATG, n = 24), basiliximab (n = 17), or without induction (no-induction, n = 19). A generalized linear mixed model with gamma distribution for repeated measures, adjusted for rejection, recipient/donor age and delayed graft function, was used for statistical analysis. RESULTS: rATG treatment caused an intense reduction in all T cell type population and natural killer (NK) cells within 7 days, then a slow increase and repopulation was observed. This was also noticed in the expression levels of CD247, FOXP3, GZMB, and PRF1. The basiliximab group exhibited higher CD247, GZMB, FOXP3 and TCAIM mRNA levels and regulatory T cell (Treg) counts than the no-induction group. The levels of MAN1A1 and TLR5 mRNA expressions were increased, whereas TCAIM decreased in the rATG group as compared with those in the no-induction group. CONCLUSION: The rATG induction therapy was associated with decreased T and NK cell-related transcript levels and with upregulation of two rejection-associated transcripts (MAN1A1 and TLR5) shortly after KTx. Basiliximab treatment was associated with increased absolute number of Treg cells, and increased level of FOXP3 and TCAIM expression.
Assuntos
Expressão Gênica/efeitos dos fármacos , Rejeição de Enxerto/imunologia , Quimioterapia de Indução/métodos , Transplante de Rim/métodos , Adulto , Idoso , Anticorpos Monoclonais/uso terapêutico , Soro Antilinfocitário/uso terapêutico , Basiliximab , Complexo CD3/genética , Inibidores de Calcineurina/uso terapêutico , Feminino , Fatores de Transcrição Forkhead/genética , Rejeição de Enxerto/genética , Rejeição de Enxerto/prevenção & controle , Granzimas/genética , Humanos , Tolerância Imunológica/efeitos dos fármacos , Tolerância Imunológica/genética , Terapia de Imunossupressão/métodos , Imunossupressores/uso terapêutico , Contagem de Linfócitos , Masculino , Manosidases/genética , Pessoa de Meia-Idade , Células T Matadoras Naturais/efeitos dos fármacos , Células T Matadoras Naturais/imunologia , Perforina/genética , Estudos Prospectivos , RNA Mensageiro/sangue , Proteínas Recombinantes de Fusão/uso terapêutico , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Adulto JovemRESUMO
Introduction: Cardiovascular disease (CVD) is the leading cause of morbidity and mortality in kidney transplant recipient (KTR). There is a dearth of standardized guidelines on optimal cardiovascular evaluation of transplant candidates. Methods: This single-center cohort study aims to determine the effectiveness of our standardized risk-stratified pretransplant cardiovascular screening protocol, which includes coronary angiography (CAG), in identifying advanced CVD, the proper pretransplant management of which could lead to a reduction in the incidence of major cardiac events (MACE) in the early posttransplant period. Results: Out of the total 776 KTR transplanted between 2017 and 2019, CAG was performed on 541 patients (69.7%), of whom 22.4% were found to have obstructive coronary artery disease (CAD). Asymptomatic obstructive CAD was observed in 70.2% of cases. In 73.6% of cases, CAG findings resulted in myocardial revascularization. MACE occurred in 5.6% (N = 44) of the 23 KTR with pretransplant CVD and 21 without pretransplant CVD. KTR with posttransplant MACE occurrence had significantly worse kidney graft function at the first year posttransplant (p = 0.00048) and worse patient survival rates (p = 0.0063) during the 3-year follow-up period compared with KTR without MACE. After adjustment, the independent significant factors for MACE were arrhythmia (HR 2.511, p = 0.02, 95% CI 1.158-5.444), pretransplant history of acute myocardial infarction (HR 0.201, p = 0.046, 95% CI 0.042-0.970), and pretransplant myocardial revascularization (HR 0.225, p = 0.045, 95% CI 0.052-0.939). Conclusion: Asymptomatic CVD is largely prevalent in KTR. Posttransplant MACE has a negative effect on grafts and patient outcomes. Further research is needed to assess the benefits of pretransplant myocardial revascularization in asymptomatic kidney transplant candidates.