• Publikační typ
• úvodníky MeSH

• MeSH
• ABO systém krevních skupin MeSH
• cílené dárcovství tkání MeSH
• imunosupresivní léčba metody   MeSH
• internacionalita * MeSH
• isoprotilátky krev   MeSH
• lidé středního věku MeSH
• lidé MeSH
• přežívání štěpu MeSH
• senioři MeSH
• specificita protilátek MeSH
• studená ischemie MeSH
• testování histokompatibility MeSH
• transplantace ledvin metody   MeSH
• žijící dárci * MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• dopisy MeSH
• kazuistiky MeSH
• Geografické názvy
• Česká republika MeSH
• Rakousko MeSH

Recipient sensitization is a major risk factor of antibody-mediated rejection (ABMR) and inferior graft survival. The predictive effect of solid-phase human leukocyte antigen antibody testing and flow cytometry crossmatch (FCXM) in the era of peritransplant desensitization remains poorly understood. This observational retrospective single-center study with 108 donor-specific antibody (DSA)-positive deceased donor kidney allograft recipients who had undergone peritransplant desensitization aimed to analyze variables affecting graft outcome. ABMR rates were highest among patients with positive pretransplant FCXM vs. FCXM-negative (76 vs. 18.7%, p < 0.001) and with donor-specific antibody mean fluorescence intensity (DSA MFI) > 5,000 vs. <5,000 (54.5 vs. 28%, p = 0.01) despite desensitization. In univariable Cox regression, FCXM positivity, retransplantation, recipient gender, immunodominant DSA MFI, DSA number, and peak panel reactive antibodies were found to be associated with ABMR occurrence. In multivariable Cox regression adjusted for desensitization treatment (AUC = 0.810), only FCXM positivity (HR = 4.6, p = 0.001) and DSA number (HR = 1.47, p = 0.039) remained significant. In conclusion, our data suggest that pretransplant FCXM and DSA number, but not DSA MFI, are independent predictors of ABMR in patients who received peritransplant desensitization.

• Publikační typ
• časopisecké články MeSH

Background: Complement may contribute to donor-specific antibody (DSA)-triggered transplant injury. Here, we investigated whether the intrinsic strength of classical pathway and alternative pathway (AP) relates to the pathogenicity of DSA. Methods: Classical pathway and AP high-activity genotypes were defined according to C4 gene copy number and the presence of functional polymorphisms in C3 (C3102G), factor B (fB32R), and factor H (fH62V) genes. Associations of these genotypes with blood complement profiles and morphologic/molecular rejection features were evaluated in a cohort of 83 DSA-positive patients (antibody-mediated rejection [AMR], n = 47) identified upon cross-sectional screening of 741 kidney allograft recipients ≥180 days posttransplantation. Associations with long-term graft survival were evaluated in a larger kidney transplant cohort (n = 660) not enriched for a specific type of rejection. Results: In the cohort of DSA-positive subjects, the number of C4 gene copies was related to C4 protein levels in serum and capillary C4d staining, but not AMR activity. Patients with a high-activity AP complotype, which was associated with complement consumption in serum, showed enhanced microcirculation inflammation (median glomerulitis plus peritubular capillaritis score, 2 [interquartile range, 0-4 versus 1 0-2]; P = 0.037). In the larger transplant cohort, this complotype was associated with a slightly increased risk of graft loss (hazard ratio, 1.52; 95% confidence interval, 1.02-2.25; P = 0.038 and multivariable Cox model, 1.55; 1.04-2.32; P = 0.031). Conclusions: Our study suggests a contribution of complement genetics to the phenotypic presentation of AMR. Future studies will have to clarify whether a possible association of AP strength with graft survival relates to enhanced antibody-triggered injury.

• Publikační typ
• časopisecké články MeSH

Kidney paired donation (KPD) is a valuable tool to overcome immunological barriers in living donor transplantation. While small national registries encounter difficulties in finding compatible matches, multi-national KPD may be a useful strategy to facilitate transplantation. The Czech (Prague) and Austrian (Vienna) KPD programs, both initiated in 2011, were merged in 2015. A bi-national algorithm allowed for ABO- and low-level HLA antibody-incompatible exchanges, including the option of altruistic donor-initiated domino chains. Between 2011 and 2019, 222 recipients and their incompatible donors were registered. Of those, 95.7% (Prague) and 67.9% (Vienna) entered into KPD registries, and 81 patients received a transplant (95% 3-year graft survival). Inclusion of ABO-incompatible pairs in the Czech program contributed to higher KPD transplant rates (42.6% vs. 23.6% in Austria). After 2015 (11 bi-national match runs), the median pool size increased to 18 pairs, yielding 33 transplants (8 via cross-border exchanges). While matching rates doubled in Austria (from 9.1% to 18.8%), rates decreased in the Czech program, partly due to implementation of more stringent HLA antibody thresholds. Our results demonstrate the feasibility of merging small national KPD programs to increase pool sizes and may encourage the implementation of multi-national registries to expand the full potential of KPD.

• MeSH
• ledviny MeSH
• lidé MeSH
• retrospektivní studie MeSH
• transplantace ledvin * MeSH
• žijící dárci MeSH
• získávání tkání a orgánů * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika MeSH
• Rakousko MeSH

Background: In an earlier monocentric study, we have developed a novel non-invasive test system for the prediction of renal allograft rejection, based on the detection of a specific urine metabolite constellation. To further validate our results in a large real-world patient cohort, we designed a multicentric observational prospective study (PARASOL) including six independent European transplant centers. This article describes the study protocol and characteristics of recruited better patients as subjects. Methods: Within the PARASOL study, urine samples were taken from renal transplant recipients when kidney biopsies were performed. According to the Banff classification, urine samples were assigned to a case group (renal allograft rejection), a control group (normal renal histology), or an additional group (kidney damage other than rejection). Results: Between June 2017 and March 2020, 972 transplant recipients were included in the trial (1,230 urine samples and matched biopsies, respectively). Overall, 237 samples (19.3%) were assigned to the case group, 541 (44.0%) to the control group, and 452 (36.7%) samples to the additional group. About 65.9% were obtained from male patients, the mean age of transplant recipients participating in the study was 53.7 ± 13.8 years. The most frequently used immunosuppressive drugs were tacrolimus (92.8%), mycophenolate mofetil (88.0%), and steroids (79.3%). Antihypertensives and antidiabetics were used in 88.0 and 27.4% of the patients, respectively. Approximately 20.9% of patients showed the presence of circulating donor-specific anti-HLA IgG antibodies at time of biopsy. Most of the samples (51.1%) were collected within the first 6 months after transplantation, 48.0% were protocol biopsies, followed by event-driven (43.6%), and follow-up biopsies (8.5%). Over time the proportion of biopsies classified into the categories Banff 4 (T-cell-mediated rejection [TCMR]) and Banff 1 (normal tissue) decreased whereas Banff 2 (antibody-mediated rejection [ABMR]) and Banff 5I (mild interstitial fibrosis and tubular atrophy) increased to 84.2 and 74.5%, respectively, after 4 years post transplantation. Patients with rejection showed worse kidney function than patients without rejection. Conclusion: The clinical characteristics of subjects recruited indicate a patient cohort typical for routine renal transplantation all over Europe. A typical shift from T-cellular early rejections episodes to later antibody mediated allograft damage over time after renal transplantation further strengthens the usefulness of our cohort for the evaluation of novel biomarkers for allograft damage.

• Publikační typ
• časopisecké články MeSH

In several deceased donor kidney allocation systems, organs from elderly donors are allocated primarily to elderly recipients. The Eurotransplant Senior Program (ESP) was implemented in 1999, and since then, especially in Europe, the use of organs from elderly donors has steadily increased. The proportion of ≥60-year-old donors reported to the Collaborative Transplant Study (CTS) by European centers has doubled, from 21% in 2000-2001 to 42% in 2016-2017. Therefore, in the era of organ shortage it is a matter of debate whether kidney organs from elderly donors should only be allocated to elderly recipients or whether <65-year-old recipients can also benefit from these generally as "marginal" categorized organs. To discuss this issue, a European Consensus Meeting was organized by the CTS on April 12, 2018, in Heidelberg, in which 36 experts participated. Based on available evidence, it was unanimously concluded that kidney organs from 65- to 74-year-old donors can also be allocated to 55- to 64-year-old recipients, especially if these organs are from donors with no history of hypertension, no increased creatinine, no cerebrovascular death, and no other reasons for defining a marginal donor, such as diabetes or cancer.

• MeSH
• alografty MeSH
• dárci tkání MeSH
• ledviny MeSH
• lidé středního věku MeSH
• lidé MeSH
• přežívání štěpu MeSH
• senioři MeSH
• transplantace ledvin * MeSH
• věkové faktory MeSH
• získávání tkání a orgánů * MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• senioři MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Evropa MeSH

Highly sensitized (HS) patients in need of kidney transplantation (KTx) typically spend a longer time waiting for compatible kidneys, are unlikely to receive an organ offer, and are at increased risk of antibody-mediated rejection (AMR). Desensitization using imlifidase, which is more rapid and removes total body immunoglobulin G (IgG) to a greater extent than other methods, enables transplantation to occur between HLA-incompatible (HLAi) donor-recipient pairs and allows patients to have greater access to KTx. However, when the project was launched there was limited data and clinical experience with desensitization in general and with imlifidase specifically. Hence, this Delphi methodology was used to reach a consensus from a multi-disciplinary team (MDT) of experts from 15 countries on the management of HS patients undergoing imlifidase HLAi from a deceased donor (DD) KTx. This Delphi consensus provides clinical practice guidance on the use of imlifidase in the end-to-end management of HS patients undergoing an HLAi DD KTx and supports centers in the development of guidelines for the utilization and integration of imlifidase into clinical practice.

• MeSH
• dárci tkání * MeSH
• delfská metoda * MeSH
• desenzibilizace imunologická * metody   MeSH
• HLA antigeny * imunologie   MeSH
• imunoglobulin G MeSH
• konsensus * MeSH
• lidé MeSH
• rejekce štěpu prevence a kontrola   imunologie   MeSH
• transplantace ledvin * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND: Expression of acute kidney injury-associated (AKI-associated) transcripts in kidney transplants may reflect recent injury and accumulation of epithelial cells in "failed repair" states. We hypothesized that the phenomenon of failed repair could be associated with deterioration and failure in kidney transplants. METHODS: We defined injury-induced transcriptome states in 4,502 kidney transplant biopsies injury-induced gene sets and classifiers previously developed in transplants. RESULTS: In principal component analysis (PCA), PC1 correlated with both acute and chronic kidney injury and related inflammation and PC2 with time posttransplant. Positive PC3 was a dimension that correlated with epithelial remodeling pathways and anticorrelated with inflammation. Both PC1 and PC3 correlated with reduced survival, with PC1 effects strongly increasing over time whereas PC3 effects were independent of time. In this model, we studied the expression of 12 "new" gene sets annotated in single-nucleus RNA-sequencing studies of epithelial cells with failed repair in native kidneys. The new gene sets reflecting epithelial-mesenchymal transition correlated with injury PC1 and PC3, lower estimated glomerular filtration rate, higher donor age, and future failure as strongly as any gene sets previously derived in transplants and were independent of nephron segment of origin and graft rejection. CONCLUSION: These results suggest 2 dimensions in the kidney transplant response to injury: PC1, AKI-induced changes, failed repair, and inflammation; and PC3, a response involving epithelial remodeling without inflammation. Increasing kidney age amplifies PC1 and PC3. TRIAL REGISTRATION: INTERCOMEX (ClinicalTrials.gov NCT01299168); Trifecta-Kidney (ClinicalTrials.gov NCT04239703). FUNDING: Genome Canada; Natera, Inc.; and Thermo Fisher Scientific.

• MeSH
• akutní poškození ledvin * patologie   genetika   MeSH
• analýza hlavních komponent MeSH
• biopsie MeSH
• dospělí MeSH
• epitelo-mezenchymální tranzice genetika   MeSH
• epitelové buňky * patologie   metabolismus   MeSH
• ledviny patologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• průřezové studie MeSH
• rejekce štěpu * patologie   genetika   MeSH
• senioři MeSH
• transkriptom MeSH
• transplantace ledvin * škodlivé účinky   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• pozorovací studie MeSH

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 (from 4170 patients). An updated molecular 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 estimated glomerular filtration rate, 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.

• MeSH
• biopsie MeSH
• dospělí MeSH
• hodnoty glomerulární filtrace MeSH
• isoprotilátky imunologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• následné studie MeSH
• přežívání štěpu imunologie   MeSH
• prognóza MeSH
• rejekce štěpu * patologie   imunologie   etiologie   MeSH
• rizikové faktory MeSH
• T-lymfocyty imunologie   MeSH
• transplantace ledvin * škodlivé účinky   MeSH
• vyšetření funkce ledvin MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH