Three-month course of intragraft transcriptional changes in kidney allografts with early histological minimal injury - a cohort study.

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.

Revaluation and lessons learned from the first 9 cases of a Czech uterus transplantation trial: Four deceased donor and 5 living donor uterus transplantations.

Although uterus transplantation is still in the experimental stage, it has promising potential as a treatment for women with absolute uterine factor infertility based on the childbirths from living donor trials conducted in Sweden and the United States. We report the main characteristics and perioperative and postoperative courses of both recipients and donors following 4 deceased donor and 5 living donor uterus transplantations. Three main priorities differentiate this study from the previously reported uterus transplantations. First, clinical experience with the largest worldwide group of deceased donor uterine transplants is described. Second, in the majority of living donor uterine recipients, only 2 ovarian veins were used for venous blood outflow. All of these recipient procedures were surgically successful, and follow-up posttransplant ultrasound examinations revealed normal uterine blood supply and outflow. Third, in only one living and one deceased donor recipient, the transplanted uterus relied on only 2 uterine veins for venous outflow with a 50% surgical success rate. In all other recipients, 2 uterine and 2 ovarian veins were utilized. Although a successful pregnancy has not yet been achieved, the presented surgical and functional results of our trial are promising.

Isolated v-lesion represents a benign phenotype of vascular rejection of the kidney allograft - a retrospective study.

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.

Molecular diagnostics identifies risks for graft dysfunction despite borderline histologic changes.

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.

[Tubulointerstitial rejection of renal allografts]. / Tubulo-intersticiální rejekce stepu ledviny.

Tubulo-intersticial rejection represents T-cell mediated rejection of kidney allografts with the morphology of immune-mediated interstitial nephritis. Diagnosis is dependent on the histopathological evaluation of a graft biopsy sample. The key morphological features are interstitial inflammatory infiltrate and damage to tubular epithelial cell which in severe cases can result in the ruptures of the tubular basement membranes. The differential diagnosis of tubulo-interstitial rejection includes acute interstitial nephritis and viral inflammatory kidney diseases, mainly polyomavirus nephropathy.

Reproducibility of Rejection Grading in Uterus Transplantation: A Multicenter Study.

Background: Diagnosis of rejection after uterus transplantation is based on histopathological examination of ectocervical biopsies. Inflammation at the stromal-epithelial interface is the backbone of the histopathological classification proposed by our group in 2017. However, the reproducibility of this grading scheme has not been tested, and it is unclear whether it covers the full morphological spectrum of rejection. Methods: We present a multicenter study in which 5 pathologists from 4 uterus transplantation centers performed 2 rounds of grading on 145 and 48 cervical biopsies, respectively. Three of the centers provided biopsies. Additionally, the presence of perivascular stromal inflammation was recorded. During discussions after the first round, further histological lesions (venous endothelial inflammation and apoptosis) were identified for closer evaluation and added to the panel of lesions to score in the second round. All participants completed a questionnaire to explore current practices in handling and reporting uterus transplant biopsies. Results: Cervical biopsies were commonly performed in all centers to monitor rejection. Intraobserver reproducibility of rejection grading (performed by 1 rater) was excellent, whereas interobserver reproducibility was moderate and did not improve in the second round. Reproducibility of perivascular stromal inflammation was moderate but unsatisfactory for venous endothelial inflammation and apoptosis. All lesions were more frequent in, but not restricted to, biopsies with rejection patterns. Conclusions: Grading of rejection in cervical biopsies is reproducible and applicable to biopsies from different centers. Diagnosis of rejection may be improved by adding further histological lesions to the grading system; however, lesions require rigorous consensus definition.

Comparison of gene expression of epicardial and visceral adipocytes with regard to the differentiation stage.

BACKGROUND: Our study focused on the ability of epicardial adipocytes to produce bioactive substances and compare the extent of this production with the production of adipokines in visceral adipocytes, which are well known endocrine cells capable of contributing to the development of atherosclerosis. MATERIAL AND METHODS: The gene expression of human cytokines (IL-6, IL-8, IL-18, RANTES and MCP-1) and adipokines (leptin and adiponectin) was measured in primary cell lines of epicardial and visceral adipocytes, both in undifferentiated and mature statuses, after a 21-day-long differentiation protocol. Each condition was assayed in triplicate in two independent primary cell lines obtained from two different donors. RESULTS: The epicardial preadipocytes showed an increased expression of IL-8 (3.25-fold, p<0.05) compared with visceral preadipocytes. The expression of the atheroprotective adiponectin in epicardial preadipocytes was minimal compared with the expression in visceral preadipocytes (p<0.0001). Moreover, the expression of the genes of interest was dependent on the differentiation degree and cell origin. We observed an altered expression of the proinflammatory genes IL-8 (0.016-fold, p<0.01) and MCP-1 (0.19-fold, p<0.05) in differentiated epicardial adipocytes compared with undifferentiated adipocytes. The epicardial adipocytes showed an increased expression of IL-6 (8.13-fold, p<0.05) compared with the visceral adipocytes. CONCLUSION: Our results suggest that epicardial adipocytes substantially differ from visceral adipocytes and might locally contribute to the pathogenesis of coronary atherosclerosis.

[Caecal ligation and puncture in the minipig - a model of sepsis induction]. / Cékální ligace a punkce u miniprasat - metoda studia sepse.

BACKGROUND: Sepsis belongs among the most serious conditions and animal models of sepsis are the basic tools to investigate the pathophysiological response to this condition. MATERIAL AND METHODS: A total of 16 adult minipigs with identical baseline parameters were randomized into two groups. In the sepsis group (n = 10), sepsis was induced using caecal ligation and puncture (CLP). The control group (n = 6) underwent laparotomy without CLP. Selected clinical and laboratory parameters as well as histological findings between the sepsis and control group were subsequently compared. RESULTS: All animals undergoing CLP developed diffuse peritonitis and sepsis. Compared to the control group, experimental animals showed significant increase of body temperature and heart rate (while) requiring noradrenaline to maintain their perfusion pressure. No significant differences in the monitored biochemical parameters (including C-reactive protein levels) between the two groups were found. Histological findings in organs of experimental animals were consistent with changes of organs seen in sepsis, i.e., centrilobular liver necroses, acute tubular renal necrosis, serous fibrinopurulent exudate, myocardial malacias, and pulmonary edema. CONCLUSION: Experimental caecal ligation with a predefined size of the perforation in the intestinal wall is a suitable model for assessing the pathophysiological changes occurring in the body in sepsis.

Live Birth Following Uterine Transplantation From a Nulliparous Deceased Donor.

BACKGROUND: Nulliparous uterine grafts have never been used in uterus transplantation (UTx), possibly due to presumed infertility. Our objective was to verify the feasibility of nulliparous uterine graft transplantation. METHODS: The Czech Uterus Transplant Trial (registered under ClinicalTrials.gov, identifier NCT03277430) is a 2-arm trial comparing the efficacy of deceased donor (DD) versus live-donor uterus transplant (10 patients in both arms). A 25-year-old patient suffering from inborn absolute uterine factor infertility underwent a DD uterus transplant. The donor was a 20-year-old nulliparous brain-dead donor. RESULTS: The transplant procedure was uneventful. The posttransplant period was complicated by (1) recurrent episodes of acute cellular rejection, (2) neutropenia necessitating the administration of granulocyte colony-stimulating factor, (3) vaginal anastomotic stenosis treated with the insertion of a self-expanding stent, (4) the concurrence of Clostridium difficile colitis and acute appendicitis, and (5) temporary renal function impairment of a combined cause. Two years after the UTx, after the fourth embryo transfer, the patient became pregnant. Apart from gestational diabetes mellitus, the pregnancy was uneventful. Due to preterm contractions, delivery was achieved via caesarean section at gestational age 34 + 6 years. The postoperative course was uneventful for both the mother and the newborn. CONCLUSIONS: Herein, we report the first live birth after a DD UTx in Europe. This report provides a proof of concept that nulliparous uteri may present a suitable source of uterine grafts for UTx. Stenting may serve as a feasible treatment method for vaginal anastomotic stenosis.

Predictive Potential of Flow Cytometry Crossmatching in Deceased Donor Kidney Transplant Recipients Subjected to Peritransplant Desensitization.

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.

A novel double-endoloop technique for natural orifice transluminal endoscopic surgery gastric access site closure.

BACKGROUND: Effective and safe access site closure is critical for clinical application of natural orifice transluminal endoscopic surgery. OBJECTIVE: The current study evaluated a simple novel technique of gastrotomy closure. DESIGN: Feasibility study with a survival animal model. SETTING: Animal laboratory. SUBJECTS: Ten female domestic pigs. INTERVENTIONS: Endoscopic closure of a gastrotomy incision was evaluated in 10 pigs in a survival study. A standard double-channel endoscope was advanced into the peritoneal cavity through an incision made by a needle-knife and an 18-mm dilation balloon. After peritoneoscopy and salpingectomy, gastric closure was performed by using an endoscopic grasper and sequential application of 2 endoloops. After a follow-up period of 1 to 3 weeks, the pigs were killed for postmortem examination. MAIN OUTCOME MEASUREMENTS: Feasibility, efficiency, and safety of a novel closure technique. RESULTS: Correct positioning and delivery of endoloops was achieved in all animals in a median time of 17 minutes (range 13-25 minutes). All animals survived without complications. Postmortem examination demonstrated patent full-thickness gastric closure without any evidence of infection. LIMITATIONS: Feasibility study with a small number of subjects in a porcine model. CONCLUSION: Double endoloop technique represents a novel, simple, safe, and efficient means of gastric access site closure in natural orifice transluminal endoscopic surgery.

Confocal Laser Endomicroscopy vs Biopsies in the Assessment of Persistent or Recurrent Intestinal Metaplasia/Neoplasia after Endoscopic Treatment of Barrett's Esophagus related Neoplasia.

BACKGROUND AND AIMS: Patients after endoscopic treatment of Barrett's esophagus (BE) related neoplasia (BORN) should enter endoscopic surveillance with biopsies to detect persistent or recurrent neoplasia or intestinal metaplasia (IM). Probe-based confocal laser endomicroscopy (pCLE) serves as a virtual biopsy and could replace standard biopsies. However, the role of pCLE in patients after endoscopic treatment of BORN has not been systematically assessed. The aim of this study was to compare pCLE with biopsies in detecting persistent/recurrent IM/neoplasia. METHODS: A single center, prospective and pathologist-blinded study was performed. Patients after endoscopic treatment of BORN (endoscopic resection or dissection, radiofrequency ablation) underwent surveillance endoscopy with pCLE followed by biopsies. RESULTS: A total of 56 patients were enrolled: initial diagnoses were low-grade dysplasia (LGD) in 24 patients (43%), high-grade dysplasia (HGD) in 12 patients (21%) and early adenocarcinoma (EAC) in 20 patients (36%). Only one patient (2%) experienced recurrent neoplasia (LGD), which was diagnosed by pCLE only. Twenty patients (35.7%) experienced persistent/recurrent IM, diagnosed by both pCLE and biopsies in 17 patients (17/30, 85%) and by pCLE only in 3 pts (3/30, 15%). Sensitivity, specificity, positive and negative predictive values to diagnose recurrent/persistent IM did not differ significantly between pCLE and biopsies; diagnostic accuracy was 100% (95%CI 93.6-100) for pCLE and 94.6 (95%CI 85.1-98.9%) for biopsies, p=0.25. In patients with IM detected by both tested methods, pCLE detected significantly more goblet cells (median 43 per patient) than biopsies (median 12 per patient), p=0.01. CONCLUSION: pCLE is at least as effective as standard biopsies in the detection of persistent/recurrent IM after endoscopic treatment of BORN.

Probe-based confocal laser endomicroscopy versus biopsies in the diagnostics of oesophageal and gastric lesions: A prospective, pathologist-blinded study.

BACKGROUND AND AIM: Probe-based confocal laser endomicroscopy (pCLE) provides real-time microscopic visualisation. Our aim was to compare the diagnostic accuracy of pCLE with standard biopsies in patients with visible oesophageal or gastric lesions. METHODS: This was a single-centre, prospective, pathologist-blinded study. Patients underwent high-resolution endoscopy, and lesions were examined by pCLE followed by standard biopsies. A definitive diagnosis was determined from resection specimen. Main outcomes were overall diagnostic accuracy, sensitivity, specificity and positive and negative predictive values. RESULTS: We examined 74 lesions in 67 patients. Definitive diagnoses revealed 34 malignant and 40 non-malignant lesions. pCLE diagnosis was correct in 89.2% (66/74), while diagnosis based on biopsy was correct in 85% (57/67; p = 0.6). The overall diagnostic accuracy of biopsies was 85% (76-94%) and that of pCLE was 89% (79-96%). pCLE correctly diagnosed malignant lesions, comprising oesophageal adenocarcinoma, oesophageal squamous-cell cancer or gastric adenocarcinoma, in 88.2% (30/34) of cases, while biopsy was correctly diagnosed in 75.9% (22/29; p = 0.3). Sensitivity and specificity to diagnose a malignant lesion were 75.9% (95% confidence interval (CI) 56-89%) and 100% (95% CI 90-100%) for biopsies and 88.2% (95% CI 72-97%) and 92% (95% CI 79-98%) for pCLE. No differences between biopsies and pCLE were found with regard to sensitivity, specificity to diagnose dysplastic and benign lesions (p > 0.2). CONCLUSION: pCLE provides satisfactory diagnostic accuracy comparable with standard biopsies in patients with oesophageal or gastric lesions. ClinicalTrials.gov identifier: NCT0292049).

Molecular Fingerprints of Borderline Changes in Kidney Allografts Are Influenced by Donor Category.

The fate of transplanted kidneys is substantially influenced by graft quality, with transplantation of kidneys from elderly and expanded criteria donors (ECDs) associated with higher occurrence of delayed graft function, rejection, and inferior long-term outcomes. However, little is known about early molecular fingerprints of these events in different donor categories. Borderline changes represent the most frequent histological finding early after kidney transplantation. Therefore, we examined outcomes and transcriptomic profiles of early-case biopsies diagnosed as borderline changes in different donor categories. In this single-center, retrospective, observational study, we compared midterm outcomes of kidney transplant recipients with early borderline changes as a first pathology between ECD (n = 109), standard criteria donor (SCDs, n = 109), and living donor (LD, n = 51) cohorts. Intragraft gene expression profiling by microarray was performed in part of these ECD, SCD, and LD cohorts. Although 5 year graft survival in patients with borderline changes in early-case biopsies was not influenced by donor category (log-rank P = 0.293), impaired kidney graft function (estimated glomerular filtration rate by Chronic Kidney Disease Epidemiology Collaboration equation) at M3, 1, 2, and 3 years was observed in the ECD cohort (P < 0.001). Graft biopsies from ECD donors had higher vascular intimal fibrosis and arteriolar hyalinosis compared to SCD and LD (P < 0.001), suggesting chronic vascular changes. Increased transcripts typical for ECD, as compared to both LD and SCD, showed enrichment of the inflammatory, defense, and wounding responses and the ECM-receptor interaction pathway. Additionally, increased transcripts in ECD vs. LD showed activation of complement and coagulation and cytokine-cytokine receptor pathways along with platelet activation and cell cycle regulation. Comparative gene expression overlaps of ECD, SCD, and LD using Venn diagrams found 64 up- and 16 down-regulated genes in ECD compared to both LD and SCD. Shared increased transcripts in ECD vs. both SCD and LD included thrombospondin-2 (THBS2), angiopoietin-like 4 (ANGPTL4), collagens (COL6A3, COL1A1), chemokine CCL13, and interleukin IL11, and most significantly, down-regulated transcripts included proline-rich 35 (PRR35) and fibroblast growth factor 9. Early borderline changes in ECD kidney transplantation are characterized by increased regulation of inflammation, extracellular matrix remodeling, and acute kidney injury transcripts in comparison with both LD and SCD grafts.

Complete recovery of fulminant cytotoxic CD8 T-cell-mediated myocarditis after ECMELLA unloading and immunosuppression.

A 19-year-old woman with no previous cardiac history was admitted to the hospital with third-degree atrioventricular block and left ventricular dysfunction. Her condition quickly deteriorated to severe biventricular failure and cardiogenic shock requiring mechanical circulatory support. An endomyocardial biopsy revealed lymphocytic myocarditis with no PCR-detectable viral genomes, with CD8 T-cell predominance and pro-inflammatory macrophage expansion shown by myocardial flow cytometry. The therapy consisted of immunosuppression (high-dose methylprednisolone) and temporary mechanical circulatory support with enhanced ability to achieve left ventricular unloading by combination of extracorporeal membrane oxygenation with Impella (ECMELLA). After 2 weeks of support, complete and sustained recovery from myocarditis was observed.

Molecular patterns of isolated tubulitis differ from tubulitis with interstitial inflammation in early indication biopsies of kidney allografts.

The Banff 2019 kidney allograft pathology update excluded isolated tubulitis without interstitial inflammation (ISO-T) from the category of borderline (suspicious) for acute T cell-mediated rejection due to its proposed benign clinical outcome. In this study, we explored the molecular assessment of ISO-T. ISO-T or interstitial inflammation with tubulitis (I + T) was diagnosed in indication biopsies within the first 14 postoperative days. The molecular phenotype of ISO-T was compared to I + T either by using RNA sequencing (n = 16) or by Molecular Microscope Diagnostic System (MMDx, n = 51). RNA sequencing showed lower expression of genes related to interferon-y (p = 1.5 *10-16), cytokine signaling (p = 2.1 *10-20) and inflammatory response (p = 1.0*10-13) in the ISO-T group than in I + T group. Transcripts with increased expression in the I + T group overlapped significantly with previously described pathogenesis-based transcript sets associated with cytotoxic and effector T cell transcripts, and with T cell-mediated rejection (TCMR). MMDx classified 25/32 (78%) ISO-T biopsies and 12/19 (63%) I + T biopsies as no-rejection. ISO-T had significantly lower MMDx scores for interstitial inflammation (p = 0.014), tubulitis (p = 0.035) and TCMR (p = 0.016) compared to I + T. Fewer molecular signals of inflammation in isolated tubulitis suggest that this is also a benign phenotype on a molecular level.

Desminopathy: Novel Desmin Variants, a New Cardiac Phenotype, and Further Evidence for Secondary Mitochondrial Dysfunction.

Background: The pleomorphic clinical presentation makes the diagnosis of desminopathy difficult. We aimed to describe the prevalence, phenotypic expression, and mitochondrial function of individuals with putative disease-causing desmin (DES) variants identified in patients with an unexplained etiology of cardiomyopathy. Methods: A total of 327 Czech patients underwent whole exome sequencing and detailed phenotyping in probands harboring DES variants. Results: Rare, conserved, and possibly pathogenic DES variants were identified in six (1.8%) probands. Two DES variants previously classified as variants of uncertain significance (p.(K43E), p.(S57L)), one novel DES variant (p.(A210D)), and two known pathogenic DES variants (p.(R406W), p.(R454W)) were associated with characteristic desmin-immunoreactive aggregates in myocardial and/or skeletal biopsy samples. The individual with the novel DES variant p.(Q364H) had a decreased myocardial expression of desmin with absent desmin aggregates in myocardial/skeletal muscle biopsy and presented with familial left ventricular non-compaction cardiomyopathy (LVNC), a relatively novel phenotype associated with desminopathy. An assessment of the mitochondrial function in four probands heterozygous for a disease-causing DES variant confirmed a decreased metabolic capacity of mitochondrial respiratory chain complexes in myocardial/skeletal muscle specimens, which was in case of myocardial succinate respiration more profound than in other cardiomyopathies. Conclusions: The presence of desminopathy should also be considered in individuals with LVNC, and in the differential diagnosis of mitochondrial diseases.

Heterologous Cytomegalovirus and Allo-Reactivity by Shared T Cell Receptor Repertoire in Kidney Transplantation.

Cytomegalovirus (CMV) infection is associated with allograft rejection but the mechanisms behind are poorly defined yet. Although cross-reactivity of T cells to alloantigen and CMV has been hypothesized, direct evidence in patients is lacking. In this observational cohort study, we tested the pre-transplant effector/memory T cell response to CMV peptide pools and alloantigen in 78 living donor/recipient pairs using the interferon-gamma Enzyme-Linked ImmunoSpot (ELISPOT) assay. To prove the hypothesis of cross-reactivity, we analyzed by applying next-generation sequencing the T cell receptor ß (TCR- ß) repertoire of CMV- and alloantigen-reactive T cells enriched from peripheral pre-transplant blood of 11 CMV-seropositive and HLA class I mismatched patients. Moreover, the TCR-repertoire was also analyzed in the allograft biopsies of those patients. There was a significant association between the presence of pre-transplant CMV immediate-early protein 1 (IE-1)-specific effector/memory T cells and acute renal allograft rejection and function (p = 0.01). Most importantly, we revealed shared TCR-ß sequences between CMV-IE1 and donor alloantigen-reactive T cells in all pre-transplant peripheral blood samples analyzed in CMV-seropositive patients who received HLA class I mismatched grafts. Identical TCR sequences were also found in particular in post-transplant allograft biopsies of patients with concomitant CMV infection and rejection. Our data show the presence of functional, cross-reactive T cells and their clonotypes in peripheral blood and in kidney allograft tissue. It is therefore likely that CMV-donor cross-reactivity as well as CMV specific T cell elicited inflammation is involved in the processes that affect allograft outcomes.

Molecular Patterns Discriminate Accommodation and Subclinical Antibody-mediated Rejection in Kidney Transplantation.

BACKGROUND: Accommodation in ABO-incompatible (ABOi) transplantation and subclinical antibody-mediated rejection in HLA-incompatible (HLAi) transplantation share several morphological similarities. Because the clinical long-term outcomes differ, we hypothesized different molecular processes involved in ABOi transplantation and subclinical antibody-mediated rejection. METHODS: Using Illumina Human HT-12 v4 Expression BeadChips, the whole transcriptome was evaluated based on 3-month protocol C4d+ biopsies in otherwise stable ABOi and HLAi kidney grafts, as well as in C4d-negative HLA-compatible grafts exhibiting normal histological findings. Top differently regulated genes were further validated using real-time quantitative polymerase chain reaction in another patient cohort and complement regulatory proteins by immunohistochemistry. RESULTS: In the case of genes involved in immune response-related biological processes, ABOi and HLAi cohorts had similar transcriptomic profiles to C4d-negative controls. The majority of deregulated genes in the ABOi and HLAi groups consisted of metallothioneins and epithelial transporter genes. Increased expression of epithelial transporters (SLC4A1, SLC4A9, SLC17A3, SLC12A3, and SLC30A2) and class 1 metallothioneins (MT1F, MT1G, and MT1X) in HLAi transplantation was validated by real-time quantitative polymerase chain reaction. In comparison to controls, both incompatible cohorts were characterized by the upregulation of intrarenal complement regulatory genes. CD46 and CD59 transcripts were increased in the ABOi cohort, whereas CD46 solely in HLAi group, and CD59 protein expression was similar in both incompatible groups. CONCLUSIONS: Several epithelial transporters and metallothioneins discriminate subclinical antibody-mediated rejection in HLAi transplantation from accommodation in ABOi transplantation, which suggest different involved downstream mechanisms and increased risk of injury in HLAi settings. Metallothioneins with their antioxidative properties may help to attenuate the inflammation response induced by donor-specific anti-HLA antibody binding.

Simultaneous occurrence of autoimmune pancreatitis and pancreatic cancer in patients resected for focal pancreatic mass.

AIM: To assess the occurrence of autoimmune pancreatitis (AIP) in pancreatic resections performed for focal pancreatic enlargement. METHODS: We performed a retrospective analysis of medical records of all patients who underwent pancreatic resection for a focal pancreatic enlargement at our tertiary center from January 2000 to July 2013. The indication for surgery was suspicion of a tumor based on clinical presentation, imaging findings and laboratory evaluations. The diagnosis of AIP was based on histology findings. An experienced pathologist specialized in pancreatic disease reviewed all the cases and confirmed the diagnosis in pancreatic resection specimens suggestive of AIP. The histological diagnosis of AIP was set according to the international consensus diagnostic criteria. RESULTS: Two hundred ninety-five pancreatic resections were performed in 201 men and 94 women. AIP was diagnosed in 15 patients (5.1%, 12 men and 3 women) based on histology of the resected specimen. Six of them had AIP type 1, nine were diagnosed with AIP type 2. Pancreatic adenocarcinoma (PC) was also present in six patients with AIP (40%), all six were men. Patients with AIP + PC were significantly older (60.5 vs 49 years of age, P = 0.045), more likely to have been recently diagnosed with diabetes (67% vs 11%, P = 0.09), and had experienced greater weight loss (15.5 kg vs 8.5 kg, P = 0.03) than AIP patients without PC. AIP was not diagnosed in any patients prior to surgery; however, the diagnostic algorithm was not fully completed in every case. CONCLUSION: The possible co-occurrence of PC and AIP suggests that preoperative diagnosis of AIP does not rule out simultaneous presence of PC.