Graft Biopsy Specimens Research Articles

#4635 CIRCULATING NEPHRIN AUTOANTIBODIES IN PATIENTS WITH POST-TRANSPLANT RECURRENCE OF PRIMARY FOCAL SEGMENTAL GLOMERULOSCLEROSIS

Abstract Background and Aims Post-transplant recurrence of primary focal segmental glomerulosclerosis (FSGS) is a major challenge in the field of nephrology and kidney transplantation. Primary FSGS is thought to be caused by circulating factors (CFs) that injure podocytes, but these factors remain unknown despite intensive efforts to identify them. Recently, one post-transplant recurrent FSGS patient with pretransplant nephrin autoantibodies was reported (Watts AJB et al, JASN 33:238, 2022). Furthermore, we reported very early post-transplant recurrence changes of podocytes and possible roles of circulating nephrin autoantibodies in a patient with FSGS recurrence (Hattori M et al, AJT 22:2478, 2022). To confirm these preliminary results, we examined the autoantibodies to nephrin and the punctate deposition of IgG colocalized with nephrin using stocked plasma samples and grafted kidney biopsy specimens of the patients with FSGS recurrence. Method This study was approved by the local Ethics Committee of Tokyo Women's Medical University (approval no. 2021-0184). The clinical and research activities reported here are consistent with the Principles of the Declaration of Istanbul as outlined in the “Declaration of Istanbul on Organ Trafficking and Transplant Tourism”. From 1989 to 2022, a total of 78 patients with FSGS underwent kidney transplantation in our institution, and 16 patients experienced post-transplant recurrence of FSGS. Since the stoked plasma samples were available in 14 out of 16 patients, these 14 patients were included in this study. All 14 patients showed immediate post-transplant recurrence and had no pathogenic variants in FSGS-related genes including NPHS1. Circulating anti-nephrin autoantibodies were measured using the ELISA methods based on the Watts's report with one modification, that is, recombinant extracellular domain of human nephrin was obtained commercially (R&D systems, USA). To validate the ELISA system, circulating anti-nephrin autoantibodies were also measured in 9 genetic FSGS patients, 13 membranous nephropathy (MN) patients, 4 lupus nephritis (LN) patients, and 13 healthy controls. Dual immunofluorescence (IF) staining of nephrin and IgG and image acquisition using the two-dimensional structured illumination microscopy mode with a Nikon microscope were performed as previously reported (Hattori M et al, AJT 22:2478, 2022). Results The cut-off level of anti-nephrin antibody calculated from the results of a total 30 cases including 13 MN patients, 4 LN patients, and 13 healthy controls using Frey's formula (J Immunol Method, 1998) was 172.2 U/mL All 14 recurrent patients enrolled in this study had higher titter than the cut-off level and the mean ± SD of the anti-nephrin antibody level in these patients was 939.9 ± 261.8 U/mL. In contrast, the mean anti-nephrin antibody level in patients with genetic FSGS was 98.6 ± 77.3 U/mL, which was comparable with healthy controls. The IF staining of graft biopsy specimens showed punctate depositions of IgG colocalized with nephrin in all 14 recurrent patients. Conclusion The autoantibodies to nephrin in plasma samples and the punctate deposition of IgG colocalized with nephrin in grafted kidney biopsy specimens were observed in all 14 patients with post-transplant recurrent FSGS. Further studies in larger numbers of patients as well as in patients of other ethnicities are clearly required to confirm this surprising result; however, circulating nephrin autoantibodies could be a possible candidate for CFs in the pathogenesis of recurrent FSGS.

Assessment of Donor Liver Pathology Predicts Survival After Liver Transplantation: A Retrospective Cohort Study

The aims of this study were to investigate the pathologic manifestation of pretransplant biopsy and to provide an accurate assessment method for liver graft of China Donation after Citizen's Death (CDCD). A retrospective analysis was performed based on clinical and biopsy data of 96 CDCD liver transplantations completed between January 2012 and December 2017. The pretransplant pathologic sections were semiquantitatively scored according to Banff Schema recommendations on liver allograft pathology. Graft overall survival (OS) and early allograft dysfunction (EAD) rates were observed. The histologic analysis of the 96 CDCD liver graft biopsy specimens was summarized, including portal area neutrophilic infiltrate, macrovesicular steatosis, microvesicular steatosis, and hepatocellular swelling. Among these pathologic characteristics, only portal area neutrophilic infiltrate ≥20% was an independent risk factor for graft survival, although it has limited effect on the recipient's short-term prognosis. We found that portal area neutrophilic infiltrate ≥20% was an independent risk factors for long-term graft survival. According to this criterion, we can identify liver transplant recipients at risk for poor prognosis and make timely interventions.

Histologic Analysis of Porcine Dermal Graft Augmentation in Treatment of Rotator Cuff Tears

Background: Biologic augmentation via extracellular matrix (ECM) scaffolds has been utilized to address rotator cuff tears with poor-quality tissue. Purpose: To evaluate the cellular changes in graft explants taken from patients treated with porcine dermal grafts for rotator cuff tears. Study Design: Case series; Level of evidence, 4 Methods: Four graft biopsy specimens were obtained from patients treated with porcine dermal grafts in an interposition technique for rotator cuff tears and compared with a nonimplanted graft and a normal rotator cuff specimen. Biopsy of the graft site was performed at 18 days, 3 months, 7 months, and 10.5 months after implantation. Hematoxylin and eosin staining was used to evaluate for cellular and vascular changes. Picrosirius red (PSR) stain with 90° polarized light was performed to evaluate collagen fibril size and orientation. All biopsy specimens were analyzed by a pathologist. Results: There was evidence of progressive remodeling of the porcine dermal grafts. The most mature grafts demonstrated vessel infiltration and extensive remodeling without evidence of inflammation, foreign body reaction, or tissue rejection. PSR demonstrated increased organization of collagen domains, resembling normal tendon by 10.5 months postoperatively. Conclusion: This series suggests that ECM grafts may serve as an effective scaffold for host cell infiltration, collagen reorganization, and vascularization as a result of histologic changes demonstrated with retrieval of specimens from patients with rotator cuff tears that were augmented with porcine dermal grafts.

Shear Wave Elastography Performance in Noninvasive Assessment of Liver Cirrhosis in Liver Transplant Recipients With the Recurrence of Hepatitis C Infection

BackgroundThe recurrence of hepatitis C (HCV) after liver transplant (LTX) leads to graft fibrosis and cirrhosis. Liver biopsy remains the criterion standard for their diagnosis and monitoring. Our objective was evaluation of shear wave elastography (SWE) in patients with HCV recurrence after LTX and its comparison with histopathologic fibrosis assessment scoring systems. MethodsA total of 101 LTX recipients with HCV recurrence (42 women [41.6%] and 59 men [58.4%]) were evaluated by graft biopsy specimens (Ishak, Scheurer, and meta-analysis of histologic data in viral hepatitis [Metavir] score) and SWE (liver stiffness). Median age of patients was 59.4 years; median time from LTX was 84.9 months. The study protocol conforms with the Declaration of Helsinki. ResultsMedian liver stiffness was 21.3 kPa. To differentiate between liver fibrosis and cirrhosis, patients were divided into 2 subgroups: Ishak score fibrosis (1-4 [85.2%]) and cirrhosis (5-6 [13.9%]); Scheurer score fibrosis (0-3 [85.2%]) and cirrhosis (4 [12.9%]); Metavir score fibrosis (0-3 [85.2%]) and cirrhosis (4 [14.9%]). We have observed statistically significant differences between liver fibrosis and liver cirrhosis groups defined on the basis of Ishak, Scheurer, and Metavir scoring systems: 20.8 kPa vs 29.6 kPa (P = .001), 20.7 kPa vs 30.3 kPa (P = .0005), and 20.7 kPa vs 28.8 kPa (P = .002), respectively. ConclusionsOur results indicate that SWE may be useful in differentiating patients with advanced cirrhosis from those with fibrosis and may be helpful in the noninvasive diagnosis and monitoring of HCV recurrence after LTX.

Predictors of Acute Kidney Injury in Deceased Kidney Donors After Brain Death

BackgroundDonors with acute kidney injury (AKI) are generally accepted as a valuable source of kidneys for transplant. The aim of this study was to assess the risk of developing AKI based on deceased kidney donor parameters. Materials and MethodsThe data of 162 kidneys procured from deceased donors after brain death were collected. These included clinical characteristics of donors and histologic assessment in organ biopsy specimens. The donors’ kidney terminal function was classified according to the Acute Kidney Injury Network criteria. All biopsies were performed with the use of a 16G automatic needle, and the 20-mm tissue specimen was available in all cases. Biopsy specimens were secured and prepared in a routine way with hematoxylin and eosin. The presence of chronic changes was analyzed according to the Banff 2009 classification by 1 experienced nephropathologist. The logistic regression model was used to assess the risk of AKI regarding donor characteristics and histologic findings. ResultsThere were 50 kidneys (30.9%) with AKI identified. The risk of AKI increased with donor age (P = .002; odds ratio [OR], 1.02; 95% CI, 1.01–1.03), body mass index (P = .003; OR, 1.05; 95% CI, 1.01–1.09), and male sex (P = .001; OR, 1.79; 95% CI, 1.31–2.27). Regarding the histologic findings, the interstitial fibrosis presence was a risk factor of AKI (P = .004; OR, 1.04; 95% CI, 1.01–1.06). ConclusionsOlder donor age, male sex, higher body mass index, and presence of interstitial fibrosis in kidney graft biopsy specimen are risk factors of AKI.

Morphofunctional evaluation of liver grafts obtained from standard donors and expanded criteria donors

Donor organ shortage stimulated an active use of donors with expanded evaluation criteria. The main evaluation method was a histological examination of liver graft biopsy specimens before (time-zero biopsy) and after reperfusion (time-1 biopsy). Severe ischemic and reperfusion injuries among recipients who received a liver graft made 20.4% and 16.6% respectively. The study showed no impact of small droplet, medium droplet, or even large droplet steatosis (less than 50%) on graft reperfusion injury.

Predominant but silent C1q deposits in mesangium on transplanted kidneys - long-term observational study

BackgroundC1q nephropathy (C1qN) was first described as glomerular disease characterized by predominant meangial C1q deposits in patients with proteinuria and no evidence of systemic lupus erythematosus. Several studies, however, revealed the clinical heterogeneity of C1qN, showing some cases with normal urinalysis. To confirm the existence of cases with predominant mesangial C1q deposits and negative or mild proteinuria and/or hematuria, we investigated renal graft biopsy specimens showing negative to mild proteinuria (less than or equal to 1+ by dip stick test) and/or hematuria.MethodsEligible participants were kidney transplant cases who corresponded to the criteria for C1qN and were followed more than 10 years. Their medical records were reviewed to determine the age at detection of predominant mesangial C1q deposits, gender, original renal disease and reason for renal graft biopsy, blood pressure, degree of proteinuria and hematuria, and serum creatinine levels.ResultsFrom 414 cases in adults and children, five pediatric patients (the male to female ratio, 1:1.5) were eligible. At the time when predominant mesangial C1q deposits were detected, 2 cases presented with mild proteinuria without hematuria, but the other 3 cases showed normal urinalysis. Light microscopy revealed minor glomerular abnormality in all the cases. Immunofluorescent study showed predominant mesangial C1q deposits with IgG, IgM and C3 in all cases. All selected specimens presented electron dense-depos in the mesangium. Ten years later from the detection, 2 cases continued to be normal urinalysis and 3 cases had mild proteinuria without hematuria. During this follow-up period, no cases presented with persistent proteinuria and/or hematuria greater than or equal to 2+ by dip stick test. And no cases developed systemic lupus erythematosus. Follow-up renal graft biopsies were performed once in 2 cases 8 years later from the detection. They showed minor glomerular abnormalities. C1q deposit disappeared in one case. In another case, immunofluorescent study was not examined.ConclusionsThis long-term observational study on transplanted kidneys confirms the existence of cases with predominant but silent C1q deposits in the mesangium who have negative or mild proteinuria.

Abnormalities in Protocol Graft Kidney Biopsy 6 Months Posttransplantation in a Tertiary Care Center Hospital of Nepal

BackgroundIncreasing graft survival is the prime focus of every transplantation program. Detection of subclinical abnormalities with the help of protocol renal graft biopsies performed at predetermined intervals after transplantation has been one of the approaches.The objective was to study the abnormalities in protocol renal graft biopsy specimens at 6 months posttransplantation. MethodsThis was a hospital-based observational descriptive study. It included the recipients who underwent kidney transplantation between October 2014 and September 2015. The recipients were followed up postoperatively on an outpatient basis, as per the institution protocol. At 6 months posttransplantation, protocol graft biopsy was performed in all patients with normal functioning allograft without proteinuria after obtaining informed written consent. ResultsA total of 57 patients with chronic kidney disease underwent renal transplantation during the study period. Protocol biopsy was performed in 47 recipients.Subclinical rejection was found in 4 (8.5%) recipients. Two recipients had significant tubulitis and interstitial inflammation. One of them showed features of Banff Type IA cellular rejection (t2, i2) and another showed Banff Type IB cellular rejection (t3, i2). Biopsy specimen of 1 recipient showed significant glomerulitis and peritubular capillaritis (g3, ptc1). Another recipient showed significant peritubular capillaritis (ptc2) with C4d positivity. IgA nephropathy was present in 6 (12.8%) recipients. BK virus nephropathy was found in 2 (4.3%) recipients. ConclusionThis study demonstrates that abnormal histologic findings occur in protocol graft biopsy specimens at 6 months post renal transplantation in patients without any clinical or laboratory abnormalities.

Thin Glomerular Basement Membrane in a Kidney Transplant of an Alport's Syndrome Patient: A Case Report

Alport syndrome (AS) and thin basement membrane lesions are caused by various mutations in type IV collagen genes. Although AS is considered a rare disease, thin basement membrane is a frequent pattern, especially in families with a history of persistent hematuria. We report a patient with a diagnosis of AS who developed end-stage kidney disease (ESKD) and received a kidney transplant from a living unrelated donor. The graft biopsy specimen surprisingly showed a pattern of thin basement membranes.

Utility of Oxford Classification in Post-Transplant Immunoglobulin A Nephropathy

BackgroundWith increasing graft survival, post-transplant immunoglobulin A nephropathy (IgAN) has emerged as an important cause of chronic graft dysfunction in renal allograft recipients. We studied the clinico-pathological features of post-transplant IgAN regardless of the primary disease. The aim was to study the usefulness of the Oxford classification in predicting survival. MethodsIndication graft biopsy specimens (n = 915) were received during a 10-year period; 27 biopsy specimens from 22 patients were diagnosed as IgAN. ResultsPost-transplant IgAN was seen in 2.6% of biopsy specimens. Mean time to occurrence was 71.6 ± 47.6 months (range, 6.8 months to 16 years), occurring most commonly 4 to 8 years after transplant. Associated rejection was present in 4 biopsies; 72.7% (16/22), 91% (20/22), and 31.8% (7/22) presented with rise in serum creatinine, proteinuria, and hematuria, respectively. Four (21%) patients had nephrotic range proteinuria. Mesangial hypercelullarity (M1), endocapillary hypercelullarity (E1), segmental glomerulosclerosis (S1), and tubulo-interstitial fibrosis (T1-2) was present in 36.6%, 22.7%, 54.5%, and 31.8% biopsies, respectively. The most frequent Haas class was III (n = 7; 29.1%), followed by classes IV and I (n = 5; 20.8% each). The 2- and 5-year graft survival rates were 75% and 56%, respectively. High serum creatinine, low estimated glomerular filtration rate, E1 and T lesions, and degree of interstitial inflammation predicted graft survival. Interestingly, percentage (>25%) of segmentally sclerosed glomeruli and not S1 correlated with graft outcome. ConclusionsThe Oxford MEST scheme is useful in predicting graft survival in post-transplant IgAN. The degree of interstitial inflammation is also an important feature for determining graft outcomes in post-transplant IgAN.

Expression profile of mammalian target of rapamycin-related proteins in graft biopsy specimens: Significance for predicting interstitial fibrosis after kidney transplantation.

To investigate the influence of the expression profile of mammalian target of rapamycin-related proteins on the development of interstitial fibrosis after kidney transplantation. Immunohistochemical staining was carried out to evaluate the expression of five mammalian target of rapamycin-related proteins (phosphorylated-Akt, Ras homolog enriched in brain, phosphorylated-mammalian target of rapamycin, phosphorylated-p70 ribosomalS6 kinase and phosphorylated-4E binding protein1) in graft biopsy specimens obtained from 77 patients at 3months after kidney transplantation. The change of the estimated glomerular filtration rate and the change of the fibrosis index (defined as the change in the percent area of fibrosis on Masson's trichrome-stained sections of biopsy specimens) from 3months to 3years after kidney transplantation were determined. There was a significant correlation between change of the estimated glomerular filtration and change of the fibrosis index in the 77 patients. Univariate analysis identified expression of phosphorylated-Akt, phosphorylated-mammalian target of rapamycin and phosphorylated-p70 ribosomalS6 kinase, as well as donor type and pre-transplant dialysis duration, as significant predictors of a change of the fibrosis index >10%. However, only phosphorylated-mammalian target of rapamycin expression, phosphorylated-p70 ribosomalS6 kinase expression and donor type were independently associated with a change of the fibrosis index >10% according to multivariate analysis. These findings suggest that mammalian target of rapamycin-related proteins are involved in the development of interstitial fibrosis after kidney transplantation.

In Vivo Tissue Engineering of Human Airways

Airway transplantation remains a major challenge in thoracic surgery. Based on our previous laboratory work, we developed the techniques required to bioengineer a tracheal substitute invivo using cryopreserved aortic allografts as biological matrices (Replacement of the Airways and/or the Pulmonary Vessels Using a Cryopreserved Arterial Allograft [TRACHEOBRONCART] Study, NCT01331863). We present here 2 patients who had a definitive tracheostomy for complex laryngotracheal stenoses refractory to conventional therapy. According to our protocol, a stented gender-mismatched -80°C cryopreserved aortic allograft was used for airway reconstruction. Follow-up assessments were done at regular intervals using clinical, imaging, and endoscopic evaluations. Immunohistochemical and XX/XY chimerism studies were performed at time of stent removal using graft biopsy specimens. Chemotactic and angiogenic properties of implanted matrices were also investigated. At a maximal follow-up of 5 years and 7 months, the patients were breathing and speaking normally, without tracheostomy or stent. Regeneration of cartilage within the aortic grafts was demonstrated by positive immunodetection of type II collagen and markers specific for Sox9. Chimerism study from samples of neotissues demonstrated that regenerated cartilage came from recipient cells. The remaining viable matrix cells released a functionally relevant amount of proangiogenic, chemoattractant, proinflammatory/immunomodulatory cytokines, and growth factors. This report documents the feasibility of invivo tissue engineering for long-term functional airway transplantation in humans.

Hyperuricemia and Acute Renal Failure in Renal Transplant Recipients Treated With High-Dose Mizoribine

BackgroundHyperuricemia is a common adverse event frequently found in renal transplant recipients with mizoribine (MZ). Hyperuricemia itself will be a cause of renal dysfunction, and renal dysfunction also will be a cause of hyperuricemia simultaneously. This study investigates frequency of hyperuricemia and renal failure in renal transplant recipients treated with high-dose MZ. Patients and MethodsFrom December 2007 to October 2015, there was a total of 32 living related renal transplant recipients treated with high-dose MZ. Of the 32 patients, 28 were treated with urate-lowering medications. ResultsOne patient received allopurinol (AP) and 13 patients received benzbromarone (BB). For 6 of them, their urate-lowering medications were converted to febuxostat (FX) form AP or BB. In the remaining 14 patients, FX was administered from the beginning. In 2 cases of ABO-incompatible living related renal transplant recipients who were maintained with high-dose MZ and BB, severe hyperuricemia and acute renal failure occurred. One patient was a 48-year-old man, and his creatinine (Cr) level increased to 8.14 mg/dL and his serum uric acid (UA) was 24.6 mg/dL. Another patient was a 57-year-old man, and his Cr level increased to 3.59 mg/dL and his UA was 13.2 mg/dL. In both cases Cr and UA were improved, and no finding of acute rejection and drug toxicity was observed in graft biopsy specimens. BB was switched to FX and discontinuance or reduction of MZ was done. ConclusionCombination of MZ and BB has the risk of acute renal dysfunction after renal transplantation. Latent renal dysfunction should be watched for in renal transplant recipients receiving high-dose MZ.

Hypoxia-Inducible Factor-1α Expression in Kidney Transplant Biopsy Specimens After Reperfusion Is Associated With Early Recovery of Graft Function After Cadaveric Kidney Transplantation

BackgroundIschemia/reperfusion injury during kidney transplantation (KTx) delays allograft recovery. Hypoxia-inducible factor-1α (HIF-1α) is the key regulator of the protective response to ischemia/reperfusion injury. We evaluated the impact of the HIF-1α signaling pathway on allograft recovery during cadaveric KTx. MethodsBetween 1996 and 2015, 46 patients underwent cadaveric KTx. The expression levels of HIF-1α-related proteins, including phosphoinositide 3-kinase, phosphorylated (p)-Akt, p-mammalian target of rapamycin, p-Eukaryotic translation initiation factor 4E, p-S6 ribosomal protein, and HIF-1α, were immunohistochemically evaluated and semi-quantitatively scored in graft biopsy specimens after 1 hour of revascularization. Ten kidney biopsy specimens collected during donor nephrectomy for living KTx were used as controls. Delayed graft function (DGF) was defined as the need for dialysis within 1 week of KTx. We compared the staining scores of each protein and several clinical parameters between patients with and those without DGF. ResultsExpression levels of all six proteins in specimens after revasculization were elevated compared with those in controls. Thirty-five patients had DGF. Expression levels of PI3K, p-AKT, p-mTOR, p-eIF4E, and HIF-1α were significantly higher in patients without DGF than in those with DGF. Univariate analysis identified expression levels of p-Akt, p-S6, and HIF-1α, in addition to donor type (heart beating/non-heart beating), cold ischemic time, and donor age as significant predictors of DGF. Of these, only expression levels of HIF-1α and donor type were independently associated with DGF in multivariate analysis. ConclusionsUp-regulation of HIF-1α in allografts after reperfusion may be a predictor of early recovery after cadaveric KTx.

Kidney Intragraft Homing of De Novo Donor-Specific HLA Antibodies Is an Essential Step of Antibody-Mediated Damage but Not Per Se Predictive of Graft Loss.

Donor-specific HLA antibody (DSA)-mediated graft injury is the major cause of kidney loss. Among DSA characteristics, graft homing has been suggested as an indicator of severe tissue damage. We analyzed the role of de novo DSA (dnDSA) graft homing on kidney transplantation outcome. Graft biopsy specimens and parallel sera from 48 nonsensitized pediatric kidney recipients were analyzed. Serum samples and eluates from graft biopsy specimens were tested for the presence of dnDSAs with flow bead technology. Intragraft dnDSAs (gDSAs) were never detected in the absence of serum dnDSAs (sDSAs), whereas in the presence of sDSAs, gDSAs were demonstrated in 72% of biopsy specimens. A significantly higher homing capability was expressed by class II sDSAs endowed with high mean fluorescence intensity and C3d- and/or C1q-fixing properties. In patients with available sequential biopsy specimens, we detected gDSAs before the appearance of antibody-mediated rejection. In sDSA-positive patients, gDSA positivity did not allow stratification for antibody-mediated graft lesions and graft loss. However, a consistent detection of skewed unique DSA specificities was observed over time within the graft, likely responsible for the damage. Our results indicate that gDSAs could represent an instrumental tool to identify, among sDSAs, clinically relevant antibody specificities requiring monitoring and possibly guiding patient management.

Lung intragraft donor-specific antibodies as a risk factor for graft loss

The effect of donor-specific anti-human leukocyte antigen (HLA) antibodies (DSAs) on graft survival is recognized in lung transplantation, but not all serum DSAs appear to be harmful. We wondered whether in situ DSA detection from graft biopsy specimens could help in identifying lung transplant recipients (LTRs) at higher risk for graft loss. Class I and II HLA antibody single-antigen flow bead assays were performed in 53 LTRs to identify immunoglobulin G DSA in biopsy specimen eluates and in sera and to evaluate C1q binding ability of DSA in sera. Intragraft DSAs (gDSAs) were correlated with serum DSAs (sDSAs), clinical and histologic data, and graft survival. Twenty-eight (52.8%) LTRs had sDSAs, 12 (22.6%) had C1q-positive sDSAs, and 11 (20.8%) had gDSAs. Fifty sDSAs were found, among which 15 (30%) were C1q-positive and 14 (28%) were found in biopsy specimen eluates. One DSA was detected in the biopsy specimen only. Serum mean fluorescence intensity and biopsy fragment size were higher for sDSAs detected in biopsy specimens (p = 0.003 and p = 0.02, respectively). One-year post-biopsy graft survival was lower for LTRs with gDSAs (p = 0.008 by log-rank test). Presence of gDSA at the time of biopsy constituted a risk factor for graft loss in univariate (odds ratio, 6.67; 95% confidence interval [CI] 1.51-29.47; p = 0.008; hazard risk, 3.44; 95% CI, 1.47-8.01, p = 0.005) and multivariate (odds ratio, 5.85; 95% CI, 1.23-27.68; p = 0.03; hazard risk, 4.51; 95% CI, 1.83-11.13; p = 0001) analyses using logistic regression and a Cox proportional hazard model, respectively. In lung transplantation, gDSA appears to be a valuable biomarker to identify pathogenic DSA and LTRs with a higher risk for graft loss.

MP32-08 THE EFFECT OF HYPOXIA-INDUCIBLE FACTOR-1? EXPRESSION IN BIOPSY SPECIMEN AFTER REPERFUSION ON THE EARLY RECOVERY OF GRAFT FUNCTION AFTER CADAVERIC KIDNEY TRANSPLANTATION

You have accessJournal of UrologyTransplantation & Vascular Surgery: Renal Transplantation & Vascular Surgery II1 Apr 2016MP32-08 THE EFFECT OF HYPOXIA-INDUCIBLE FACTOR-1? EXPRESSION IN BIOPSY SPECIMEN AFTER REPERFUSION ON THE EARLY RECOVERY OF GRAFT FUNCTION AFTER CADAVERIC KIDNEY TRANSPLANTATION Teruyuki Oda, Takeshi Ishimura, and Masato Fujisawa Teruyuki OdaTeruyuki Oda More articles by this author , Takeshi IshimuraTakeshi Ishimura More articles by this author , and Masato FujisawaMasato Fujisawa More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2016.02.1303AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Ischemia/reperfusion injury during kidney transplantation delays allograft recovery. Hypoxia-inducible factor-1a (HIF-1a) is considered to be the key regulator of cell response to hypoxia and regulates several genes responsible for tissue protection. In this study, we evaluated the expression levels of major proteins mediating HIF-1a signaling by immunohistochemical staining of graft biopsy specimens at 1-h of revascularization during cadaveric kidney transplantation, and examined the correlation between these findings and recovery of allograft function. METHODS Between 1996 and 2015, 46 patients underwent cadaveric kidney transplantation at our institution. Of these, 15 patients received kidneys from heart beating donors (HBDs) and 31 from non-heart beating donors (NHBDs). Immunohistochemical staining was performed to evaluate the expression levels of HIF-1a-related proteins, including PI3K, phosphorylated (p)-Akt, p-mammalian target of rapamycin (mTOR), p-eIF4E, p-S6 ribosomal protein, and HIF-1a in graft biopsy specimens at 1 h of revascularization (1H). Based on the percentage of positive staining area in the specimen, immunohistochemical findings were scored from 0 to 3. 0-hour biopsy specimens from 10 who underwent living-donor kidney transplantation (0H) were used as control. Delayed graft function (DGF) was defined as the need for dialysis within the first week after kidney transplantation. We compared the staining score of each protein and several clinical parameters between patients with and without DGF. RESULTS Expression levels of all 6 proteins were elevated at 1 H compared with those at 0H, with significant differences for pAKT, pS6, and HIF-1a. Thirty five patients experienced DGF. We observed significant higher expression of all 6 proteins, in patients without DGF than in DGF patients. Univariate analysis identified the expression levels of p-Akt, p-S6, and HIF-1a, in addition to donor type (HBD/NHBD), cold ischemic time, and donor age as significant predictors of DGF. Of these 6 significant parameters, only the expression levels of HIF-1a and donor type were found to be independently associated with DGF on multivariate analysis. CONCLUSIONS In conclusion, up-regulation of HIF-1a in allograft biopsy specimens after reperfusion might be a predictor of early recovery of graft function in cadaveric kidney transplantation. © 2016FiguresReferencesRelatedDetails Volume 195Issue 4SApril 2016Page: e430 Advertisement Copyright & Permissions© 2016MetricsAuthor Information Teruyuki Oda More articles by this author Takeshi Ishimura More articles by this author Masato Fujisawa More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Renal Graft Fibrosis and Inflammation Quantification by an Automated Fourier-Transform Infrared Imaging Technique.

Renal interstitial fibrosis and interstitial active inflammation are the main histologic features of renal allograft biopsy specimens. Fibrosis is currently assessed by semiquantitative subjective analysis, and color image analysis has been developed to improve the reliability and repeatability of this evaluation. However, these techniques fail to distinguish fibrosis from constitutive collagen or active inflammation. We developed an automatic, reproducible Fourier-transform infrared (FTIR) imaging-based technique for simultaneous quantification of fibrosis and inflammation in renal allograft biopsy specimens. We generated and validated a classification model using 49 renal biopsy specimens and subsequently tested the robustness of this classification algorithm on 166 renal grafts. Finally, we explored the clinical relevance of fibrosis quantification using FTIR imaging by comparing results with renal function at 3 months after transplantation (M3) and the variation of renal function between M3 and M12. We showed excellent robustness for fibrosis and inflammation classification, with >90% of renal biopsy specimens adequately classified by FTIR imaging. Finally, fibrosis quantification by FTIR imaging correlated with renal function at M3, and the variation in fibrosis between M3 and M12 correlated well with the variation in renal function over the same period. This study shows that FTIR-based analysis of renal graft biopsy specimens is a reproducible and reliable label-free technique for quantifying fibrosis and active inflammation. This technique seems to be more relevant than digital image analysis and promising for both research studies and routine clinical practice.

Late Onset of Cholesterol Embolism Leading to Graft Failure After Renal Transplantation: Report of Two Cases

Cholesterol-crystal embolization (CE) usually presents as an acute or subacute multisystemic disease. When affecting native kidneys prognosis is poor, often leading to chronic kidney disease. Presentation in renal allografts is a rare condition although probably underdiagnosed. If renal CE originates from the recipient, allograft survival is usually good, whereas if the donor is the origin, graft dysfunction and subsequent graft loss are common. Associated risk factors are common to native and transplanted kidneys. We report 2 renal graft recipients of different cadaveric donors, both male and 68 years old, diagnosed with CE in renal grafts at 19 and 72 months after transplantation, respectively. They presented previous risk factors for CE, including severe atherosclerosis. They presented insidious and asymptomatic impairment of renal function initially. Renal graft biopsy specimens showed CE in the interlobular arteries. Potential triggers for CE were suspended and high doses of steroids were started. However, progressive decline in renal function and requirement of chronic dialysis occurred within the first year after diagnosis in both cases. Herein we discuss the causal or incidental role of CE in the graft failure of these cases, highlighting the serious outcome despite the recipient origin of the CE and the initiation of treatment.

Markers of Endothelial-to-Mesenchymal Transition: Evidence for Antibody-Endothelium Interaction during Antibody-Mediated Rejection in Kidney Recipients.

Antibody-mediated rejection (ABMR) is a leading cause of allograft loss. Treatment efficacy depends on accurate diagnosis at an early stage. However, sensitive and reliable markers of antibody-endothelium interaction during ABMR are not available for routine use. Using immunohistochemistry, we retrospectively studied the diagnostic value of three markers of endothelial-to-mesenchymal transition (EndMT), fascin1, vimentin, and heat shock protein 47, for ABMR in 53 renal transplant biopsy specimens, including 20 ABMR specimens, 24 cell-mediated rejection specimens, and nine normal grafts. We validated our results in an independent set of 74 unselected biopsy specimens. Endothelial cells of the peritubular capillaries in grafts with ABMR expressed fascin1, vimentin, and heat shock protein 47 strongly, whereas those from normal renal grafts did not. The level of EndMT marker expression was significantly associated with current ABMR criteria, including capillaritis, glomerulitis, peritubular capillary C4d deposition, and donor-specific antibodies. These markers allowed us to identify C4d-negative ABMR and to predict late occurrence of disease. EndMT markers were more specific than capillaritis for the diagnosis and prognosis of ABMR and predicted late (up to 4 years after biopsy) renal graft dysfunction and proteinuria. In the independent set of 74 renal graft biopsy specimens, the EndMT markers for the diagnosis of ABMR had a sensitivity of 100% and a specificity of 85%. Fascin1 expression in peritubular capillaries was also induced in a rat model of ABMR. In conclusion, EndMT markers are a sensitive and reliable diagnostic tool for detecting endothelial activation during ABMR and predicting late loss of allograft function.