Deciphering the shift from benign to active relapsing-remitting multiple sclerosis: Insights into T regulatory cell dysfunction and apoptosis regulation.

BACKGROUND: Relapsing-remitting multiple sclerosis (RRMS), a common demyelinating disease among young adults, follows a benign course in 10-15% of cases, where patients experience minimal neurological disability for a decade following disease onset. However, there is potential for these benign cases to transition into a clinically active, relapsing state. OBJECTIVE: To elucidate the biological mechanisms underlying the transition from benign to active RRMS using gene expression analysis. METHODS: We employed complementary-DNA microarrays to examine peripheral-blood gene expression patterns in patients with benign MS, defined as having a disease duration exceeding 10 years and an Expanded Disability Status Scale (EDSS) score of ≤3.0. We compared the gene expression pattern between patients who switched to active disease (Switching BMS) with those who maintained a benign state (Permanent-BMS) during an additional 5-year follow-up. RESULTS: We identified two primary mechanisms linked to the transition from benign MS to clinically active disease. The first involves the suppression of regulatory T cell activity, and the second pertains to the dysfunction of nuclear receptor 4 A family-dependent apoptosis. These mechanisms collectively contribute to an augmented autoimmune response and increased disease activity. CONCLUSIONS: The intricate gene regulatory networks that operate in switching-BMS are related to suppression of immune tolerance and aberrant apoptosis. These findings may lead to new therapeutic targets to prevent the escalation to active disease.

Biliary strictures post pediatric liver transplantation-incidence and risk factors in a single tertiary referral transplant center.

BACKGROUND: Biliary strictures are a significant cause of morbidity and graft loss in pediatric liver transplant recipients. Risk factors for the development of biliary strictures are not fully established. We aimed to evaluate the incidence of biliary strictures and treatment modalities outcomes and to identify potential risk factors for occurrence. METHODS: Pediatric patients who underwent liver transplantation in the single tertiary pediatric liver transplant center in Israel were evaluated. We compared demographics, presentation, laboratory results, imaging, treatment, and outcomes between patients with and without biliary stricture. Multivariate regression analyses were used to identify risk factors for biliary strictures. RESULTS: Among 121 pediatric liver transplant patients, 65 (53.7%) were males; the median age at the time of liver transplantation was 43 (3-215) months. Fifteen patients (12.4%) had biliary strictures following transplantation. One (7%) patient with biliary stricture was treated via endoscopic retrograde cholangiopancreatography, and 12 patients (80%) underwent interventions via a percutaneous transhepatic approach. Nine of the 12 patients were treated successfully, requiring one or multiple procedures, while the remaining had surgery or laser therapy. Risk factors for the development of biliary strictures were biliary leak, acute cellular rejection, and the presence of two biliary anastomoses. CONCLUSIONS: In our cohort, the presence of two biliary anastomoses and post-transplant complications including acute cellular rejection and early biliary leaks were associated with biliary strictures in pediatric liver transplantation recipients. Percutaneous transhepatic interventions result in good outcomes in most patients.

Implementing living-donor pediatric liver transplantation in Southern Vietnam: 15-year results and perspectives.

BACKGROUND: ND2 in Ho Chi Minh City is currently the only public center that performs PLT in Southern Vietnam. In 2005, the first PLT was successfully performed, with support from Belgian experts. This study reviews the implementation of PLT at our center and evaluates the results and challenges. METHODS: Implementation of PLT at ND2 required medico-surgical team building and extensive improvement of hospital facilities. Records of 13 transplant recipients from 2005 to 2020 were studied retrospectively. Short- and long-term complications, as well as the survival rates, were reported. RESULTS: The mean follow-up time was 8.3 ± 5.7 years. Surgical complications included one case of hepatic artery thrombosis that was successfully repaired, one case of colon perforation resulting in death from sepsis, and two cases of bile leak that were drained surgically. PTLD was observed in five patients, of whom three died. There were no cases of retransplantation. The 1-year, 5-year, and 10-year patient survival rates were 84.6%, 69.2%, and 69.2%, respectively. There were no cases of complication or death among the donors. CONCLUSION: Living-donor PLT was developed at ND2 for providing a life-saving treatment to children with end-stage liver disease. Early surgical complication rate was low, and the patient survival rate was satisfactory at 1 year. Long-term survival decreased considerably due to PTLD. Future challenges include surgical autonomy and improvement of long-term medical follow-up with a particular emphasis on prevention and management of Epstein-Barr virus-related disease.

Mapping brain volume change across time in primary-progressive multiple sclerosis.

PURPOSE: Detection and prediction of the rate of brain volume loss with age is a significant unmet need in patients with primary progressive multiple sclerosis (PPMS). In this study we construct detailed brain volume maps for PPMS patients. These maps compare age-related changes in both cortical and sub-cortical regions with those in healthy individuals. METHODS: We conducted retrospective analyses of brain volume using T1-weighted Magnetic Resonance Imaging (MRI) scans of a large cohort of PPMS patients and healthy subjects. The volume of brain parenchyma (BP), cortex, white matter (WM), deep gray matter, thalamus, and cerebellum were measured using the robust SynthSeg segmentation tool. Age- and gender-related regression curves were constructed based on data from healthy subjects, with the 95% prediction interval adopted as the normality threshold for each brain region. RESULTS: We analyzed 495 MRI scans from 169 PPMS patients, aged 20-79 years, alongside 563 exams from healthy subjects aged 20-86. Compared to healthy subjects, a higher proportion of PPMS patients showed lower than expected brain volumes in all regions except the cerebellum. The most affected areas were BP, WM, and thalamus. Lower brain volumes correlated with longer disease duration for BP and WM, and higher disability for BP, WM, cortex, and thalamus. CONCLUSIONS: Constructing age- and gender-related brain volume maps enabled identifying PPMS patients at a higher risk of brain volume loss. Monitoring these high-risk patients may lead to better treatment decisions and improve patient outcomes.

Age-related blood transcriptional regulators affect disease progression in pediatric multiple sclerosis.

BACKGROUND: Pediatric onset multiple sclerosis patients (POMS) are defined as multiple sclerosis with an onset before the age of 18 years. Compared to adult onset multiple sclerosis (AOMS), POMS has more severe disease activity at onset, but better recovery. Little is known about the molecular mechanism responsible for the differences in the clinical presentations. METHODS: Peripheral Blood Mononuclear Cells samples were taken from 22 POMS patients (mean age 14.1 ± 2.4 years, 15 females, 7 male), and 16 AOMS patients, (mean age 30.8 ± 6.1 years,10 females, 6 males), and gene-expression were analyzed using Affymetrix Inc. HU-133-A2 microarrays. Differentially Expressed Genes (DEGs) that significantly distinguished between POMS and AOMS with pvalue <0.05 after false discovery rate correction were evaluated using Partek software. Twenty-one matched age and gender control was applied to clarify age-related changes. Clinical assessment was performed by analysis of expanded disability status scale (EDSS) and brain MRI lesion loads. Gene functional analysis was performed by Ingenuity Pathway Analysis software. RESULTS: Compared to AOMS, POMS had higher EDSS (3.0 IQR 2.0-3.0 and 2.0 IQR 2.0-3.0, p = 0.005), volume of T1 (2.72 mm3, IQR 0.44-8.39 mm3 and 0.5 mm3 IQR 0-1.29 mm3 respectively, p = 0.04) and T2 (3.70 mm3, IQR 1.3-9.6 and 0.96 mm3, IQR 0.24-4.63 respectively, p = 0.02) brain MRI lesions. The POMS transcriptional profile was characterized by 551 DEGs, enriched by cell cycling, B lymphocyte signaling and senescent pathways (p < 0.02). Of these, 183 DEGs significantly correlated with T2 lesions volume. The POMS MRI correlated DEGs (n = 183) and their upstream regulators (n = 718) has overlapped with age related DEGs obtained from healthy subjects (n = 497). This evaluated common DEGs (n = 29) defined as POMS age-related regulators, suggesting to promote effect on disease severity. CONCLUSION: Our finding of higher transcriptional levels of genes involved in cell cycle, cell migration and B cell proliferation that promoted by transcriptional level of age-associated genes and transcription factors allows better understanding of the more aggressive clinical course that defines the POMS.

COVID-19 Alpha Variant (B.1.1.7): Humoral, memory B and T cells in COVID-19 pediatric convalescents.

BACKGROUND: Studies of anti-SARS-CoV-2 humoral and adaptive response in COVID-19 non-vaccinated pediatric convalescents are controversial and further evidence from the pediatric population are needed. OBJECTIVES: To elucidate SARS-CoV-2 humoral and memory B- and T-cells responses in pediatric convalescents as compared with the adult. METHODS: Blood samples were obtained from 80 non-vaccinated, IgG-positive, COVID-19 convalescents (age 8.0-61.0 years), 4.0 months from onset. Frequency of responders and magnitudes of SARS-COV-2 IgG, memory B-cells (MBC) and IFNg- and IL2-secreting memory T-cells (MTC) in response to immuno-dominant peptide pools in pediatric, young adults and middle-aged adults with onset age 8-18 years (N = 20), 19-39 years (N = 30) and 40-61 years (N = 30), respectively, were analyzed. SARS-CoV-2 IgG were detected by ELISA (Euroimmun, Germany). MBC, IFNg-, IL2- and IFNg+IL2-secreting MTC (IFNg-MTC, IL2-MTC and IFNg+IL2-MTC) were detected using FluoroSpot (Mabtech, Sweden). RESULTS: MBC level was lower in pediatric as compared with the middle-aged adults (median 12.75 interquartile range [IQR] 4.27-33.7 and 32.0 IQR 6.0-124.2, respectively, p = .003). MBC level in young adults was lower than in middle-aged adults (median 18.5 IQR 1.7-43.8 and 32.0 IQR 6.0-124.2, respectively, p = .006). The level of IL2-MTC was lower in the pediatric group as compared with middle aged-adults (median 2.1 IQR 0-16.9 and 28.6 IQR 11-49.6, respectively, p < .03) and in young adults lower than in middle-aged adults (median 1.45 IQR 0-18.6 and 28.6 IQR 11-49.6, respectively, p = .02). In addition, the level of IFNg-MTC was lower in pediatric as compared with young adults (median 4.25 IQR 0.0-15.0 and 20.9 IQR 0-75.2, respectively, p = .05). The level of IgG was comparable between pediatric and both young and middle-aged adult groups (4.82 ± 2.95, 3.70 ± 2.65 and 4.9 ± 2.94, respectively, p > .34). CONCLUSION: Non-vaccinated COVID-19 pediatric convalescents have lower adaptive immune responses than adults sustaining the recommendation for vaccination of the pediatric population.

Early post-liver transplant thrombocytopenia in children: Clinical characteristics and significance.

BACKGROUND: Post-liver transplant thrombocytopenia is common and associated with worse outcome in adults. In children, however, the prevalence, course, and significance of post-liver transplantation thrombocytopenia are not described. Therefore, we aimed to assess this phenomenon in children. METHODS: A retrospective chart review of children who underwent liver transplantation at a single tertiary center between 2004 and 2021. RESULTS: Overall, 130 pediatric liver transplantations were reviewed. During the first 28 POD, thrombocytopenia was evident in 116 (89%, 95% CI 83%-94%). The median nadir platelet count was 54 K/µl (IQR: 37-99). Nadir platelet count was reached in half the patients by the third POD (IQR: 1-6). In multivariate analysis, preoperative platelet count (p = .024), volume of intraoperative packed cell transfusion (p = .045), and hypersplenism (p = .007) were associated with lower postoperative platelet counts. Patients with platelet count lower than the 50th centile on the first POD suffered from a more complicated course leading to a longer PICU admission (p = .039). CONCLUSIONS: Early post-liver transplant thrombocytopenia appears to be common in children and associated with preoperative thrombocytopenia, hypersplenism, and higher intraoperative blood transfusion volumes. A low first POD platelet count (<86 K/µl) was found to be independently associated with a more complicated postoperative course, suggesting the need for heightened surveillance.

Portal plate bile duct diameter in biliary atresia is associated with long-term outcome.

PURPOSE: Kasai portoenterostomy (KPE) is the only treatment currently available for biliary atresia (BA). Age at KPE and surgical experience are prognostic factors for a successful KPE. Here, we aimed to assess whether the size of bile ductules at the porta hepatis during KPE correlates with KPE success and transplant-free survival (TFS). METHODS: A retrospective analysis of patients diagnosed with BA during 2000-2019. Porta hepatis biopsies were reviewed for diameters of five representative ducts, and a mean ductal diameter (MDD) was calculated. Laboratory values including pre- and postoperative bilirubin levels were analyzed. RESULTS: The cohort included 77 patients; for 33, ductal plate biopsy was available. KPE was successful in six of eight patients with MDD ≥ 50 µm, and in five of 25 with MDD < 50 µm, p = 0.008, OR = 12.0 (95% CI 1.83-78.3). Ten-year survival with native liver was higher in patients with MDD ≥ 50 µm than in patients with MDD < 50 µm, p < 0.001, HR 0.038 (95% CI 0.007-0.207). Direct bilirubin < 1 mg/dl 3 months post-KPE was associated with improved 2-year post-KPE TFS (27.7% vs. 13.9%, p < 0.0001). CONCLUSIONS: MDD ≥ 50 µm correlates with KPE success and a higher rate of TFS. Direct bilirubin < 1 mg/dl 3 months post-operation may serve as a marker of successful biliary excretion, and a predictor of 2-year TFS.

COVID-19 vaccination in patients with multiple sclerosis: What we have learnt by February 2021.

BACKGROUND: Since vaccination against coronavirus disease 2019 (COVID-19) became available, risks related to vaccinating patients with multiple sclerosis (MS) need to be carefully assessed. OBJECTIVE: Characterize safety and occurrence of immediate relapses following COVID-19 vaccination in a large cohort of MS patients. METHODS: We assessed the safety of BNT162b2 COVID-19 vaccination in adult MS patients. RESULTS: Between 20 December 2020 and 25 January 2021, 555 MS patients received the first dose of BNT162b2 vaccine and 435 received the second dose. There were three cases of COVID-19 infection encountered after the first dose. Safety profile of COVID-19 vaccine was characterized by pain at the injection site, fatigue, and headache. No increased risk of relapse activity was noted over a median follow-up of 20 and 38 days after first and second vaccine doses, respectively. The rate of patients with acute relapse was 2.1% and 1.6% following the first and second doses, respectively, similar to the rate in non-vaccinating patients during the corresponding period. Mild increase in the rate of adverse events was noted in younger patients (18-55 years), among patients with lower disability (Expanded Disability Status Scale (EDSS) ⩽3.0), and in patients treated with immunomodulatory drugs. CONCLUSION: COVID-19 BNT162b2 vaccine proved safe for MS patients. No increased risk of relapse activity was noted.

Convalescent Whole Blood Donors Screening Strategies for Providing Efficient and Safe COVID-19 Survivors' Plasma and Other Blood Components.

BACKGROUND: During the coronavirus disease-2019 (COVID-19) pandemic outbreak our blood bank developed protocols to guarantee accurate blood components to COVID-19 patients. OBJECTIVES: To provide convalescent whole blood donor screening strategies for patients recovering from COVID-19. METHODS: We recruited COVID-19 recovering patients who met our defined inclusion criteria for whole blood donation. All blood units were screened for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) RNA by real time reverse transcription polymerase chain reaction (RT-PCR) and SARS-COV-2 immunoglobulin G (IgG) antibodies against the S1 domain. RESULTS: We screened 180 blood units from patients recovering from COVID-19. All results were negative for SARS-CoV-2 RNA and 87.2% were positive for SARS-COV-2 IgG antibodies in the plasma. CONCLUSIONS: Blood component units from recovering COVID-19 patients are safe. Plasma units with positive IgG antibodies could serve as an efficient passive immunization for COVID-19 patients. Moreover, in the face of increased transfusion demand for treatment of anemia and coagulation dysfunction in critical ill COVID-19 patients, red blood cells units and random platelets units from convalescent donors can be safely transfused.

RAM-589.555 favors neuroprotective and anti-inflammatory profile of CNS-resident glial cells in acute relapse EAE affected mice.

BACKGROUND: Targeting RNA polymerase-1 (POL1) machinery is a new strategy for suppression of multiple sclerosis (MS) relapse activity. Oral administration of POL1 inhibitor RAM-589.555, which is characterized by high permeability and bioavailability in naïve mice, ameliorates proteolipid protein (PLP)-induced experimental autoimmune encephalomyelitis (EAE) by suppressing activated autoreactive lymphocytes. We assessed the accessibility of RAM-589.555 to the central nervous system (CNS) of EAE-mice and further investigated its immunomodulatory effects on CNS-resident astro- and micro-glial cells in-vitro and in-vivo. METHODS: Effects of RAM-589.555 on activated microglia and astrocyte viability, proliferation, and secretion of neurotrophic factors were assessed in-vitro. The pharmacokinetic of RAM-589.555 was evaluated in the blood and central nervous system (CNS) of EAE-affected mice. High-dimensional single-cell mass cytometry was applied to characterize the effect of RAM-589.555 on EAE-affected mice's CNS-resident micro- and astroglial cells and CNS-infiltrating immune cells, which were obtained seven days after RAM-589.555 administration at EAE onset. Simultaneously, the expression level of pre-rRNA, the POL1 end product, was assessed in blood cells, microglia, and astrocytes to monitor RAM-589.555 effects. RESULTS: RAM-589.555 demonstrated blood and CNS permeability in EAE mice. In-vitro, incubation with 400 nM of RAM-589.555 significantly reduced viability and proliferation of lipopolysaccharide (LPS)-activated microglia by 70% and 45% (p < 0.05), respectively, while tumor necrosis factor α (TNFα)-activated astrocytes were not affected. The secretion of neurotrophic factors was preserved. Furthermore, 7 days after administration of RAM-589.555 at EAE onset, the level of pre-rRNA transcript in peripheral blood mononuclear cells (PBMC) was decreased by 38.6% (p = 0.02), while levels of pre-rRNA transcript in microglia and astrocytes remained unchanged. The high-dimensional single-cell mass cytometry analysis showed decreased percentages of CNS-resident microglia and astrocytes, diminished pro-inflammatory cytokines (IL-1ß, IL-6, IL-12, IL-17, TNFα, and IFNγ), and an increase of their anti-inflammatory cytokines (IL-4, IL-10, and TGFß) in RAM-589.555-treated compared to vehicle-treated mice (p < 0.05). CONCLUSIONS: These data correlate RAM-589.555-induced clinical amelioration and its CNS-permeability to decreased CNS-inflammation, and decreased micro- and astrogliosis, while restoring micro- and astroglial anti-inflammatory and neuroprotective capacity.

Cytokine prediction of mortality in COVID19 patients.

Coronavirus disease 2019 (COVID19) is a life-threatening infection with uncertain progression and outcome. Assessing the severity of the disease for worsening patients is of importance in making decisions related to supportive mechanical ventilation and aggressive treatments. This was a prospective, non-randomized study that included hospitalized patients diagnosed with COVID19. Pro-inflammatory cytokines were assessed during hospitalization, and we calculated a prediction paradigm for 30-day mortality based on the serum levels of interleukin1ß (IL1ß), interleukin6 (IL6), interleukin8 (IL8), and tumor necrosis factor alpha (TNFα) measured by next-generation ELISA. Data of 71 COVID19 patients, mean age 62 years, SD13.8, 50 males, 21 females, were analyzed. Twelve (16.9%) patients died within 7-39 days of their first COVID19 positive nasopharyngeal test. Levels of IL6 and TNFα were significantly higher in patients that did not survive. IL6 predicted mortality at the cut-off value of 163.4 pg/ml, with a sensitivity of 91.7% and specificity of 57.6%. Our findings demonstrate that IL6 expression is significant for the prediction of 30-day mortality in hospitalized COVID19 patients and, therefore, may assist in treatment decisions.

Flow-controlled fluoroscopic angiography for the assessment of vascular integrity in bioengineered kidneys.

Perfusion decellularization has been proposed as a promising method for generating nonimmunogenic organs from allogeneic or xenogeneic donors. Several imaging modalities have been used to assess vascular integrity in bioengineered organs with no consistency in the methodology used. Here, we studied the use of fluoroscopic angiography performed under controlled flow conditions for vascular integrity assessment in bioengineered kidneys. Porcine kidneys underwent ex vivo angiography before and after perfusion decellularization. Arterial and venous patencies were defined as visualization of contrast medium (CM) in distal capillaries and renal vein, respectively. Changes in vascular permeability were visualized and quantified. No differences in patency were detected in decellularized kidneys compared with native kidneys. However, focal parenchymal opacities and significant delay in CM clearance were detected in decellularized kidneys, indicating increased permeability. Biopsy-induced leakage was visualized in both groups, with digital subtraction angiography revealing minimal CM leakage earlier than nonsubtracted fluoroscopy. In summary, quantitative assessment of vascular permeability should be coupled with patency when studying the effect of perfusion decellularization on kidney vasculature. Flow-controlled angiography should be considered as the method of choice for vascular assessment in bioengineered kidneys. Adopting this methodology for organs premodified ex vivo under normothermic machine perfusion settings is also suggested.

The Wnt/ß-catenin pathway determines the predisposition and efficiency of liver-to-pancreas reprogramming.

Transdifferentiation (TD) is the direct reprogramming of adult cells into cells of alternate fate and function. We have previously shown that liver cells can be transdifferentiated into beta-like, insulin-producing cells through ectopic expression of pancreatic transcription factors (pTFs). However, the efficiency of the process was consistently limited to <15% of the human liver cells treated in culture. The data in the current study suggest that liver-to-pancreas TD is restricted to a specific population of liver cells that is predisposed to undergo reprogramming. We isolated TD-predisposed subpopulation of liver cells from >15 human donors using a lineage tracing system based on the Wnt response element, part of the pericentral-specific promoter of glutamine synthetase. The cells, that were propagated separately, consistently exhibited efficient fate switch and insulin production and secretion in >60% of the cells upon pTF expression. The rest of the cells, which originated from 85% of the culture, resisted TD. Both populations expressed the ectopic pTFs with similar efficiencies, followed by similar repression of hepatic genes. Our data suggest that the TD-predisposed cells originate from a distinct population of liver cells that are enriched for Wnt signaling, which is obligatory for efficient TD. In TD-resistant populations, Wnt induction is insufficient to induce TD. An additional step of chromatin opening enables TD of these cells. CONCLUSION: Liver-to-pancreas TD occurs in defined predisposed cells. These cells' predisposition is maintained by Wnt signaling that endows the cells with the plasticity needed to alter their transcriptional program and developmental fate when triggered by ectopic pTFs. These results may have clinical implications by drastically increasing the efficacy of TD in future clinical uses. (Hepatology 2018).

Residual disability after severe relapse in people with multiple sclerosis treated with disease-modifying therapy.

BACKGROUND: The rate of post-relapse residual disability in patients with relapsing-remitting multiple sclerosis (RRMS) treated with disease-modifying drugs (DMD) has not been studied. OBJECTIVE: To assess relapse residual disability in DMD-treated RRMS patients. METHODS: We followed DMD-treated RRMS patients presenting with acute relapse who received high-dose steroids. Increases in Expanded Disability Status Scale (EDSS) of at least 2.0, 1.0-1.5 or 0.5 were defined as severe, moderate or mild relapses, respectively. The proportions of patients with post-relapse residual disability defined as the failure to regain pre-relapse neurological status at 1, 4 and 12 months were evaluated. RESULTS: Out of 1672 relapses in DMD-treated RRMS patients, 17% were severe. In patients who presented with a severe relapse, we observed post-relapse residual disability of at least 1.0 EDSS point in 60.1%, 55.9% and 48.2% of patients at 1, 2 and 12 months of follow-up, respectively. Post-relapse residual disability of at least 2.0 EDSS points was observed in 37.4%, 30.7% and 20.7% of patients after 1, 2 and 12 months, respectively. CONCLUSION: A high rate of incomplete recovery was seen 12 months following severe relapse among RRMS patients and may contribute to the accumulation of long-term disability.

Risk factors for early invasive fungal infections in paediatric liver transplant recipients.

Invasive fungal infections (IFIs) postliver transplantation are a frequent cause of morbidity and mortality; however, studies reporting on these infections in the paediatric population are scarce. To investigate the incidence and risk factors of IFIs in paediatric liver transplant recipients during the early posttransplantation period (≤3 months). Data were collected for all paediatric liver transplant recipients registered in a national transplantation center from 2004 to 2014. Using a stepwise logistic regression to identify independent risk factors for IFIs, a predictive model was formulated. Ten IFIs were identified in 81 liver transplant recipients (12.3%) all occurring during the first month posttransplantation. Candida species were responsible for nine cases (90%), of which four were non-albicans Candida (44%). Significant risk factors were identified; recipient of multiple blood product transfusions during transplantation, prolonged use of indwelling intravenous catheter, prolonged IV antibiotic treatment, surgical complications, pulse steroid treatment and living donor liver transplantation. The predictive model used two clinical parameters to define high-risk patients: a living donor transplantation and duration of IV antibiotic treatment (area under the ROC curve 0.918). IFIs are a significant complication occurring in the first month posttransplantation. Future studies are required to assess efficacy of targeted antifungal prophylaxis in high risk patients.

Transplantation of Livers from Old Donors: Pushing the Envelope Beyond the Seventh Decade.

BACKGROUND: The lack of organs for liver transplantation has prompted transplant professionals to study potential solutions, such as the use of livers from donors older than 70 years. This strategy is not widely accepted because potential risks of vascular and biliary complications and recurrence of hepatitis C. OBJECTIVES: To examine the efficacy and safety of liver grafts from older donors for transplantation. METHODS: A retrospective analysis of data on 310 adults who underwent deceased donor liver transplantation between 2005 and 2015 was conducted. We compared graft and recipient survival, as well as major complications, of transplants performed with grafts from donors younger than 70 years (n=265, control group) and those older than 70 years (n=45, older-donor group), followed by multivariate analysis, to identify risk factors. RESULTS: There was no significant difference between the control and older-donor group at 1, 5, and 10 years of recipient survival (79.5% vs. 73.3%, 68.3% vs. 73.3%, 59.2% vs. 66.7%, respectively) or graft survival (74.0% vs. 71.0%, 62.7% vs. 71.0%, 54.8% vs. 64.5%, respectively). The rate of biliary and vascular complications was similar in both groups. Significant risk factors for graft failure were hepatitis C (hazard ratio [HR] = 1.92, 95% confidence interval [95%CI] 1.16-2.63), older donor age (HR = 1.02, 95%CI 1.007-1.031), and male gender of the recipient (HR = 1.65, 95%CI 1.06-2.55). CONCLUSIONS: Donor age affects liver graft survival. However, grafts from donors older than 70 years may be equally safe if cold ischemia is maintained for less than 8 hours.

[ABO INCOMPATIBLE KIDNEY TRANSPLANTATION].

INTRODUCTION: With the introduction of new therapies, the ABO barrier for kidney transplantation has been breached. In the recent decade the reported results with ABO incompatible (ABOi) kidney transplantation are similar to ABO compatible transplantation. We report on our initial experience with ABOi kidney transplantation performed at the Rabin Medical Center. METHODS: During the period 3/2010 to 4/2015, 22 patients with PRA 0% underwent ABOi living-donor kidney transplantation. This group was compared to 325 non-sensitized live-donor transplant recipients of ABO-match transplants performed at the same period. The desensitization protocol included rituximab (375mg/kg/m2) and three sets of plasmapheresis every other day with IVIG (0.5g/kg) after each plasmapheresis. We compared graft and patient survivals, antibody mediated rejection (AMR) and graft function between the two groups. RESULTS: Graft survival rates at 1, 3 and 5 years in the ABOi group were 95.5% at all intervals and 99.4% for the 1st year and 97.9% at 3 and 5 years after transplant (p=ns). Patient survival rates were 100% at all intervals and 100%, 98.3% and 97.5% at 1,3, and 5 years (p=ns). Two patients (9.1%) in the ABOi group experienced antibody mediated rejection (AMR), one lost his graft. In the ABO-matched group only two patients (0.85%) experienced AMR (p<0.05). Creatinine levels at followup were not statistically different between the groups. CONCLUSIONS: ABO incompatible kidney transplantation provides an additional option for transplant with excellent results. Strict monitoring of antibody levels should be conducted after ABOi transplantation to timely intervene and prevent AMR.

Host cell virus entry mechanisms enhance anti-JCV-antibody switch in natalizumab-treated multiple sclerosis patients.

Estimating the individual risk for the development of progressive multifocal leukoencephalopathy (PML) in anti-John Cunningham virus (JCV) antibody-negative patients with multiple sclerosis (MS) treated with natalizumab is a major challenge. A serological conversion occurring under treatment from anti-JCV antibody-negative to positive status may significantly increase this risk. We investigated changes in peripheral blood cells' gene expression induced by natalizumab treatment in anti-JCV antibody-negative MS patients and tested blood transcriptional profile that characterizes patients predisposed to antibody switch under natalizumab treatment. After 3 years of natalizumab treatment, 24.6 % of anti-JCV antibody-negative MS patients switched to become anti-JCV antibody-positive (JCV switchers). Natalizumab induced 946 and 1186 significantly differentiating genes in JCV switchers and non-switchers, respectively. In JCV switchers, the signature was enriched by over-expression of genes associated with the first stages of viral entry to host cells including macropinocytosis (p = 1.82E-06), virus entry via endocytosis (p = 1.60E-06), clathrin-mediated endocytosis (p = 1.13E-04), and caveolar-mediated endocytosis (p = 4.50E-04) pathways. Further analysis to identify pre-existing transcriptional differences that characterize future JCV switchers prior to treatment initiation also demonstrated a transcriptional signature enriched by similar viral entry mechanisms. These findings, verified in an additional independent cohort of natalizumab-treated patients, could lead to future identification of patients that remain anti-JCV antibody-negative thus allowing safe continuation of treatment, as well as the development of future targeted therapeutic interventions to reduce the risk of PML.

Living Donor Liver Transplantation in Children: Surgical and Immunological Results in 250 Recipients at Université Catholique de Louvain.

OBJECTIVES: To evaluate the outcome of pediatric living donor liver transplantation (LDLT) regarding portal vein (PV) reconstruction, ABO compatibility, and impact of maternal donation on graft acceptance. BACKGROUND: LDLT and ABO-mismatched transplantation constitute feasible options to alleviate organ shortage in children. Vascular complications of portal hypoplasia in biliary atresia (BA) and acute rejection (AR) are still major concerns in this field. METHODS: Data from 250 pediatric LDLT recipients, performed at Cliniques Universitaires Saint-Luc between July 1993 and June 2012, were collected retrospectively. Results were analyzed according to ABO matching and PV complications. Uni- and multivariate analyses were performed to study the impact of immunosuppression, sex matching, and maternal donation on AR rate. RESULTS: Overall, the 10-year patient survival rate was 93.2%. Neither patient or graft loss nor vascular rejection, nor hemolysis, was encountered in the ABO nonidentical patients (n = 58), provided pretransplant levels of relevant isoagglutinins were below 1/16. In BA recipients, the rate of PV complications was lower after portoplasty (4.6%) than after truncal PV anastomosis (9.8%) and to jump graft interposition (26.9%; P = 0.027). In parental donation, maternal grafts were associated with higher 1-year AR-free survival (55.2%) than paternal grafts (39.8%; P = 0.041), but only in BA patients. CONCLUSIONS: LDLT, including ABO-mismatched transplantation, constitutes a safe and efficient therapy for liver failure in children. In BA patients with PV hypoplasia, portoplasty seems to constitute the best technique for PV reconstruction. Maternal donation might be a protective factor for AR.