bluuebunny/crossref_metadata_2025_split huggingface dataset:
MO016CD28 AS A MARKER OF T CELL IMMUNOSENESCENCE IN PATIENTS ON HEMODIALYSIS
Authors: Lioulios Georgios , Sampani Erasmia , Daikidou Dimitra Vasileia , Xochelli Aliki , Kasimatis Efstratios , Mitsoglou Zoi , Stangou Maria , Fylaktou Asimina , Papagianni Aikaterini 
Published: May 2021

Abstract

Background and Aims
Reduced expression of CD28 molecule on CD4+ and CD8+ cells is a potential marker of senescence and has also been described in end stage renal disease (ESRD). Aim of the present study was to evaluate changes of CD28 expression on CD4+ and CD8+ cells in ESRD patients, and to assess possible effects of ageing and HD.

Method
Flow cytometric analysis was performed in 96 patients [M/F 54/42 Age 56.6(18-81)yrs] on HD to evaluate the expression of CD28 antigen on CD4+ and CD8+ cells. Proportions and absolute numbers of CD4+CD28null and CD8+CD28null cells were estimated, and results were correlated to patients age and time on HD. Patients with malignant or systemic disease were excluded, as those with inadequate HD (KT/V&lt;1,2), or recent (&lt;3months) infection. Results were compared to those of 27 healthy controls, similar age, sex, and race.

Results
HD patients had significantly reduced lymphocyte count (p&lt;0.001), percentage and total count of CD3+ cells (p=0.04, p&lt;0.0001, respectively) and CD4+ cells (p=0.005, p&lt;0.001, respectively). Percentage of CD4+CD28null and CD8+CD28null cells were both increased in patients compared to controls (p=0.009, p=0.01, respectively). However, although changes in CD8CD28null cells were evident early, even in &lt;2yrs, similar changes in CD4CD28null cells, appeared only after ≥2yrs on HD, (p=0.004).
Age of the patients had significant correlation with CD8+CD28null cells (r=0.4, p=0.001). In the older groups (&gt;40yrs) patients had significantly increased CD3+CD28null, CD4+CD28null and CD8+CD28null cells, compared to older controls (p=0.002, p=0.003, p=0.01, respectively).

Conclusion
CD28 expression is significantly reduced on CD4+ and CD8+ cells in HD patients. CD8+CD28null expression is significantly affected early, both by age and HD, while CD28 expression on CD4+ seems to be more stable, as CD4+CD28null cells increase in older patients, after long time on HD.
MO017THERAPEUTICAL POTENTIAL OF ENZYME REPLACEMENT: NEW INSIGHTS AND PERSPECTIVES IN HUMAN ENDOTHELIAL CELLS TREATED WITH CHLOROQUINE
Authors: Gregorio Paulo C , Cunha Regiane , Biagini Gilson , Bosquetti Bruna , Budag Julia , Ortiz Alberto , Sanchez-Nino Maria Dolores , Barreto Fellype , Stinghen Andréa E M 
Published: May 2021

Abstract

Background and Aims
COVID-19 is a pandemic with no end in sight. There is only one approved antiviral agent but global stocks are deemed insufficient. Despite in vitro antiviral activity, clinical trials of chloroquine and hydroxychloroquine were disappointing, and they may even impair outcomes. Chloroquine causes zebroid deposits reminiscent of Fabry disease (α-galactosidase A deficiency) and endothelial cells are key targets of COVID-19. The study aims to investigate in vitro the effect of enzyme replacement therapy (ERT) in chloroquine-induced endothelial dysfunction.

Method
We have explored the effect of chloroquine on cultured endothelial cells and its modulation by recombinant α-galactosidase A (agalsidase-β). Following dose-response studies, 0.5 μg/mL chloroquine was added to cultured human endothelial cells. Neutral red and Lysotracker were used to assess lysosomes. Cytotoxicity was evaluated by the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) - MTT assay and cell stress by assessing reactive oxygen species (ROS) and nitric oxide (NO). In endothelial cells, chloroquine induced dose-dependent cytotoxicity at in vitro test concentrations for COVID-19 therapy.

Results
Chloroquine significantly induced the accumulation of acid organelles (P&lt;0.05), increased ROS levels, and decreased NO production (P&lt;0.05), in vitro. These adverse effects of chloroquine on endothelial cell biology were decreased by agalsidase-β (P&lt;0.05).

Conclusion
Chloroquine-induced endothelial cell cytotoxicity and stress is attenuated by agalsidase-β treatment. This suggests that endothelial cell injury may contribute to the failure of chloroquine as therapy for COVID-19 and may be at least in part related to causing dysfunction of the lysosomal enzyme α-galactosidase A.
MO013SENESCENCE-LIKE CHANGES IN B CELL PHENOTYPE IN HEMODIALYSIS PATIENTS
Authors: Lioulios Georgios , Fylaktou Asimina , Xochelli Aliki , Sampani Erasmia , Tsouchnikas Ioannis , Giamalis Panagiotis , Daikidou Dimitra Vasileia , Mitsoglou Zoi , Papagianni Aikaterini , Stangou Maria 
Published: May 2021

Abstract

Background and Aims
End Stage Renal Disease (ESRD) is characterized by susceptibility to infections, high prevalence of cancer and cardiovascular disease and poor response to vaccination. All of the above are potential consequences to compromised immune function seen in ESRD and demonstrated by profound immune cells phenotype changes, resembling the natural course of senescence; therefore termed immunosenescence. Whereas alterations of T cells in ESRD have been largely studied, there are insufficient data regarding B cell immunity. In this study we evaluate the effects of hemodialysis (HD) on B cells, in terms of untimely expression of immunosenescent phenotype.

Method
B cells phenotype was analyzed by flow cytometry in 25 ESRD patients on HD (M/F 15/10, Mean Age 59±14.7yrs). Patients on HD with systemic diseases, malignancy or recent (&lt;3 months) episode of infection were excluded. Subpopulations, including naïve (IgD+CD27-), IgM memory (IgD+CD27+), switched memory (IgD-CD27+) and late memory (IgD-CD27-) B cells were determined. Findings were compared to 12 healthy controls of similar age.

Results
In HD patients a severe B lymphopenia was observed; a decrease in B cells both percentage (6.5±2.7% vs 11.9±4.5%, p&lt;0.0001) and absolute number [88(53) vs 229(271) cells/μl, p&lt;0.0001]. Naïve and late memory B cells proportions were similar between patients and controls, however, absolute number was significantly lower in HD patients for both subsets [55(54)vs118(216) cells/μl, p=0.006, and 7(7) vs 21(24) cells/μl, respectively, p=0.001]. Switched memory B cells declined in HD both in terms of percentage [15.7(11.7)% vs 25.7(18.9)%, p:0.03] and absolute number [13(10) vs 59(64) cells/μl, p=0.00].

Conclusion
Chronic hemodialysis results in B cell phenotype alterations similar to normal aging. Switched memory B cells, the predictors of optimal antibody responses are significantly reduced, and this may act as an additional factor to relative immune deficiency of dialysis patients.
MO038SCARF EXPRESSION IN KIDNEY DISEASE
Authors: Carriazo Sol , Sanchez-Nino Maria Dolores , Perez Gomez Maria Vanessa , Castañeda-Infante Laura , Martin Catalina , Gonzalez-Martin Guillermo , Gomá Elena , Gonzalez-Rivera Marina , Ortiz Alberto 
Published: May 2021

Abstract

Background and Aims
Chronic kidney disease (CKD) is the most common risk factor for lethal COVID19 and the risk factor that most increases the risk of death of COVID19 patients. Additionally, acute kidney injury (AKI) is frequent in COVID19 and AKI increases the risk of death. However, the underlying cellular and molecular mechanisms of such increased risk are unclear. SARS-CoV-2 and coronavirus-associated receptors and factors (SCARFs) are required for and/or regulate (in a positive or negative manner) coronary cell entry and/or viral replication. We have now studied changes in the expression of genes encoding for SCARF in the context of acute and chronic kidney disease.

Method
Data mining of in-house (experimental models of AKI -folic acid nephropathy- and CKD -Unilateral ureteral obstruction- in mice) and publicly available databases (Nephroseq, published single cell transcriptomics studies) of kidney tissue transcriptomics as well as the Protein Atlas database.

Results
Out of 28 SCARF genes identified by Singh et al (Cell Reports 2020), 26 were represented in the experimental AKI database. Of them 7 (27%) were differentially expressed during AKI (FDR &lt;0.05), 4 of them upregulated and 3 downregulated (Figure 1.A). Additionally, 27 were represented in the experimental CKD database. Of them 17 (63%) were differentially expressed during experimental CKD, 6 of them upregulated and 11 downregulated (Figure 1.B). Two genes were consistently upregulated (Ctsl and Ifitm3) and two consistently downregulated (Tmprss2 and Top3b) in both experimental AKI and CKD (Figure 1.A and B). They encode cathepsin L, interferon induced transmembrane protein 3, transmembrane serine protease 2, DNA topoisomerase III beta, respectively. Single cell transcriptomics databases localized Ctsl expression mainly to podocytes and tubular cells while protein atlas showed clear tubular staining. The main site of Ifitm3 was endothelium in both datasets and it was also localized to leukocytes by single cell transcriptomics. Tmprss2 was mainly localized to tubular cells in both datasets while Top3b was widely expressed in parenchymal renal cells, endothelium and leucocytes in single cell transcriptomics. Increased kidney expression of Ifitm3 and decreased expression of Tmprss2 and Top3b were confirmed in diverse CKD datasets in Nephroseq.

Conclusion
Both AKI and CKD are associated with differential expression of SCARF genes in kidney tissue, the impact of CKD appearing to be larger. Characterization of these changes and their functional impact in kidney tissue and beyond the kidneys may provide clues to the increased risk of severe or lethal COVID19 in kidney disease patients.
Kidney SCARF gene expression
MO039IDENTIFICATION OF A RECURRENT SYNONYMOUS GENETIC VARIANT IN NPHP3 LEADING TO NEPHRONOPHTHISIS AND CONGENITAL HEPATIC FIBROSIS
Authors: Olinger Eric , Al Alawi Intisar , Molinari Elisa , Ali Faqeih Eissa , Al Hamed Mohamed , Barroso-Gil Miguel , Wilson Ian , Research Consortium Genomics England , Sayer John 
Published: May 2021

Abstract

Background and Aims
Whole exome sequencing (WES) is becoming part of routine clinical and diagnostic practice and has been extensively applied in research studies as well as for diagnostic utility to detect various novel genes and variants. Filtering of variants and scoring variants in terms of pathogenicity still represents a major challenge and may explain why ∼50% of patients remain without diagnosis after initial assessment.

Method
In this study, we performed WES to determine the genetic cause of a hepato-renal ciliopathy syndrome in a genetically unsolved consanguineous family from Oman with 2 affected children. For variants filtering and annotation Qiagen Clinical Insight tool was used. Database searches for identical alleles in patients with similar phenotypes were performed using Genomics England, UK Biobank and a Saudi Arabian cohort. RNA studies were used to confirm a splicing defect. This research was made possible through access to the data and findings generated by the 100,000 Genomes Project and from UK Biobank, a major biomedical database.

Results
Initial bioinformatic analysis of WES data from 2 affected sibs excluded obvious pathogenic variants in known genes associated with primary ciliopathy syndromes with liver and kidney phenotypes. However, by manual curation of variants in candidate genes, a rare homozygous synonymous allele in NPHP3 was identified (c.2805C&gt;T; p.(Gly935Gly)), mid-exon 20 and within a region of shared homozygosity on chromosome 3. Correct segregation was confirmed via Sanger sequencing in the parents and the 2 affected sibs. The variant was rare in gnomAD (2/251374 alleles) and was found heterozygously in just one individual within the UK Biobank cohort of 200,000 exomes. Using various in silico tools, the allele was shown to activate a cryptic splice donor site in the middle of exon 20. RT-PCR with sequencing of parental whole blood RNA confirmed alternative splicing leading to frameshift p.Gly935GlyfsTer47. The identical homozygous allele was identified in 2 additional unsolved families within the Genomics England 100,000 Genomes Project and in 1 Saudi Arabian family with similar hepato-renal phenotypes.

Conclusion
This study shows that automated filtering of WES data may exclude synonymous variants which are pathogenic, especially if they are mid-exon. Here we identified a recurrent synonymous NPHP3 variant leading to a splice defect as the cause of a hepato-renal ciliopathy phenotype in four families. In unsolved cases, rare synonymous alleles in candidate genes need to be reassessed for impact on RNA splicing and possible pathogenicity.
MO040REAL-WORLD USE OF TOLVAPTAN AND ITS IMPACT ON EGFR IN A NORTH EAST UK COHORT
Authors: Gkekas Eleftherios , Tang Tsz Yau Tiffany , Green Alan , Davidson Han , Fraser Rachel , Sayer John , Srivastava Shalabh 
Published: May 2021

Abstract

Background and Aims
Autosomal dominant polycystic kidney disease (ADPKD) is a cause of progressive chronic kidney failure (CKD) and end stage kidney disease (ESKD). Tolvaptan has been shown within clinical trials to slow down decline of kidney function in patients with ADPKD at risk of rapid progression. We performed a retrospective review of a cohort of ADPKD patients who had been established on tolvaptan therapy to determine its efficacy in a real- world clinic setting.

Method
Subjects who had a clinical diagnosis of ADPKD and who had been established on tolvaptan for a period of &gt;18 months were reviewed retrospectively in terms of their eGFR. Subjects were between the ages of 18-65 years old and both males and females were included in this study. Other inclusion criteria involved a pre-treatment slope of &lt;-2.5 ml/min/1.73m2 based on readings for a 3 year period, a pre-treatment eGFR of 30-90 ml/min/1.73m2 and ability to tolerate tolvaptan treatment and be maintained on treatment for at least12 months. We calculated based on eGFR slopes, predicted time to reach CKD stage 5 with and without tolvaptan therapy. Given this was a retrospective review, eGFR were estimated during clinic visits whilst on tolvaptan treatment, rather than after a drug washout period.

Results
The cohort of patients included 20 from Newcastle upon Tyne Hospitals and 2 from Sunderland Royal Infirmary. The mean rate of eGFR decline prior to treatment was -5.92 ml/min/1.73m2 per year for the cohort. Following tolvaptan treatment, the average decline in eGFR was reduced to -2.57 ml/min/1.73m2 per year. Therefore, tolvaptan lessened average eGFR decline within this cohort by 3.35 ml/min/1.73m2 per year, gaining 7 years and 9 months delay until CKD stage 5. The majority of patients (n=19) received full dose tolvaptan (90mg/30mg). At an individual level, 3 patients failed to respond at all to tolvaptan, with no improvement in decline of GFR and 2 others had a very mild improvement only (change in eGFR slope of &lt;0.5 ml/min/1.73m2 per year). 6 patients had a dramatic improvement in eGFR slope (&gt;5 ml/min/1.73m2 per year).

Conclusion
The real life use of tolvaptan seemed to give a dramatic improvement in eGFR slopes, much more than the previously reported clinical studies have shown. This may be in part due to patient selection and only including patients who tolerated therapy, a “tolvaptan clinic” effect where great personal care is given to these patients and to excellent compliance with medication. Reasons for both non-response and exaggerated response need to be evaluated carefully to determine how individualisation of tolvaptan therapy can be best used.
MO043HYPERURICEMIA IS RELATIVELY COMMON IN CHILDREN WITH HNF1B MUTATION, BUT ITS UTILITY AS A CLINICALLY USEFUL MARKER FOR PREDICTING THE MUTATION IS LIMITED
Authors: Kołbuc Marcin , Bieniaś Beata , Habbig Sandra , Kołek Mateusz , Szczepanska Maria , Kiliś-Pstrusińska Katarzyna , Wasilewska Anna , Adamczyk Piotr , Motyka Rafał , Tkaczyk Marcin , Sikora Przemysław , Beck Bodo B , Zaniew Marcin 
Published: May 2021

Abstract

Background and Aims
Hyperuricemia is recognized as an important feature of HNF1B nephropathy, and could serve as a good marker of the disease facilitating selection of patients for genetic testing. However, neither the casual relationship nor its predictive value have been proven yet. We thus decided to assess this in a cohort of children with renal malformations with (mut+) and without HNF1B mutations (mut-).

Method
We performed a retrospective analysis of clinical and genetic results of pediatric patients tested for HNF1B mutations, whose data were collected in a national registry. Hyperuricemia was assessed by using the newest, age- and gender-dependent reference values for serum uric acid (sUA) in children.

Results
A total of 108 children were included into the study comprising 43 mut+ patients, and 65 mut- subjects. Mean sUA was higher in mut+ than in mut- subjects (p = 0.006), and hyperuricemia was more prevalent in those with HNF1B mutations (42.5% vs. 15.4%, p = 0.002). Renal phenotype analysis revealed renal hyperechogenicity and multicystic dysplastic kidney disease were more frequent in mut+ patients, but no influence of any renal features/phenotypes on hyperuricemia was found. The two patient cohorts were different with regard to pancreatic anomaly (p &lt; 0.001), glucose metabolism disorders (p = 0.003), hypomagnesemia (p &lt; 0.001), and hyperparathyroidism (p &lt; 0.001). In a multivariate linear stepwise regression model, eGFR, fractional excretion of uric acid, impairments in glucose metabolism and pancreatic anomaly were found to be independent predictive variables of sUA (R2=0.67, F=13.27, p &lt; 0.001). Mutation was not identified as a determinant of sUA. After exclusion of patients with hyperglycemia and/or pancreatic malformations, the difference in hyperuricemia prevalence did not persist between mut+ and mut-. Potential of hyperuricemia for mutation prediction was tested in a model with hypomagnesemia and hyperparathyroidism, which showed an accuracy of 85% (sensitivity: 83%, specificity: 86%). Adding hyperuricemia to the model did not increase the accuracy (79%; sensitivity: 77%, specificity: 82%). Information gain, which informs selective potential of each parameter, was the lowest for hyperuricemia (0.34 compared with 0.99 and 0.63 for hyperparathyroidism and hypomagnesemia, respectively).

Conclusion
Hyperuricemia is relatively common in children with HNF1B mutation, however its direct association with this molecular defect remains still unproven. Its dependence on renal function and hyperglycemia diminishes the utility as a clinically useful marker for predicting HNF1B disease.
MO047STABLE EGFR IN PATIENTS WITH PRIMARY HYPEROXALURIA TYPE 1 TREATED WITH LUMASIRAN, REGARDLESS OF KIDNEY FUNCTION AT START OF TREATMENT
Authors: Hayes Wesley , Garrelfs Sander , Sas David , Lieske John , Ngo Taylor , Gansner John , McGregor Tracy , Frishberg Yaacov 
Published: May 2021

Abstract

Background and Aims
Primary hyperoxaluria type 1 (PH1) is a rare genetic disorder characterized by hepatic oxalate overproduction. Excess oxalate is excreted by the kidneys, leading to recurrent kidney stones, nephrocalcinosis, and progressive kidney disease. Patients with PH1 generally experience a slow decline in kidney function over time that can be punctuated by abrupt worsening precipitated by infection, obstructing stones, or dehydration. Approximately half of patients with PH1 progress to kidney failure by early adulthood, and nearly all by 60 years of age. Lumasiran is an RNAi therapeutic indicated for the treatment of PH1 in all age groups. In clinical trials, treatment with lumasiran resulted in substantial reductions in urinary and plasma oxalate in pediatric and adult patients, with an acceptable safety profile. This analysis evaluates the change in kidney function of patients with PH1 with an eGFR of ≥30 mL/min/1.73m2 enrolled in clinical trials of lumasiran.

Method
We analyzed kidney function from 75 patients with PH1, age ≥12 months old, eGFR ≥30 mL/min/1.73m2, enrolled in 3 clinical trials of lumasiran (Phase 2 open-label extension, and Phase 3 ILLUMINATE-A and ILLUMINATE-B). In these trials, eGFR was calculated with the Modification of Diet in Renal Disease (MDRD) Study equation in adults or the bedside Schwartz equation in children. The effect of lumasiran on eGFR was assessed by baseline eGFR subgroup: ≥90, &lt;90, 60 to &lt;90, 45 to &lt;60, and 30 to &lt;45 mL/min/1.73m2.

Results
Of 75 patients available for analysis, 46 were treated with lumasiran from the start of the study through the Month 12 visit. eGFR remained stable in all eGFR subgroups. Patients with eGFR ≥90 mL/min/1.73m2 at baseline (N=16) demonstrated fluctuations in mean values by timepoint, with a mean change (95% CI) from baseline of -1 (-8, 6) mL/min/1.73m2 at Month 12. In patients with eGFR &lt;90 mL/min/1.73m2 (N=30), no change in mean eGFR from baseline was observed at Month 12; the mean change (95% CI) was 0 (-3, 3). When evaluating subgroups with impaired kidney function, variations in the mean change were observed at Month 12 due to small sample sizes. For patients with eGFR 60 to &lt;90 mL/min/1.73m2 (N=22), the mean change (95% CI) was -2 (-5, 1). For patients with eGFR 45 to &lt;60 mL/min/1.73m2 (N=5), the mean change (95% CI) was 3 (-8, 14). For patients with eGFR 30 to &lt;45 mL/min/1.73m2 (N=3), the mean change (95% CI) was 9 (7, 11).

Conclusion
Patients with PH1 had stable kidney function over time with lumasiran treatment, regardless of kidney function at baseline. Given the progressive kidney function decline that is characteristic of PH1, the eGFR stability observed during 12 months of treatment with lumasiran is encouraging. Kidney function will continue to be monitored for the duration of the lumasiran clinical trials.