Deletion of Induces Xanthinuria with Obstructive Nephropathy and Major Metabolic Disorders in Mice.

Background: Xanthinuria type II is a rare autosomal purine disorder. This recessive defect of purine metabolism remains an under-recognized disorder.

Methods: Mice with targeted disruption of the molybdenum cofactor sulfurase () gene were generated to enable an integrated understanding of purine disorders and evaluate pathophysiologic functions of this gene which is found in a large number of pathways and is known to be associated with autism.

Safety, Tissue Distribution, and Metabolism of LNA-Containing Antisense Oligonucleotides in Rats.

Antisense oligonucleotides (ASOs) are chemically modified nucleic acids with therapeutic potential, some of which have been approved for marketing. We performed a study in rats to investigate mechanisms of toxicity after administration of 3 tool locked nucleic acid (LNA)-containing ASOs with differing established safety profiles. Four male rats per group were dosed once, 3, or 6 times subcutaneously, with 7 days between dosing, and sacrificed 3 days after the last dose.

Multiorgan Crystal Deposition of an Amphoteric Drug in Rats Due to Lysosomal Accumulation and Conversion to a Poorly Soluble Hydrochloride Salt.

Poor solubility of drug candidates mainly affects bioavailability, but poor solubility of drugs and metabolites can also lead to precipitation within tissues, particularly when high doses are tested. RO0728617 is an amphoteric compound bearing basic and acidic moieties that has previously demonstrated good solubility at physiological pH but underwent widespread crystal deposition in multiple tissues in rat toxicity studies. The aim of our investigation was to better characterize these findings and their underlying mechanism(s), and to identify possible screening methods in the drug development process.

Retrospective Post-mortem SARS-CoV-2 RT-PCR of Autopsies with COVID-19-Suggestive Pathology Supports the Absence of Lethal Community Spread in Basel, Switzerland, before February 2020.

Introduction: Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has rapidly spread around the world. While the first case was recorded in Hubei in December 2019, the extent of early community spread in Central Europe before this period is unknown. A high proportion of asymptomatic cases and undocumented infections, high transmissibility, and phylogenetic genomic diversity have engendered the controversial possibility of early international community spread of SARS-CoV-2 before its emergence in China.

Lamellar Inclusions within Hyperplastic Endoplasmic Reticulum in Benign Mesothelial Cells.

Introduction: In effusion cytology, mesothelial cells can occasionally present with striking intracytoplasmic accumulation of rod- and crystal-like cytoplasmic lamellar inclusions (LIs). Their nature and function are poorly understood, and their diagnostic relevance is unknown.

Objective: The aim of this study was to explore the nature of LIs in mesothelial cells and determine their prevalence and diagnostic utility in routine practice.

The Banff Working Group Classification of Definitive Polyomavirus Nephropathy: Morphologic Definitions and Clinical Correlations.

Polyomavirus nephropathy (PVN) is a common viral infection of renal allografts, with biopsy-proven incidence of approximately 5%. A generally accepted morphologic classification of definitive PVN that groups histologic changes, reflects clinical presentation, and facilitates comparative outcome analyses is lacking. Here, we report a morphologic classification scheme for definitive PVN from the Banff Working Group on Polyomavirus Nephropathy, comprising nine transplant centers in the United States and Europe.

Acute Rejection Phenotypes in the Current Era of Immunosuppression: A Single-Center Analysis.

Background: Besides 'definitive rejection', the Banff classification includes categories for 'suspicious for rejection' phenotypes. The aim of this study was to determine the frequency and phenotypes of rejection episodes in 316 consecutive renal transplants from 2009 to 2014 grouped into patients without/with pretransplant HLA-DSA (ptDSA, n = 251; ptDSA, n = 65).

Methods: All adequate indication (n = 125) and surveillance biopsies (n = 538) performed within the first year posttransplant were classified according to the current Banff criteria.

From the Cover: The Minipig is a Suitable Non-Rodent Model in the Safety Assessment of Single Stranded Oligonucleotides.

Non-human primates (NHPs) are currently considered to be the non-rodent species of choice for the preclinical safety assessment of single-stranded oligonucleotide (SSO) drugs. We evaluated minipigs as a potential alternative to NHPs to test the safety of this class of compounds. Four different phosphorothioated locked nucleic acid-based SSOs (3 antisense and 1 anti-miR), all with known safety profiles, were administered to minipigs using similar study designs and read-outs as in earlier NHP studies with the same compounds.

Impact of donor ABH-secretor status in ABO-mismatched living donor kidney transplantation.

Background: The ABO blood group is a major determinant in living donor kidney transplantation since AB antigens are expressed on renal tissue. Little attention has been directed to the ABH-secretor status of the donor kidney. As renal tissue is capable of secreting soluble ABH antigens in secretors, we examined the influence of the ABH-secretor status of kidney donors on outcome in ABO-mismatched living donor kidney transplantation.

Pathology of resolving polyomavirus-associated nephropathy.

Control of polyomavirus BK (BKV) is achieved by reducing immunosuppression allowing an effective BKV-specific T-cell response. The morphology of resolving BKV-associated nephropathy (PyVAN) has not been systematically investigated. Ninety-nine surveillance biopsies of 35 patients with BKV viremia treated exclusively by immunosuppression reduction were scored according to Banff criteria and grouped relative to BKV viremia as pre-, increasing, decreasing and post-BKV viremia.

Polyomavirus nephropathy: a brief review with special emphasis on clinico-patholgical aspects.

From 1995 Polyomavirus (PyV) nephropathy (PVN) has played an important role in solid organ transplant recipients. The disease is caused by a DNA virus, usually the BK variant, more rarely JC virus. In immune incompetent patients either latent endogenous virus is reactivated, or donated virus can multiply.

High incidence of rejection episodes and poor tolerance of sirolimus in a protocol with early steroid withdrawal and calcineurin inhibitor-free maintenance therapy in renal transplantation: experiences of a randomized prospective single-center study.

Immunosuppressive maintenance therapy after kidney transplantation leads to various undesired side effects such as calcineurin inhibitor (CNI)-associated nephrotoxicity or elevated cardiovascular risk due to posttransplantation diabetes and hypertension. These effects show negative impacts on long-term allograft function as well as patient morbidity and mortality. Therefore, we used an immunosuppressive regimen with early corticosteroid withdrawal (ESW), maintenance therapy containing tacrolimus, sirolimus (SRL), and mycophenolate sodium for 3 months followed by a prospective randomized trial comparing a CNI free versus a low-dose CNI therapy.

FAN1 mutations cause karyomegalic interstitial nephritis, linking chronic kidney failure to defective DNA damage repair.

Chronic kidney disease (CKD) represents a major health burden. Its central feature of renal fibrosis is not well understood. By exome sequencing, we identified mutations in FAN1 as a cause of karyomegalic interstitial nephritis (KIN), a disorder that serves as a model for renal fibrosis.

Outcome of fibrillary glomerulonephritis.

Questions Under Study: We assessed the long-term follow up of all the patients with fibrillary glomerulonephritis diagnosed since 1992 at our centre of reference for renal pathology in Basel.

Methods: We performed a retrospective surveillance study with mail questionnaire based follow-up of all patients with the diagnosis of fibrillary glomerulonephritis found in the database of the department of renal pathology in Basel from 1992 to 2007. The outcome was assessed in terms of endstage renal disease (ESRD), death, reduction of proteinuria and improvement of estimated glomerular filtration rate (eGFR).

Repeat true surveillance biopsies in kidney transplantation.

Background: Protocol biopsies are assigned to fixed points in time after transplantation irrespective of renal function. Usually, it is not known whether there is graft dysfunction at the time of biopsy. This study analyzes repeat protocol biopsies in the absence of any clinical signs of graft dysfunction at the time of biopsy (i.

Induction of Experimental Arthritis by Borrelial Lipoprotein and CpG Motifs: Are Toll-Like Receptors 2, 4, 9 or CD-14 Involved?

Bacterial lipoproteins and CpG-DNA are ligands for Toll-Like-Receptors (TLR) 2 and 9 respectively. Both classes of molecules were reported to induce experimental arthritis in rodents following direct intra-articular injection. Here we studied: 1) whether arthritis induction by Outer surface (Lipo)protein A (OspA) (B.

Histopathological patterns of nephrocalcinosis: a phosphate type can be distinguished from a calcium type.

Background: The etiology of nephrocalcinosis is variable. In this study, we wanted to elucidate whether the histopathological appearance of calcium phosphate deposits provides information about possible etiology.

Methods: Autopsy cases from the years 1988 to 2007 and native kidney biopsies from a 50-year period (1959-2008) with nephrocalcinosis were identified.

Renal amyloidosis revisited: amyloid distribution, dynamics and biochemical type.

Background: Renal amyloidosis results from protein misfolding and leads to progressive renal insufficiency. Few data are available concerning the relevance of the histomorphological patterns and the dynamics of the disease process.

Methods: Cases of renal amyloidosis in native kidney biopsies (n = 203) were retrospectively evaluated for the pattern of amyloid distribution, the extent of glomerular amyloid deposition and the amount of interstitial fibrosis and tubular atrophy.

Risk stratification by the virtual crossmatch: a prospective study in 233 renal transplantations.

The virtual crossmatch (virtual-XM) has been proposed for accurate identification of donor-specific HLA-antibodies, but large prospective studies assessing its value for pretransplant risk stratification are lacking. A total of 233 consecutive renal allograft recipients were prospectively stratified according to the virtual-XM. In patients with a negative virtual-XM (n=190, 82%), prospective cytotoxicity crossmatches (CDC-XM) were omitted, and they received standard immunosuppression.

Is monitoring of FOXP3 Treg cells in renal transplants during acute cellular rejection episodes useful?

Background: The FOXP3 (forkhead Box p3) transcription factor is a marker for T regulatory cells (Treg). During cellular immune responses, Treg are expected to increase in number to ultimately control and limit this response. In renal transplants massive infiltration by T cells is often seen during rejection crises.

Protein level expression of Toll-like receptors 2, 4 and 9 in renal disease.

Background: Toll-like receptors (TLR) recognize a variety of ligands, including pathogen-associated molecular patterns and link innate and adaptive immunity. Individual receptors can be up-regulated during infection and inflammation. We examined the expression of selected TLRs at the protein level in various types of renal disease.

Reducing immunosuppression preserves allograft function in presumptive and definitive polyomavirus-associated nephropathy.

Early detection of polyomavirus BK (BKV) viremia and reduction of immunosuppression is recommended for preventing polyomavirus-associated nephropathy (PyVAN), but systematic histological evaluations were not performed in previous studies. We routinely screen for decoy cells and, if positive, measure plasma BKV-loads. In a cohort of 203 consecutive renal transplantations performed from 2005-2008, 38 patients (19%) developed BKV-viremia and were treated with reduction of immunosuppression.