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BACKGROUND: Organophosphate esters (OPEs) are flame retardants and plasticizers used in consumer products. OPEs are found ubiquitously throughout the environment with high concentrations in indoor house dust. Exposure to individual OPEs is associated with immune dysfunction, particularly in macrophages. However, OPEs exist as complex mixtures and the effects of environmentally relevant mixtures on the immune system have not been investigated. OBJECTIVES: The objectives of this study were to evaluate the toxicity of an environmentally relevant mixture of OPEs that models Canadian house dust on macrophages using phenotypic and functional assessments in vitro. METHODS: High-content live-cell fluorescent imaging for phenotypic biomarkers of toxicity in THP-1 macrophages treated with the OPE mixture was undertaken. We used confocal microscopy and cholesterol analysis to validate and expand on the observed OPE-induced lipid phenotype. Then, we used flow cytometry and live-cell imaging to conduct functional tests and uncover mechanisms of OPE-induced phagocytic suppression. Finally, we validated our THP-1 findings in human primary peripheral blood mononuclear cells (hPBMC) derived macrophages. RESULTS: Exposure to non-cytotoxic dilutions of the OPE mixture resulted in higher oxidative stress and disrupted lysosome and lipid homeostasis in THP-1 and primary macrophages. We further observed that phagocytosis of apoptotic cells in THP-1 and primary macrophages was lower in OPEexposed cells vs. controls. In THP-1 macrophages, phagocytosis of both Gram-positive and Gram-negative bacteria was also lower in OPE-exposed cells vs. controls. Additionally, the OPE mixture altered the expression of phagocytic receptors linked to the recognition of phosphatidylserine and pathogen-associated molecular patterns. DISCUSSION: The results of this in vitro study suggested that exposure to an environmentally relevant mixture of OPEs resulted in higher lipid retention in macrophages and poor efferocytic response. These effects could translate to enhanced foam cell generation resulting in higher cardiovascular mortality. Furthermore, bacterial phagocytosis was lower in OPE-exposed macrophages in an in vitro setting, which may indicate the potential for reduced bacterial clearance in models of infections. Taken together, our data provide strong evidence that mixtures of OPEs can influence the biology of macrophages and offer new mechanistic insights into the impact of OPE mixtures on the immune system. https://doi.org/10.1289/EHP13869, Introduction Manufacturers use organophosphate esters (OPEs), the most prominent class of flame retardants,in consumer and commercial products to prevent or reduce the spread of fire. (1,2) The use of OPEs [...]

Spinal muscular atrophy (SMA) is typically characterized as a motor neuron disease, but extraneuronal phenotypes are present in almost every organ in severely affected patients and animal models. Extraneuronal phenotypes were previously underappreciated, as patients with severe SMA phenotypes usually died in infancy; however, with current treatments for motor neurons increasing patient lifespan, impaired function of peripheral organs may develop into significant future comorbidities and lead to new treatment-modified phenotypes. Fatty liver is seen in SMA animal models, but generalizability to patients and whether this is due to hepatocyte-intrinsic survival motor neuron (SMN) protein deficiency and/or subsequent to skeletal muscle denervation is unknown. If liver pathology in SMA is SMN dependent and hepatocyte intrinsic, this suggests SMN-repleting therapies must target extraneuronal tissues and motor neurons for optimal patient outcome. Here, we showed that fatty liver is present in SMA patients and that SMA patient- specific induced pluripotent stem cell-derived hepatocyte-like cells were susceptible to steatosis. Using proteomics, functional studies, and CRISPR/Cas9 gene editing, we confirmed that fatty liver in SMA is a primary SMN-dependent hepatocyte- intrinsic liver defect associated with mitochondrial and other hepatic metabolism implications. These pathologies require monitoring and indicate the need for systematic clinical surveillance and additional and/or combinatorial therapies to ensure continued SMA patient health., Introduction Spinal muscular atrophy (SMA) is one of the most common monogenetic autosomal recessive neuromuscular genetic diseases, with a worldwide carrier frequency of approximately 1 in 52 and disease incidence [...]

Background Pathogenic mutations in the non-muscle single-headed myosin, myosin 1E (Myo1e), are a rare cause of pediatric focal segmental glomerulosclerosis (FSGS). These mutations are biallelic, to date only reported as homozygous variants in consanguineous families. Myo1e regulates the actin cytoskeleton dynamics and cell adhesion, which are especially important for podocyte functions. Methods DNA and RNA sequencing were used to identify novel MYO1E variants associated with FSGS. We studied the effects of these variants on the localization of Myo1e in kidney sections. We then analyzed the clinical and histological observations of all known pathogenic MYO1E variants. Results We identified a patient compound heterozygote for two novel variants in MYO1E and a patient homozygous for a deletion of exon 19. Computer modeling predicted these variants to be disruptive. In both patients, Myo1e was mislocalized. As a rule, pathogenic MYO1E variants map to the Myo1e motor and neck domain and are most often associated with steroid-resistant nephrotic syndrome in children 1-11 years of age, leading to kidney failure in 4-10 years in a subset of patients. The ultrastructural features are the podocyte damage and striking diffuse and global Alport-like glomerular basement membrane (GBM) abnormalities. Conclusions We hypothesize that MYO1E mutations lead to disruption of the function of podocyte contractile actin cables resulting in abnormalities of the podocytes and the GBM and dysfunction of the glomerular filtration barrier. The characteristic clinicopathological data can help to tentatively differentiate this condition from other genetic podocytopathies and Alport syndrome until genetic testing is done. Graphical abstract A higher resolution version of the Graphical abstract is available as Supplementary information., Author(s): Mira Krendel [sup.1] , Sabine Leh [sup.2] [sup.3] , Michael E. Garone [sup.1] , Alcia Edwards-Richards [sup.4] , Jen-Jar Lin [sup.4] , Damien Brackman [sup.5] , Per Knappskog [sup.6] [...]

* Context.--Modern RHD genotyping can be used to determine when patients with serologic weak D phenotypes have RHD gene variants at risk for anti-D alloimmunization. However, serologic testing, RhD interpretations, and laboratory management of these patients are quite variable. Objective.--To obtain interlaboratory comparisons of serologic testing, RhD interpretations, Rh immune globulin (RhIG) management, fetomaternal hemorrhage testing, and RHD genotyping for weak D-reactive specimens. Design.--We devised an educational exercise in which 81 transfusion services supporting obstetrics performed tube-method RhD typing on 2 unknown red blood cell challenge specimens identified as (1) maternal and (2) newborn. Both specimens were from the same weak D-reactive donor. The exercise revealed how participants responded to these different clinical situations. Results.--Of reporting laboratories, 14% (11 of 80) obtained discrepant immediate-spin reactions on the 2 specimens. Nine different reporting terms were used to interpret weak D-reactive maternal RhD types to obstetricians. In laboratories obtaining negative maternal immediate-spin reactions, 28% (16 of 57) performed unwarranted antiglobulin testing, sometimes leading to recommendations against giving RhIG. To screen for excess fetomaternal hemorrhage after a weak D-reactive newborn, 47% (34 of 73) of reporting laboratories would have employed a contraindicated fetal rosette test, risking false-negative results and inadequate RhIG coverage. Sixty percent (44 of 73) of laboratories would obtain RHD genotyping in some or all cases. Conclusions.--For obstetric and neonatal patients with serologic weak D phenotypes, we found several critical problems in transfusion service laboratory practices. We provide recommendations for appropriate testing, consistent immunohematologic terminology, and RHD genotype-guided management of Rh immune globulin therapy and RBC transfusions., In the United States and Canada, 0.06% to 2.2% of patients have red blood cells (RBCs) that type weakly reactive for RhD, termed 'serologic weak D phenotype.' (1-6) In past [...]

Host defense and inflammation are regulated by the NF-[kappa]B essential modulator (NEMO), a scaffolding protein with a broad immune cell and tissue expression profile. Hypomorphic mutations in inhibitor of NF-[kappa]B kinase regulatory subunit gamma (IKBKG) encoding NEMO typically present with immunodeficiency. Here, we characterized a pediatric autoinflammatory syndrome in 3 unrelated male patients with distinct X-linked IKBKG germline mutations that led to overexpression of a NEMO protein isoform lacking the domain encoded by exon 5 (NEMO-[DELTA]ex5). This isoform failed to associate with TANK binding kinase 1 (TBK1), and dermal fibroblasts from affected patients activated NF-[kappa]B in response to TNF but not TLR3 or RIG-I-like receptor (RLR) stimulation when isoform levels were high. By contrast, T cells, monocytes, and macrophages that expressed NEMO-[DELTA]ex5 exhibited increased NF-[kappa]B activation and IFN production, and blood cells from these patients expressed a strong IFN and NF-[kappa]B transcriptional signature. Immune cells and TNF-stimulated dermal fibroblasts upregulated the inducible IKK protein (IKKi) that was stabilized by NEMO-[DELTA]ex5, promoting type I IFN induction and antiviral responses. These data revealed how IKBKG mutations that lead to alternative splicing of skipping exon 5 cause a clinical phenotype we have named NEMO deleted exon 5 autoinflammatory syndrome (NDAS), distinct from the immune deficiency syndrome resulting from loss-of-function IKBKG mutations., Introduction The NF-[kappa]B essential modulator (NEMO/IKK-[gamma]) transduces signals in response to the stimulation of pattern recognition receptors, the TNF receptor superfamily, and lymphocyte antigen receptors, and thus plays a central [...]

Childhood obesity represents a public health crisis with serious long-term consequences. (1) The 'metabolism-disrupting chemical' hypothesis postulates that environmental chemicals with endocrine-disrupting ability have the potential to alter the body's [...]

Byline: Charuta. Godbole, Saket. Thaker, Santosh. Salagre, Vyankatesh. Shivane, Nithya. Gogtay, Urmila. Thatte Human paraoxonase 1 (PON1) enzyme protects against atherosclerosis by preventing low-density lipoprotein from oxidative modification. Upregulation of [...]

Background Co-occurrence of polycystic kidney disease and hyperinsulinemic hypoglycemia has been reported in children in a few families associated with a variant in the promotor of the PMM2 gene, at position -167 upstream of the coding sequence. PMM2 encodes phosphomannomutase 2, a key enzyme in N-glycosylation. While biallelic coding PMM2 mutations are involved in congenital disorder of glycosylation CDG1A, that particular variant in the promoter of the gene, either in the homozygous state or associated with a mutation in the coding exons of the gene, is thought to restrict the N-glycosylation defect to the kidney and the pancreas. Methods Targeted exome sequencing of a panel of genes involved in monogenic kidney diseases. Results We identified a PMM2 variant at position -167 associated with a pathogenic PMM2 variant in the coding exons in 3 families, comprising 6 cases affected with a cystic kidney disease. The spectrum of phenotypes was very broad, from extremely enlarged fetal cystic kidneys in the context of a COACH-like syndrome, to isolated cystic kidney disease with small kidneys, slowly progressing toward kidney failure in adulthood. Hypoglycemia was reported only in one case. Conclusion These data show that the PMM2 promotor variation, in trans of a PMM2 coding mutation, is associated with a wide spectrum of kidney phenotypes, and is not always associated with extra-renal symptoms. When present, extra-renal defects may include COACH-like syndrome. These data prompt screening of PMM2 in unresolved cases of fetal hyperechogenic/cystic kidneys as well as in cystic kidney disease in children and adults., Author(s): Guillaume Dorval [sup.1] [sup.2] , Cécile Jeanpierre [sup.2] , Vincent Morinière [sup.1] , Carole Tournant [sup.1] , Bettina Bessières [sup.3] , Tania Attié-Bittach [sup.3] [sup.4] , Jeanne Amiel [sup.4] [...]

Control of intracellular parasites responsible for malaria requires host IFN-[[gamma].sup.+]T-[bet.sup.+][CD4.sup.+] T cells (Th1 cells) with IL-10 produced by Th1 cells to mitigate the pathology induced by this inflammatory response. However, these IL-10-producing Th1 (induced type I regulatory [Tr1]) cells can also promote parasite persistence or impair immunity to reinfection or vaccination. Here, we identified molecular and phenotypic signatures that distinguished IL-10Th1 cells from IL-[10.sup.+]Tr1 cells in Plasmodium falciparum-infected people who participated in controlled human malaria infection studies, as well as C57BL/6 mice with experimental malaria caused by P. berghei ANKA. We also identified a conserved Tr1 cell molecular signature shared between patients with malaria, dengue, and graft-versus-host disease. Genetic manipulation of primary human [CD4.sup.+] T cells showed that the transcription factor cMAF played an important role in the induction of IL-10, while BLIMP-1 promoted the development of human [CD4.sup.+] T cells expressing multiple coinhibitory receptors. We also describe heterogeneity of Tr1 cell coinhibitory receptor expression that has implications for targeting these molecules for clinical advantage during infection. Overall, this work provides insights into [CD4.sup.+] T cell development during malaria that offer opportunities for creation of strategies to modulate [CD4.sup.+] T cell functions and improve antiparasitic immunity., Introduction Under homeostatic conditions, inflammation is controlled by immunoregulatory networks that prevent disease (1). These networks comprise interactions among specialized immune cells, parenchymal cells, and tissue-specific microbiomes (2, 3). Following [...]

Background Distal renal tubular acidosis (RTA) is typically caused by defects in ATP6V0A4, ATP6V1B1, and SLC4A1, accounting for 60-80% of patients. Genes recently implicated include FOXI1, ATP6V1C2, and WDR72, of which WDR72 is associated with dental enamel defects. Methods We describe 4 patients, from three unrelated consanguineous families, with RTA and amelogenesis imperfecta. Distal tubular acidification was evaluated by furosemide-fludrocortisone test, urine-to-blood PCO2 gradient and fractional excretion of bicarbonate. Exome sequencing was performed using a panel of genes implicated in human disease. Results Patients had polyuria, hypokalemia, hypercalciuria, and nephrocalcinosis, but metabolic acidosis varied in severity. Although all patients acidified urine to pH < 5.3 during furosemide-fludrocortisone test, urine-to-blood PCO.sub.2 gradient was < 20 mmHg during bicarbonate loading. All patients had transient proximal tubular dysfunction with urinary losses of phosphate and beta-2-microglobulin, and generalized aminoaciduria. Homozygous pathogenic truncating variants in WDR72 was detected in all probands. Conclusion Patients with WDR72 mutations show mild rate-dependent distal RTA with variable metabolic acidosis, and intact ability to acidify the urine on provocative testing. Concomitant proximal tubular dysfunction may be present. Mutations in WDR72 should be considered in patients with suspected distal RTA, especially if associated with dental defects., Author(s): Priyanka Khandelwal [sup.1] Mahesh V [sup.1] , Vijay Prakash Mathur [sup.2] , Sumantra Raut [sup.1] , Thenral S. Geetha [sup.3] , Sandhya Nair [sup.3] , Pankaj Hari [sup.1] , [...]