Severe congenital neutropenia (SCN) is a monogenic disorder. SCN patients are prone to recurrent life-threatening infections. The main causes of SCN are autosomal dominant mutations in the ELANE gene ...that lead to a block in neutrophil differentiation. In this study, we use CRISPR-Cas9 ribonucleoproteins and adeno-associated virus (AAV)6 as a donor template delivery system to repair the ELANEL172P mutation in SCN patient-derived hematopoietic stem and progenitor cells (HSPCs). We used a single guide RNA (sgRNA) specifically targeting the mutant allele, and an sgRNA targeting exon 4 of ELANE. Using the latter sgRNA, ∼34% of the known ELANE mutations can in principle be repaired. We achieved gene correction efficiencies of up to 40% (with sgELANE-ex4) and 56% (with sgELANE-L172P) in the SCN patient-derived HSPCs. Gene repair restored neutrophil differentiation in vitro and in vivo upon HSPC transplantation into humanized mice. Mature edited neutrophils expressed normal elastase levels and behaved normally in functional assays. Thus, we provide a proof of principle for using CRISPR-Cas9 to correct ELANE mutations in patient-derived HSPCs, which may translate into gene therapy for SCN.
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Using CRISPR-Cas9 and AAV6 donor vectors, Tran et al. achieve efficient gene correction of ELANE mutations in severe congenital neutropenia patient-derived hematopoietic stem and progenitor cells (HSPCs). ELANE-repaired HSPCs restored neutrophil differentiation in vitro and in vivo. Mature edited neutrophils show normal elastase expression and neutrophil functions.
Very‐low‐carbohydrate diet triggers the endogenous production of ketone bodies as alternative energy substrates. There are as yet unproven assumptions that ketone bodies positively affect human ...immunity. We have investigated this topic in an in vitro model using primary human T cells and in an immuno‐nutritional intervention study enrolling healthy volunteers. We show that ketone bodies profoundly impact human T‐cell responses. CD4+, CD8+, and regulatory T‐cell capacity were markedly enhanced, and T memory cell formation was augmented. RNAseq and functional metabolic analyses revealed a fundamental immunometabolic reprogramming in response to ketones favoring mitochondrial oxidative metabolism. This confers superior respiratory reserve, cellular energy supply, and reactive oxygen species signaling. Our data suggest a very‐low‐carbohydrate diet as a clinical tool to improve human T‐cell immunity. Rethinking the value of nutrition and dietary interventions in modern medicine is required.
SYNOPSIS
Ketogenic diet (KD) is characterized by a very limited uptake of carbohydrates, resulting in endogenous production of ketone bodies. This study identifies KD as a potent nutritional immunometabolic intervention to reprogram human T cell immunometabolism, favouring mitochondrial oxidative phosphorylation, thus enhancing both effector and regulatory T cell immune capacity and priming human T cells towards memory cell formation.
KD augmented human CD4+ and CD8+ T cell cytokine production and cell lysis capacity in vitro and in vivo.
Additionally, KD also enhanced regulatory T cell abundance and function, and primed human T cells to memory cell formation.
In response to KD, increased mitochondrial mass, ETC complex formation, aerobic oxidative phosphorylation capacity and ‐tightly controlled‐ ROS production was identified in human T cells.
Transcriptomic analysis revealed fundamental immunometabolic reprogramming of human CD4+ and CD8+ T cells after 3 weeks of KD.
Both, elevated bioenergetic capacity and ROS ‐serving as T‐cell second messenger molecules‐ provide the immunometabolic basis for enhanced T cell immunity on a KD.
Ketogenic diet (KD) is characterized by a very limited uptake of carbohydrates, resulting in endogenous production of ketone bodies. This study identifies KD as a potent nutritional immunometabolic intervention to reprogram human T cell immunometabolism, favouring mitochondrial oxidative phosphorylation, thus enhancing both effector and regulatory T cell immune capacity and priming human T cells towards memory cell formation.
Summary
Thrombocytopenia absent radii (TAR) syndrome is clearly defined by the combination of radial aplasia and reduced platelet counts. The genetics of TAR syndrome has recently been resolved and ...comprises a microdeletion on Chromosome 1 including the RBM8A gene and a single nucleotide polymorphism (SNP) either at the 5′ untranslated region (5′UTR) or within the first intron of RBM8A. Although phenotypically readily diagnosed after birth, the genetic determination of particular SNPs in TAR syndrome harbours valuable information to evaluate disease severity and treatment decisions. Here, we present clinical data in a cohort of 38 patients and observed that platelet counts in individuals with 5′UTR SNP are significantly lower compared to patients bearing the SNP in intron 1. Moreover, elevated haemoglobin values could only be assessed in patients with 5′UTR SNP whereas white blood cell count is unaffected, indicating that frequently observed anaemia in TAR patients could also be SNP‐dependent whereas leucocytosis does not correlate with genetic background. However, this report on a large cohort provides an overview of important haematological characteristics in TAR patients, facilitating evaluation of the various traits in this disease and indicating the importance of genetic validation for TAR syndrome.
A high proportion of patients with mucocutaneous bleeding diathesis and suspected inherited or acquired platelet disorder remain without diagnosis even after comprehensive laboratory testing. Since ...flow cytometry allows investigation of resting and activated platelets on the single cell level by requiring only minimal amounts of blood, this method has become an important assay within the diagnostic algorithm, especially in pediatrics. We therefore developed a standardized and modular flow cytometric approach that contributes to clarify impaired platelet function in a rational step-by-step manner.
Due to simultaneous analysis of four fluorophores in a basic panel design, we are able to readily detect the most common and clinically significant platelet disorders: Glanzmann thrombasthenia or Glanzmann-like diseases (fibrinogen receptor GPIIb-IIIa), Bernard-Soulier syndrome (von Willebrand-factor receptor complex GPIb-IX-V) and less well characterized β1-integrins that serve as the collagen, laminin or fibronectin receptor (CD29-CD49b, e and f, respectively). Platelet reactivity was investigated in response to the agonists adenosine diphosphate (ADP) and thrombin receptor activator peptide 6 (TRAP6) in suboptimal and optimal concentrations by quantifying surface expression of activation markers CD62P and CD63 as well as binding of PAC-1 antibody to the high affinity conformation of the fibrinogen receptor. For advanced diagnostic questions, several further modules were implemented: (i) calcium mobilization for evaluation of early signal transduction, (ii) a kinetically resolved mepacrine assay for estimation of delta-granule content and release, and (iii) a module to determine platelet reactivity upon additional agonists like the thromboxane A
2
-analogue U46619 or collagen. Blood withdrawn from a healthy control cohort allowed generating preliminary standard values for all parameters. The modules were validated by analysis of patients with known or suspected platelet defects (leukocyte-adhesion deficiency type III, Wiskott-Aldrich syndrome, acute myeloid leukemia, sickle cell disease and chronic immune thrombocytopenia).
Defects of platelet intracellular signaling can result in severe platelet dysfunction. Several mutations in each of the linked genes FERMT3 and RASGRP2 on chromosome 11 causing a Glanzmann‐like ...bleeding phenotype have been identified so far. We report on novel variants in two unrelated pediatric patients with severe bleeding diathesis—one with leukocyte adhesion deficiency type III due to a homozygous frameshift in FERMT3 and the other with homozygous variants in both, FERMT3 and RASGRP2. We focus on the challenging genetic and functional variant assessment and aim to accentuate the risk of obtaining misleading results due to the phenomenon of genetic linkage.
During the onset of acute inflammation, rapid trafficking of leukocytes is essential to mount appropriate immune responses towards an inflammatory insult. Monocytes are especially indispensable for ...counteracting the inflammatory stimulus, neutralising the noxa and reconstituting tissue homeostasis. Thus, monocyte trafficking to the inflammatory sites needs to be precisely orchestrated. In this study, we identify a regulatory network driven by miR-125a that affects monocyte adhesion and chemotaxis by the direct targeting of two adhesion molecules, i.e., junction adhesion molecule A (JAM-A), junction adhesion molecule-like (JAM-L) and the chemotaxis-mediating chemokine receptor CCR2. By investigating monocytes isolated from patients undergoing cardiac surgery, we found that acute yet sterile inflammation reduces miR-125a levels, concomitantly enhancing the expression of JAM-A, JAM-L and CCR2. In contrast, TLR-4-specific stimulation with the pathogen-associated molecular pattern (PAMP) LPS, usually present within the perivascular inflamed area, resulted in dramatically induced levels of miR-125a with concomitant repression of JAM-A, JAM-L and CCR2 as early as 3.5 h. Our study identifies miR-125a as an important regulator of monocyte trafficking and shows that the phenotype of human monocytes is strongly influenced by this miRNA, depending on the type of inflammatory stimulus.
Thrombocytopenia–absent radius (TAR) syndrome is characterized by hypomegakaryocytic thrombocytopenia and bilateral radial aplasia in the presence of both thumbs. Other frequent associations are ...congenital heart disease and a high incidence of cow’s milk intolerance. Evidence for autosomal recessive inheritance comes from families with several affected individuals born to unaffected parents, but several other observations argue for a more complex pattern of inheritance. In this study, we describe a common interstitial microdeletion of 200 kb on chromosome 1q21.1 in all 30 investigated patients with TAR syndrome, detected by microarray-based comparative genomic hybridization. Analysis of the parents revealed that this deletion occurred de novo in 25% of affected individuals. Intriguingly, inheritance of the deletion along the maternal line as well as the paternal line was observed. The absence of this deletion in a cohort of control individuals argues for a specific role played by the microdeletion in the pathogenesis of TAR syndrome. We hypothesize that TAR syndrome is associated with a deletion on chromosome 1q21.1 but that the phenotype develops only in the presence of an additional as-yet-unknown modifier (mTAR).
Complex immune dysregulation is a hallmark of sepsis. The occurring phases of immunosuppression and hyperinflammation require rapid detection and close monitoring. Reliable tools to monitor patient's ...immune status are yet missing. Currently, microRNAs are being discussed as promising new biomarkers in sepsis. However, no suitable internal control for normalization of miRNA expression by qPCR has been validated so far, thus hampering their potential benefit. We here present the first evaluation of endogenous controls for miRNA analysis in human sepsis. Novel candidate reference miRNAs were identified via miRNA microArray. TaqMan qPCR assays were performed to evaluate these microRNAs in T-cells and whole blood cells of sepsis patients and healthy controls in two independent cohorts. In T-cells, U48 and miR-320 proved suitable as endogenous controls, while in whole blood cells, U44 and miR-942 provided best stability values for normalization of miRNA quantification. Commonly used snRNA U6 exhibited worst stability in all sample groups. The identified internal controls have been prospectively validated in independent cohorts. The critical importance of housekeeping gene selection is emphasized by exemplary quantification of imuno-miR-150 in sepsis patients. Use of appropriate internal controls could facilitate research on miRNA-based biomarker-use and might even improve treatment strategies in the future.
The recombinant IL-1 receptor antagonist anakinra-currently approved for the treatment of autoinflammatory diseases-blocks IL-1β-mediated inflammatory signaling. As inflammation is a major driver of ...cancer, we hypothesized that anakinra might be able to mitigate glioblastoma (GBM) aggressiveness.
Primary GBM or T98G cells were incubated alone or with peripheral blood mononuclear cells (PBMCs) and were subsequently treated with IL-1β and/or anakinra. T cells were obtained by magnetic bead isolation. Protein and mRNA expression were quantified by SDS-PAGE, qRT-PCR, and ELISA, respectively. Cell proliferation and apoptosis were analyzed via flow cytometry. Chemotaxis was studied via time-lapse microscopy.
Upon IL-1β stimulation, anakinra attenuated proinflammatory gene expression in both GBM cells and PBMCs, and mitigated tumor migration and proliferation. In a more lifelike model replacing IL-1β stimulation by GBM-PBMC co-culture, sole presence of PBMCs proved sufficient to induce a proinflammatory phenotype in GBM cells with enhanced proliferation and migration rates and attenuated apoptosis. Anakinra antagonized these pro-tumorigenic effects and, moreover, reduced inflammatory signaling in T cells without compromising anti-tumor effector molecules.
By dampening the inflammatory crosstalk between GBM and immune cells, anakinra mitigated GBM aggressiveness. Hence, counteracting IL-1β-mediated inflammation might be a promising strategy to pursue.
Introduction/Objectives
Fertility preservation is a major concern for adolescent cancer patients; yet, educational gaps remain. Our intervention study examined whether specially designed educational ...materials regarding fertility preservation increase knowledge and empowerment of patients and parents.
Methods
Eleven paediatric‐oncological centres in four European countries agreed to enrol all eligible patients and parents in a questionnaire survey at 3 and 6 months after diagnosis. Treating physicians were surveyed on their medical consultation regarding fertility.
Results
Educational intervention increased knowledge in both patients (n = 113 and n = 101 in the control and intervention groups, respectively) and parents (n = 111 and n = 99 in the control and intervention groups, respectively), but the difference did not achieve statistical significance (knowledge difference patients: 5.6% (t0)/13.1% (t1); parents: 6.4% (t0)/3.8% (t1)). Parents of older patients (OR = 1.3, 95%CI = 1.1‐1.7) and higher educational groups (OR = 6.2, 95%CI = 2.1‐18.3) in the intervention group (OR = 1.9, 95%CI = 1.03‐3.7) achieved higher knowledge levels. Empowerment was significantly improved in both patients (p = 0.046, d = 0.27) and parents (p = 0.046, d = 0.48) in the intervention group.
Discussion/Conclusions
In our study, the use of specifically prepared flyers and brochures successfully raised the level of fertility preservation knowledge in parents of older patients as well as parents with higher educational levels. Overall, the intervention improved patient and parent empowerment. Subsequent projects will include simpler information and digital material to particularly reach out to younger and less educated individuals.
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