A longitudinal single-cell atlas of treatment response in pediatric AML

Pediatric acute myeloid leukemia (pAML) is characterized by heterogeneous cellular composition, driver alterations and prognosis. Characterization of this heterogeneity and how it affects treatment response remains understudied in pediatric patients. We used single-cell RNA sequencing and single-cell ATAC sequencing to profile 28 patients representing different pAML subtypes at diagnosis, remission and relapse. At diagnosis, cellular composition differed between genetic subgroups. Upon relapse, cellular hierarchies transitioned toward a more primitive state regardless of subtype. Primitive cells in the relapsed tumor were distinct compared to cells at diagnosis, with under-representation of myeloid transcriptional programs and over-representation of other lineage programs. In some patients, this was accompanied by the appearance of a B-lymphoid-like hierarchy. Our data thus reveal the emergence of apparent subtype-specific plasticity upon treatment and inform on potentially targetable processes.

Machine learning optimized multiparameter radar plots for B-cell acute lymphoblastic leukemia minimal residual disease analysis

BACKGROUND

Flow cytometry is widely used for B-ALL minimal residual disease (MRD) analysis given its speed, availability, and sensitivity; however, distinguishing B-lymphoblasts from regenerative B-cells is not always straightforward. Radar plots, which project multiple markers onto a single plot, have been applied to other MRD analyses. Here we aimed to develop optimized radar plots for B-ALL MRD analysis.

METHODS

We compiled Children's Oncology Group (COG) flow data from 20 MRD-positive and 9 MRD-negative B-ALL cases (enriched for hematogones) to create labeled training and test data sets with equal numbers of B-lymphoblasts, hematogones, and mature B-cells. We used an automated approach to create hundreds of radar plots and ranked them based on the ability of support vector machine (SVM) models to separate blasts from normal B-cells in the training data set. Top-performing radar plots were compared with PCA, t-SNE, and UMAP plots, evaluated with the test data set, and integrated into clinical workflows.

RESULTS

SVM area under the ROC curve (AUC) for COG tube 1/2 radar plots improved from 0.949/0.921 to 0.989/0.968 after optimization. Performance was superior to PCA plots and comparable to UMAP, but with better generalizability to new data. When integrated into an MRD workflow, optimized radar plots distinguished B-lymphoblasts from other CD19-positive populations. MRD quantified by radar plots and serial gating were strongly correlated.

DISCUSSION

Radar plots were successfully optimized to discriminate between diverse B-lymphoblast populations and non-malignant CD19-positive populations in B-ALL MRD analysis. Our novel radar plot optimization strategy could be adapted to other MRD panels and clinical scenarios.

Malignancy-associated haemophagocytic lymphohistiocytosis

Haemophagocytic lymphohistiocytosis (HLH) is an inflammatory syndrome that can occur with cancer (malignancy-associated HLH) or with immune-activating therapies for cancer. Patients with lymphoma appear to be at particularly high risk for malignancy-associated HLH. The familial form of HLH is characterised by uncontrolled activation of macrophages and cytotoxic T cells, which can be identified by genetics or specific immune markers. However, the pathophysiology of malignancy-associated HLH is not well understood, and distinguishing pathological immune activation from the laboratory and clinical abnormalities seen in cancer and cancer treatment is challenging. Emerging diagnostic tools, such as serum cytokine or chemokine concentrations, flow cytometry, and other functional measures, are discussed. Mortality remains high with current approaches. Targeted therapy, including blockade of specific cytokines such as IL-1, IL-6, and IFNγ, and inhibition of the JAK-STAT pathways might improve outcomes for some patients. Finally, we discuss a framework for thinking of malignancy-associated HLH within a larger umbrella concept of cytokine storm syndrome.

Iodine Mineral Status of Etawah Crossbred Goat at Different Physiological Stages Fed Elephant Grass and Tofu Byproduct

Abstract. The objective of the study was to determine the iodine status and to map the thyroxin hormone concentration in etawah crossbred goat (ECG) at different physiological stages and its interrelation to the nutrition and performance. Fifteen female ECG was allotted in three physiolgical stage groups:  female kid, young female goat and lactating goat, fed elephant grass and tofu byproduct. The study was conducted  in Tossa Shakti Agro Company (TSA), Central Java, Indonesia. Analysis of variance in completely randomized design was used to determine the effect of physiological stages on soil and feed iodine content, blood serum thyroxin hormone concentration, nutrient and feed dry matter consumption, average daily gain and milk production. Result showed that soil iodine content was adequate to stimulate plant growth (3.109 mg/kg). Consumed feed iodine content  was adequate to all physiological stages, female kid, young female and lactating goat (1.003; 0.940 and 0.820 mg/kg, respectively). Thyroxin hormone concentration in blood serum of female kid and young female goat was  in normal range (8.23 and 10.05 µg/dl) but the concentration of thyroxin hormone in blood serum of lactating goat was  marginal ( 6.17 µg/dl).  Iodine supplementation was required for  lactating etawa crossbred goat  if tofu byproduct was included in its ration.Key words : nutrient, iodine, thyroxin hormone, etawah crossbred goat Abstrak.  Penelitian ini bertujuan mengkaji status iodine dan memetakan konsentrasi hormone tiroksin kambing peranakan etawah (PE) pada berbagai status fisiologis dan interelasinya dengan status nutrisi serta performans ternak.  Sebanyak 15 ekor kambing PE betina digunakan dalam penelitian yang terbagi atas tiga kelompok status fisiologis, yakni: cempe betina, kambing dara dan kambing laktasi.  Sebagai pakan, digunakan rumput gajah dan ampas tahu.  Penelitian ini dilakukan di PT. Tossa Shakti Agro (TSA) Kendal, Jawa Tengah.  Variabel yang diukur meliputi kandungan iodin tanah dan pakan, kadar hormon tiroksin serum darah, konsumsi bahan kering pakan dan nutrien, pertambahan bobot badan serta produksi susu. Data yang terkumpul diolah secara statistik dengan analisis variansi dalam rancangan acak lengkap guna mengetahui pengaruh status fisiologis terhadap variable-variabel tersebut.  Hasil penelitian menunjukkan bahwa kandungan iodine tanah memadai untuk menstimulasi pertumbuhan tanaman (3,109 mg/kg).  Kandungn iodin pakan terkonsumsi memadai untuk semua status fisiologis, dalam hal ini cempe betina, kambing dara dan kambing laktasi (masing-masing: 1,003; 0,940 dan 0,820 mg/kg).  Konsentrasi hormon tiroksin serum darah cempe betina dan kambing dara dalam kisaran normal (8,23 dan 10,05 ug/dl), tetapi konsentrasi hormon tiroksin serum darah kambing laktasi berada pada batas normal (borderline), yakni 6,17 ug/dl.  Suplementasi iodin diperlukan bagi kambing peranakan etawa yang sedang laktasi, jika ampas tahu digunakan sebagai bagian dari ransum.Kata kunci:  nutrien, iodin, hormone , kambing peranakan etawah

Notch initiates the endothelial-to-mesenchymal transition in the atrioventricular canal through autocrine activation of soluble guanylyl cyclase

The heart is the most common site of congenital defects, and valvuloseptal defects are the most common of the cardiac anomalies seen in the newborn. The process of endothelial-to-mesenchymal transition (EndMT) in the cardiac cushions is a required step during early valve development, and Notch signaling is required for this process. Here we show that Notch activation induces the transcription of both subunits of the soluble guanylyl cyclase (sGC) heterodimer, GUCY1A3 and GUCY1B3, which form the nitric oxide receptor. In parallel, Notch also promotes nitric oxide (NO) production by inducing Activin A, thereby activating a PI3-kinase/Akt pathway to phosphorylate eNOS. We thus show that the activation of sGC by NO through a Notch-dependent autocrine loop is necessary to drive early EndMT in the developing atrioventricular canal (AVC).

Differential regulation of transforming growth factor beta signaling pathways by Notch in human endothelial cells

Notch and transforming growth factor beta (TGFbeta) play critical roles in endothelial-to-mesenchymal transition (EndMT), a process that is essential for heart development. Previously, we have shown that Notch and TGFbeta signaling synergistically induce Snail expression in endothelial cells, which is required for EndMT in cardiac cushion morphogenesis. Here, we report that Notch activation modulates TGFbeta signaling pathways in a receptor-activated Smad (R-Smad)-specific manner. Notch activation inhibits TGFbeta/Smad1 and TGFbeta/Smad2 signaling pathways by decreasing the expression of Smad1 and Smad2 and their target genes. In contrast, Notch increases SMAD3 mRNA expression and protein half-life and regulates the expression of TGFbeta/Smad3 target genes in a gene-specific manner. Inhibition of Notch in the cardiac cushion of mouse embryonic hearts reduces Smad3 expression. Notch and TGFbeta synergistically up-regulate a subset of genes by recruiting Smad3 to both Smad and CSL binding sites and cooperatively inducing histone H4 acetylation. This is the first evidence that Notch activation affects R-Smad expression and that cooperative induction of histone acetylation at specific promoters underlies the selective synergy between Notch and TGFbeta signaling pathways.