Systems Biology

Rare predicted loss-of-function variants of type I IFN immunity genes are associated with life-threatening COVID-19

Wed, 2023-04-05 06:00

Genome Med. 2023 Apr 5;15(1):22. doi: 10.1186/s13073-023-01173-8.

ABSTRACT

BACKGROUND: We previously reported that impaired type I IFN activity, due to inborn errors of TLR3- and TLR7-dependent type I interferon (IFN) immunity or to autoantibodies against type I IFN, account for 15-20% of cases of life-threatening COVID-19 in unvaccinated patients. Therefore, the determinants of life-threatening COVID-19 remain to be identified in ~ 80% of cases.

METHODS: We report here a genome-wide rare variant burden association analysis in 3269 unvaccinated patients with life-threatening COVID-19, and 1373 unvaccinated SARS-CoV-2-infected individuals without pneumonia. Among the 928 patients tested for autoantibodies against type I IFN, a quarter (234) were positive and were excluded.

RESULTS: No gene reached genome-wide significance. Under a recessive model, the most significant gene with at-risk variants was TLR7, with an OR of 27.68 (95%CI 1.5-528.7, P = 1.1 × 10-4) for biochemically loss-of-function (bLOF) variants. We replicated the enrichment in rare predicted LOF (pLOF) variants at 13 influenza susceptibility loci involved in TLR3-dependent type I IFN immunity (OR = 3.70[95%CI 1.3-8.2], P = 2.1 × 10-4). This enrichment was further strengthened by (1) adding the recently reported TYK2 and TLR7 COVID-19 loci, particularly under a recessive model (OR = 19.65[95%CI 2.1-2635.4], P = 3.4 × 10-3), and (2) considering as pLOF branchpoint variants with potentially strong impacts on splicing among the 15 loci (OR = 4.40[9%CI 2.3-8.4], P = 7.7 × 10-8). Finally, the patients with pLOF/bLOF variants at these 15 loci were significantly younger (mean age [SD] = 43.3 [20.3] years) than the other patients (56.0 [17.3] years; P = 1.68 × 10-5).

CONCLUSIONS: Rare variants of TLR3- and TLR7-dependent type I IFN immunity genes can underlie life-threatening COVID-19, particularly with recessive inheritance, in patients under 60 years old.

PMID:37020259 | DOI:10.1186/s13073-023-01173-8

Categories: Literature Watch

Aldose reductase inhibition decelerates optic nerve degeneration by alleviating retinal microglia activation

Wed, 2023-04-05 06:00

Sci Rep. 2023 Apr 5;13(1):5592. doi: 10.1038/s41598-023-32702-5.

ABSTRACT

As part of the central nervous system (CNS), retinal ganglion cells (RGCs) and their axons are the only neurons in the retina that transmit visual signals from the eye to the brain via the optic nerve (ON). Unfortunately, they do not regenerate upon injury in mammals. In ON trauma, retinal microglia (RMG) become activated, inducing inflammatory responses and resulting in axon degeneration and RGC loss. Since aldose reductase (AR) is an inflammatory response mediator highly expressed in RMG, we investigated if pharmacological inhibition of AR can attenuate ocular inflammation and thereby promote RGC survival and axon regeneration after ON crush (ONC). In vitro, we discovered that Sorbinil, an AR inhibitor, attenuates BV2 microglia activation and migration in the lipopolysaccharide (LPS) and monocyte chemoattractant protein-1 (MCP-1) treatments. In vivo, Sorbinil suppressed ONC-induced Iba1 + microglia/macrophage infiltration in the retina and ON and promoted RGC survival. Moreover, Sorbinil restored RGC function and delayed axon degeneration one week after ONC. RNA sequencing data revealed that Sorbinil protects the retina from ONC-induced degeneration by suppressing inflammatory signaling. In summary, we report the first study demonstrating that AR inhibition transiently protects RGC and axon from degeneration, providing a potential therapeutic strategy for optic neuropathies.

PMID:37019993 | DOI:10.1038/s41598-023-32702-5

Categories: Literature Watch

Selection and adaptive introgression guided the complex evolutionary history of the European common bean

Wed, 2023-04-05 06:00

Nat Commun. 2023 Apr 5;14(1):1908. doi: 10.1038/s41467-023-37332-z.

ABSTRACT

Domesticated crops have been disseminated by humans over vast geographic areas. Common bean (Phaseolus vulgaris L.) was introduced in Europe after 1492. Here, by combining whole-genome profiling, metabolic fingerprinting and phenotypic characterisation, we show that the first common bean cultigens successfully introduced into Europe were of Andean origin, after Francisco Pizarro's expedition to northern Peru in 1529. We reveal that hybridisation, selection and recombination have shaped the genomic diversity of the European common bean in parallel with political constraints. There is clear evidence of adaptive introgression into the Mesoamerican-derived European genotypes, with 44 Andean introgressed genomic segments shared by more than 90% of European accessions and distributed across all chromosomes except PvChr11. Genomic scans for signatures of selection highlight the role of genes relevant to flowering and environmental adaptation, suggesting that introgression has been crucial for the dissemination of this tropical crop to the temperate regions of Europe.

PMID:37019898 | DOI:10.1038/s41467-023-37332-z

Categories: Literature Watch

Hematopoietic stem-cell gene therapy is associated with restored white matter microvascular function in cerebral adrenoleukodystrophy

Wed, 2023-04-05 06:00

Nat Commun. 2023 Apr 5;14(1):1900. doi: 10.1038/s41467-023-37262-w.

ABSTRACT

Blood-brain barrier disruption marks the onset of cerebral adrenoleukodystrophy (CALD), a devastating cerebral demyelinating disease caused by loss of ABCD1 gene function. The underlying mechanism are not well understood, but evidence suggests that microvascular dysfunction is involved. We analyzed cerebral perfusion imaging in boys with CALD treated with autologous hematopoietic stem-cells transduced with the Lenti-D lentiviral vector that contains ABCD1 cDNA as part of a single group, open-label phase 2-3 safety and efficacy study (NCT01896102) and patients treated with allogeneic hematopoietic stem cell transplantation. We found widespread and sustained normalization of white matter permeability and microvascular flow. We demonstrate that ABCD1 functional bone marrow-derived cells can engraft in the cerebral vascular and perivascular space. Inverse correlation between gene dosage and lesion growth suggests that corrected cells contribute long-term to remodeling of brain microvascular function. Further studies are needed to explore the longevity of these effects.

PMID:37019892 | DOI:10.1038/s41467-023-37262-w

Categories: Literature Watch

CAMSAP3 negatively regulates lung cancer cell invasion and angiogenesis through nucleolin/HIF-1α mRNA complex stabilization

Wed, 2023-04-05 06:00

Life Sci. 2023 Apr 3:121655. doi: 10.1016/j.lfs.2023.121655. Online ahead of print.

ABSTRACT

AIMS: Cancer metastasis is a major cause of lung cancer-related mortality, so identification of related molecular mechanisms is of interest. Calmodulin-regulated spectrin-associated protein 3 (CAMSAP3) has been implicated in lung cancer malignancies; however, its role in metastatic processes, including invasion and angiogenesis, is largely unknown.

MAIN METHOD: The clinical relevance of CAMSAP3 expression in lung cancer was evaluated. The relevance of CAMSAP3 expression to in vitro cell invasion and angiogenesis was assessed in human lung cancer cells and endothelial cells, respectively. The molecular mechanism was identified by qRT-PCR, immunoprecipitation, mass spectrometry, and RNA immunoprecipitation. The in vivo metastatic and angiogenic activities of lung cancer cells were assessed.

KEY FINDINGS: Low CAMSAP3 expression was found in malignant lung tissues and strongly correlated with a poor prognosis in lung adenocarcinoma (LUAD). CAMSAP3-knockout NSCLC exhibited high invasive ability, and CAMSAP3 knockout induced HUVEC proliferation and tube formation; these effects were significantly attenuated by reintroduction of exogenous wild-type CAMSAP3. Mechanistically, in the absence of CAMSAP3, the expression of hypoxia-inducible factor-1α (HIF-1α) was upregulated, which increased the levels of downstream HIF-1α targets such as vascular endothelial growth factor A (VEGFA) and matrix metalloproteinases (MMPs) 2 and 9. Proteomic analysis revealed that nucleolin (NCL) bound to CAMSAP3 to regulate HIF-1α mRNA stabilization. In addition, CAMSAP3-knockout lung cancer cells displayed highly aggressive behavior in metastasis and angiogenesis in vivo.

SIGNIFICANCE: This study reveals that CAMSAP3 plays a negative regulatory role in lung cancer cell metastatic behavior both in vitro and in vivo through NCL/HIF-1α mRNA complex stabilization.

PMID:37019300 | DOI:10.1016/j.lfs.2023.121655

Categories: Literature Watch

Identification of key differentially expressed genes in SARS-CoV-2 using RNA-seq analysis with a systems biology approach

Wed, 2023-04-05 06:00

Cytokine. 2023 Mar 24;166:156187. doi: 10.1016/j.cyto.2023.156187. Online ahead of print.

ABSTRACT

COVID-19 is associated with dysregulation of several genes and signaling pathways. Based on the importance of expression profiling in identification of the pathogenesis of COVID-19 and proposing novel therapies for this disorder, we have employed an in silico approach to find differentially expressed genes between COVID-19 patients and healthy controls and their relevance with cellular functions and signaling pathways. We obtained 630 DEmRNAs, including 486 down-regulated DEGs (such as CCL3 and RSAD2) and 144 up-regulated DEGs (such as RHO and IQCA1L), and 15 DElncRNAs, including 9 down-regulated DElncRNAs (such as PELATON and LINC01506) and 6 up-regulated DElncRNAs (such as AJUBA-DT and FALEC). The PPI network of DEGs showed the presence of a number immune-related genes such as those coding for HLA molecules and interferon regulatory factors. Taken together, these results highlight the importance of immune-related genes and pathways in the pathogenesis of COVID-19 and suggest novel targets for treatment of this disorder.

PMID:37018908 | DOI:10.1016/j.cyto.2023.156187

Categories: Literature Watch

Rewiring of miRNA-mRNA bipartite co-expression network as a novel way to understand the prostate cancer related players

Wed, 2023-04-05 06:00

Syst Biol Reprod Med. 2023 Apr 5:1-12. doi: 10.1080/19396368.2023.2187268. Online ahead of print.

ABSTRACT

The differential expression and direct targeting of mRNA by miRNA are two main logics of the traditional approach to constructing the miRNA-mRNA network. This approach, could be led to the loss of considerable information and some challenges of direct targeting. To avoid these problems, we analyzed the rewiring network and constructed two miRNA-mRNA expression bipartite networks for both normal and primary prostate cancer tissue obtained from PRAD-TCGA. We then calculated beta-coefficient of the regression-model when miR was dependent and mRNA independent for each miR and mRNA and separately in both networks. We defined the rewired edges as a significant change in the regression coefficient between normal and cancer states. The rewired nodes through multinomial distribution were defined and network from rewired edges and nodes was analyzed and enriched. Of the 306 rewired edges, 112(37%) were new, 123(40%) were lost, 44(14%) were strengthened, and 27(9%) weakened connections were discovered. The highest centrality of 106 rewired mRNAs belonged to PGM5, BOD1L1, C1S, SEPG, TMEFF2, and CSNK2A1. The highest centrality of 68 rewired miRs belonged to miR-181d, miR-4677, miR-4662a, miR-9.3, and miR-1301. SMAD and beta-catenin binding were enriched as molecular functions. The regulation was a frequently repeated concept in the biological process. Our rewiring analysis highlighted the impact of β-catenin and SMAD signaling as also some transcript factors like TGFB1I1 in prostate cancer progression. Altogether, we developed a miRNA-mRNA co-expression bipartite network to identify the hidden aspects of the prostate cancer mechanism, which traditional analysis -like differential expression- was not detect it.

PMID:37018429 | DOI:10.1080/19396368.2023.2187268

Categories: Literature Watch

The E2 glycoprotein holds key residues for Mayaro virus adaptation to the urban Aedes aegypti mosquito

Wed, 2023-04-05 06:00

PLoS Pathog. 2023 Apr 5;19(4):e1010491. doi: 10.1371/journal.ppat.1010491. Online ahead of print.

ABSTRACT

Adaptation to mosquito vectors suited for transmission in urban settings is a major driver in the emergence of arboviruses. To better anticipate future emergence events, it is crucial to assess their potential to adapt to new vector hosts. In this work, we used two different experimental evolution approaches to study the adaptation process of an emerging alphavirus, Mayaro virus (MAYV), to Ae. aegypti, an urban mosquito vector of many other arboviruses. We identified E2-T179N as a key mutation increasing MAYV replication in insect cells and enhancing transmission after escaping the midgut of live Ae. aegypti. In contrast, this mutation decreased viral replication and binding in human fibroblasts, a primary cellular target of MAYV in humans. We also showed that MAYV E2-T179N generates reduced viremia and displays less severe tissue pathology in vivo in a mouse model. We found evidence in mouse fibroblasts that MAYV E2-T179N is less dependent on the Mxra8 receptor for replication than WT MAYV. Similarly, exogenous expression of human apolipoprotein receptor 2 and Mxra8 enhanced WT MAYV replication compared to MAYV E2-T179N. When this mutation was introduced in the closely related chikungunya virus, which has caused major outbreaks globally in the past two decades, we observed increased replication in both human and insect cells, suggesting E2 position 179 is an important determinant of alphavirus host-adaptation, although in a virus-specific manner. Collectively, these results indicate that adaptation at the T179 residue in MAYV E2 may result in increased vector competence-but coming at the cost of optimal replication in humans-and may represent a first step towards a future emergence event.

PMID:37018377 | DOI:10.1371/journal.ppat.1010491

Categories: Literature Watch

Correction: Bayesian parameter estimation for dynamical models in systems biology

Wed, 2023-04-05 06:00

PLoS Comput Biol. 2023 Apr 5;19(4):e1011041. doi: 10.1371/journal.pcbi.1011041. eCollection 2023 Apr.

ABSTRACT

[This corrects the article DOI: 10.1371/journal.pcbi.1010651.].

PMID:37018170 | DOI:10.1371/journal.pcbi.1011041

Categories: Literature Watch

Nodal coordinates the anterior-posterior patterning of germ layers and induces head formation in zebrafish explants

Wed, 2023-04-05 06:00

Cell Rep. 2023 Apr 4;42(4):112351. doi: 10.1016/j.celrep.2023.112351. Online ahead of print.

ABSTRACT

Much progress has been made toward generating analogs of early embryos, such as gastruloids and embryoids, in vitro. However, methods for how to fully mimic the cell movements of gastrulation and coordinate germ-layer patterning to induce head formation are still lacking. Here, we show that a regional Nodal gradient applied to zebrafish animal pole explant can generate a structure that recapitulates the key cell movements of gastrulation. Using single-cell transcriptome and in situ hybridization analysis, we assess the dynamics of the cell fates and patterning of this structure. The mesendoderm differentiates into the anterior endoderm, prechordal plate, notochord, and tailbud-like cells along an anterior-posterior axis, and an anterior-posterior-patterned head-like structure (HLS) progressively forms during late gastrulation. Among 105 immediate Nodal targets, 14 genes contain axis-induction ability, and 5 of them induce a complete or partial head structure when overexpressed in the ventral side of zebrafish embryos.

PMID:37018074 | DOI:10.1016/j.celrep.2023.112351

Categories: Literature Watch

Light-Deactivated Fluorescent Probes (FLASH-Off) for Multiplexed Imaging

Wed, 2023-04-05 06:00

J Am Chem Soc. 2023 Apr 5. doi: 10.1021/jacs.3c00170. Online ahead of print.

ABSTRACT

Highly multiplexed, cyclic fluorescence imaging has advanced our understanding of the biology, evolution, and complexity of human diseases. Currently available cyclic methods still have considerable limitations including the need for long quenching times and extensive wash steps. Here, we report a new series of fluorochromes that can be efficiently inactivated by a single light pulse (∼405 nm) by means of a photo-immolating triazene linker. Upon UV-light irradiation, the rhodamines are cleaved off from the antibody conjugates and undergo a fast intramolecular spirocyclization that inherently switches off their fluorescence emission without the need to wash or add exogenous chemicals. We show that these switch-off probes are fast, highly controllable, biocompatible, and allow spatiotemporal quenching control of live and fixed samples.

PMID:37018018 | DOI:10.1021/jacs.3c00170

Categories: Literature Watch

Bias in nutrition-health associations is not eliminated by excluding extreme reporters in empirical or simulation studies

Wed, 2023-04-05 06:00

Elife. 2023 Apr 5;12:e83616. doi: 10.7554/eLife.83616.

ABSTRACT

Self-reported nutrition intake (NI) data are prone to reporting bias that may induce bias in estimands in nutrition studies; however, they are used anyway due to high feasibility. We examined whether applying Goldberg cutoffs to remove 'implausible' self-reported NI could reliably reduce bias compared to biomarkers for energy, sodium, potassium, and protein. Using the Interactive Diet and Activity Tracking in the American Association of Retired Persons (IDATA) data, significant bias in mean NI was removed with Goldberg cutoffs (120 among 303 participants excluded). Associations between NI and health outcomes (weight, waist circumference, heart rate, systolic/diastolic blood pressure, and VO2 max) were estimated, but sample size was insufficient to evaluate bias reductions. We therefore simulated data based on IDATA. Significant bias in simulated associations using self-reported NI was reduced but not completely eliminated by Goldberg cutoffs in 14 of 24 nutrition-outcome pairs; bias was not reduced for the remaining 10 cases. Also, 95% coverage probabilities were improved by applying Goldberg cutoffs in most cases but underperformed compared with biomarker data. Although Goldberg cutoffs may achieve bias elimination in estimating mean NI, bias in estimates of associations between NI and outcomes will not necessarily be reduced or eliminated after application of Goldberg cutoffs. Whether one uses Goldberg cutoffs should therefore be decided based on research purposes and not general rules.

PMID:37017635 | DOI:10.7554/eLife.83616

Categories: Literature Watch

Cytochalasans produced by <em>Xylaria karyophthora</em> and their biological activities

Wed, 2023-04-05 06:00

Mycologia. 2023 Apr 5:1-11. doi: 10.1080/00275514.2023.2188868. Online ahead of print.

ABSTRACT

The recent description of the putative fungal pathogen of greenheart trees, Xylaria karyophthora (Xylariaceae, Ascomycota), prompted a study of its secondary metabolism to access its ability to produce cytochalasans in culture. Solid-state fermentation of the ex-type strain on rice medium resulted in the isolation of a series of 19,20-epoxidated cytochalasins by means of preparative high-performance liquid chromatography (HPLC). Nine out of 10 compounds could be assigned to previously described structures, with one compound being new to science after structural assignment via nuclear magnetic resonance (NMR) assisted by high-resolution mass spectrometry (HRMS). We propose the trivial name "karyochalasin" for the unprecedented metabolite. The compounds were used in our ongoing screening campaign to study the structure-activity relationship of this family of compounds. This was done by examining their cytotoxicity against eukaryotic cells and impact on the organization of networks built by their main target, actin-a protein indispensable for processes mediating cellular shape changes and movement. Moreover, the cytochalasins' ability to inhibit the biofilm formation of Candida albicans and Staphylococcus aureus was examined.

PMID:37017575 | DOI:10.1080/00275514.2023.2188868

Categories: Literature Watch

Effects of a ketogenic and low-fat diet on the human metabolome, microbiome, and foodome in adults at risk for Alzheimer's disease

Wed, 2023-04-05 06:00

Alzheimers Dement. 2023 Apr 5. doi: 10.1002/alz.13007. Online ahead of print.

ABSTRACT

INTRODUCTION: The ketogenic diet (KD) is an intriguing therapeutic candidate for Alzheimer's disease (AD) given its protective effects against metabolic dysregulation and seizures. Gut microbiota are essential for KD-mediated neuroprotection against seizures as well as modulation of bile acids, which play a major role in cholesterol metabolism. These relationships motivated our analysis of gut microbiota and metabolites related to cognitive status following a controlled KD intervention compared with a low-fat-diet intervention.

METHODS: Prediabetic adults, either with mild cognitive impairment (MCI) or cognitively normal (CN), were placed on either a low-fat American Heart Association diet or high-fat modified Mediterranean KD (MMKD) for 6 weeks; then, after a 6-week washout period, they crossed over to the alternate diet. We collected stool samples for shotgun metagenomics and untargeted metabolomics at five time points to investigate individuals' microbiome and metabolome throughout the dietary interventions.

RESULTS: Participants with MCI on the MMKD had lower levels of GABA-producing microbes Alistipes sp. CAG:514 and GABA, and higher levels of GABA-regulating microbes Akkermansia muciniphila. MCI individuals with curcumin in their diet had lower levels of bile salt hydrolase-containing microbes and an altered bile acid pool, suggesting reduced gut motility.

DISCUSSION: Our results suggest that the MMKD may benefit adults with MCI through modulation of GABA levels and gut-transit time.

PMID:37017243 | DOI:10.1002/alz.13007

Categories: Literature Watch

Temporal tracking of microglial and monocyte single-cell transcriptomics in lethal flavivirus infection

Tue, 2023-04-04 06:00

Acta Neuropathol Commun. 2023 Apr 4;11(1):60. doi: 10.1186/s40478-023-01547-4.

ABSTRACT

As the resident parenchymal myeloid population in the central nervous system (CNS), microglia are strategically positioned to respond to neurotropic virus invasion and have been implicated in promoting both disease resolution and progression in the acute and post-infectious phase of virus encephalitis. In a mouse model of West Nile virus encephalitis (WNE), infection of the CNS results in recruitment of large numbers of peripheral immune cells into the brain, the majority being nitric oxide (NO)-producing Ly6Chi inflammatory monocyte-derived cells (MCs). In this model, these cells enhance immunopathology and mortality. However, the contribution of microglia to this response is currently undefined. Here we used a combination of experimental tools, including single-cell RNA sequencing (scRNA-seq), microglia and MC depletion reagents, high-dimensional spectral cytometry and computational algorithms to dissect the differential contribution of microglia and MCs to the anti-viral immune response in severe neuroinflammation seen in WNE. Intriguingly, analysis of scRNA-seq data revealed 6 unique microglia and 3 unique MC clusters that were predominantly timepoint-specific, demonstrating substantial transcriptional adaptation with disease progression over the course of WNE. While microglia and MC adopted unique gene expression profiles, gene ontology enrichment analysis, coupled with microglia and MC depletion studies, demonstrated a role for both of these cells in the trafficking of peripheral immune cells into the CNS, T cell responses and viral clearance. Over the course of infection, microglia transitioned from a homeostatic to an anti-viral and then into an immune cell-recruiting phenotype. Conversely, MC adopted antigen-presenting, immune cell-recruiting and NO-producing phenotypes, which all had anti-viral function. Overall, this study defines for the first time the single-cell transcriptomic responses of microglia and MCs over the course of WNE, demonstrating both protective and pathological roles of these cells that could potentially be targeted for differential therapeutic intervention to dampen immune-mediated pathology, while maintaining viral clearance functions.

PMID:37016414 | DOI:10.1186/s40478-023-01547-4

Categories: Literature Watch

Comprehensive proteomics and platform validation of urinary biomarkers for bladder cancer diagnosis and staging

Tue, 2023-04-04 06:00

BMC Med. 2023 Apr 5;21(1):133. doi: 10.1186/s12916-023-02813-x.

ABSTRACT

BACKGROUND: Bladder cancer (BC) is among the most common cancers diagnosed in men in the USA. The current gold standards for the diagnosis of BC are invasive or lack the sensitivity to correctly identify the disease.

METHODS: An aptamer-based screen analyzed the expression of 1317 proteins in BC compared to urology clinic controls. The top hits were subjected to systems biology analyses. Next, 30 urine proteins were ELISA-validated in an independent cohort of 68 subjects. Three of these proteins were next validated in an independent BC cohort of differing ethnicity.

RESULTS: Systems biology analysis implicated molecular functions related to the extracellular matrix, collagen, integrin, heparin, and transmembrane tyrosine kinase signaling in BC susceptibility, with HNF4A and NFKB1 emerging as key molecular regulators. STEM analysis of the dysregulated pathways implicated a functional role for the immune system, complement, and interleukins in BC disease progression. Of 21 urine proteins that discriminated BC from urology clinic controls (UC), urine D-dimer displayed the highest accuracy (0.96) and sensitivity of 97%. Furthermore, 8 urine proteins significantly discriminated MIBC from NMIBC (AUC = 0.75-0.99), with IL-8 and IgA being the best performers. Urine IgA and fibronectin exhibited the highest specificity of 80% at fixed sensitivity for identifying advanced BC.

CONCLUSIONS: Given the high sensitivity (97%) of urine D-dimer for BC, it may have a role in the initial diagnosis or detection of cancer recurrence. On the other hand, urine IL-8 and IgA may have the potential in identifying disease progression during patient follow-up. The use of these biomarkers for initial triage could have a significant impact as the current cystoscopy-based diagnostic and surveillance approach is costly and invasive when compared to a simple urine test.

PMID:37016361 | DOI:10.1186/s12916-023-02813-x

Categories: Literature Watch

Kernelized multiview signed graph learning for single-cell RNA sequencing data

Tue, 2023-04-04 06:00

BMC Bioinformatics. 2023 Apr 4;24(1):127. doi: 10.1186/s12859-023-05250-y.

ABSTRACT

BACKGROUND: Characterizing the topology of gene regulatory networks (GRNs) is a fundamental problem in systems biology. The advent of single cell technologies has made it possible to construct GRNs at finer resolutions than bulk and microarray datasets. However, cellular heterogeneity and sparsity of the single cell datasets render void the application of regular Gaussian assumptions for constructing GRNs. Additionally, most GRN reconstruction approaches estimate a single network for the entire data. This could cause potential loss of information when single cell datasets are generated from multiple treatment conditions/disease states.

RESULTS: To better characterize single cell GRNs under different but related conditions, we propose the joint estimation of multiple networks using multiple signed graph learning (scMSGL). The proposed method is based on recently developed graph signal processing (GSP) based graph learning, where GRNs and gene expressions are modeled as signed graphs and graph signals, respectively. scMSGL learns multiple GRNs by optimizing the total variation of gene expressions with respect to GRNs while ensuring that the learned GRNs are similar to each other through regularization with respect to a learned signed consensus graph. We further kernelize scMSGL with the kernel selected to suit the structure of single cell data.

CONCLUSIONS: scMSGL is shown to have superior performance over existing state of the art methods in GRN recovery on simulated datasets. Furthermore, scMSGL successfully identifies well-established regulators in a mouse embryonic stem cell differentiation study and a cancer clinical study of medulloblastoma.

PMID:37016281 | DOI:10.1186/s12859-023-05250-y

Categories: Literature Watch

Pregnancy-specific responses to COVID-19 revealed by high-throughput proteomics of human plasma

Tue, 2023-04-04 06:00

Commun Med (Lond). 2023 Apr 4;3(1):48. doi: 10.1038/s43856-023-00268-y.

ABSTRACT

BACKGROUND: Pregnant women are at greater risk of adverse outcomes, including mortality, as well as obstetrical complications resulting from COVID-19. However, pregnancy-specific changes that underlie such worsened outcomes remain unclear.

METHODS: Plasma samples were collected from pregnant women and non-pregnant individuals (male and female) with (n = 72 pregnant, 52 non-pregnant) and without (n = 29 pregnant, 41 non-pregnant) COVID-19. COVID-19 patients were grouped as asymptomatic, mild, moderate, severe, or critically ill according to NIH classifications. Proteomic profiling of 7,288 analytes corresponding to 6,596 unique protein targets was performed using the SOMAmer platform.

RESULTS: Herein, we profile the plasma proteome of pregnant and non-pregnant COVID-19 patients and controls and show alterations that display a dose-response relationship with disease severity; yet, such proteomic perturbations are dampened during pregnancy. In both pregnant and non-pregnant state, the proteome response induced by COVID-19 shows enrichment of mediators implicated in cytokine storm, endothelial dysfunction, and angiogenesis. Shared and pregnancy-specific proteomic changes are identified: pregnant women display a tailored response that may protect the conceptus from heightened inflammation, while non-pregnant individuals display a stronger response to repel infection. Furthermore, the plasma proteome can accurately identify COVID-19 patients, even when asymptomatic or with mild symptoms.

CONCLUSION: This study represents the most comprehensive characterization of the plasma proteome of pregnant and non-pregnant COVID-19 patients. Our findings emphasize the distinct immune modulation between the non-pregnant and pregnant states, providing insight into the pathogenesis of COVID-19 as well as a potential explanation for the more severe outcomes observed in pregnant women.

PMID:37016066 | DOI:10.1038/s43856-023-00268-y

Categories: Literature Watch

Phylogenomic analysis uncovers a 9-year variation of Uganda influenza type-A strains from the WHO-recommended vaccines and other Africa strains

Tue, 2023-04-04 06:00

Sci Rep. 2023 Apr 4;13(1):5516. doi: 10.1038/s41598-023-30667-z.

ABSTRACT

Genetic characterisation of circulating influenza viruses directs annual vaccine strain selection and mitigation of infection spread. We used next-generation sequencing to locally generate whole genomes from 116 A(H1N1)pdm09 and 118 A(H3N2) positive patient swabs collected across Uganda between 2010 and 2018. We recovered sequences from 92% (215/234) of the swabs, 90% (193/215) of which were whole genomes. The newly-generated sequences were genetically and phylogenetically compared to the WHO-recommended vaccines and other Africa strains sampled since 1994. Uganda strain hemagglutinin (n = 206), neuraminidase (n = 207), and matrix protein (MP, n = 213) sequences had 95.23-99.65%, 95.31-99.79%, and 95.46-100% amino acid similarity to the 2010-2020 season vaccines, respectively, with several mutated hemagglutinin antigenic, receptor binding, and N-linked glycosylation sites. Uganda influenza type-A virus strains sequenced before 2016 clustered uniquely while later strains mixed with other Africa and global strains. We are the first to report novel A(H1N1)pdm09 subclades 6B.1A.3, 6B.1A.5(a,b), and 6B.1A.6 (± T120A) that circulated in Eastern, Western, and Southern Africa in 2017-2019. Africa forms part of the global influenza ecology with high viral genetic diversity, progressive antigenic drift, and local transmissions. For a continent with inadequate health resources and where social distancing is unsustainable, vaccination is the best option. Hence, African stakeholders should prioritise routine genome sequencing and analysis to direct vaccine selection and virus control.

PMID:37015946 | DOI:10.1038/s41598-023-30667-z

Categories: Literature Watch

ITK degradation to block T cell receptor signaling and overcome therapeutic resistance in T cell lymphomas

Tue, 2023-04-04 06:00

Cell Chem Biol. 2023 Mar 27:S2451-9456(23)00086-7. doi: 10.1016/j.chembiol.2023.03.007. Online ahead of print.

ABSTRACT

Interleukin (IL)-2-inducible T cell kinase (ITK) is essential for T cell receptor (TCR) signaling and plays an integral role in T cell proliferation and differentiation. Unlike the ITK homolog BTK, no inhibitors of ITK are currently US Food and Drug Administration (FDA) approved. In addition, recent studies have identified mutations within BTK that confer resistance to both covalent and non-covalent inhibitors. Here, as an alternative strategy, we report the development of BSJ-05-037, a potent and selective heterobifunctional degrader of ITK. BSJ-05-037 displayed enhanced anti-proliferative effects relative to its parent inhibitor BMS-509744, blocked the activation of NF-kB/GATA-3 signaling, and increased the sensitivity of T cell lymphoma cells to cytotoxic chemotherapy both in vitro and in vivo. In summary, targeted degradation of ITK is a novel approach to modulate TCR signal strength that could have broad application for the investigation and treatment of T cell-mediated diseases.

PMID:37015223 | DOI:10.1016/j.chembiol.2023.03.007

Categories: Literature Watch

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