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1.
Nature ; 628(8007): 365-372, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38509364

ABSTRACT

Although modern humans left Africa multiple times over 100,000 years ago, those broadly ancestral to non-Africans dispersed less than 100,000 years ago1. Most models hold that these events occurred through green corridors created during humid periods because arid intervals constrained population movements2. Here we report an archaeological site-Shinfa-Metema 1, in the lowlands of northwest Ethiopia, with Youngest Toba Tuff cryptotephra dated to around 74,000 years ago-that provides early and rare evidence of intensive riverine-based foraging aided by the likely adoption of the bow and arrow. The diet included a wide range of terrestrial and aquatic animals. Stable oxygen isotopes from fossil mammal teeth and ostrich eggshell show that the site was occupied during a period of high seasonal aridity. The unusual abundance of fish suggests that capture occurred in the ever smaller and shallower waterholes of a seasonal river during a long dry season, revealing flexible adaptations to challenging climatic conditions during the Middle Stone Age. Adaptive foraging along dry-season waterholes would have transformed seasonal rivers into 'blue highway' corridors, potentially facilitating an out-of-Africa dispersal and suggesting that the event was not restricted to times of humid climates. The behavioural flexibility required to survive seasonally arid conditions in general, and the apparent short-term effects of the Toba supereruption in particular were probably key to the most recent dispersal and subsequent worldwide expansion of modern humans.


Subject(s)
Climate , Human Migration , Animals , Humans , Archaeology , Ethiopia , Mammals , Seasons , Diet/history , History, Ancient , Human Migration/history , Fossils , Struthioniformes , Droughts , Fishes
2.
Sci Total Environ ; 917: 170398, 2024 Mar 20.
Article in English | MEDLINE | ID: mdl-38281636

ABSTRACT

Pinecone shells are assessed as a cost-effective biosorbent for the removal of metal ions Pb(II), Cu(II), Cd(II), Ni(II), and Cr(VI) in a fixed-bed column. Influent concentration, bed height, and flowrate are studied to improve efficiency. The breakthrough data is well fitted by the Sips adsorption model, suggesting a surface complexation mechanism, with maximum adsorption capacities of 11.1 mg/g for Cu(II) and 66 mg/g for Pb(II). In multimetal solutions, the uptake sequence at breakthrough and saturation is Pb(II) > Cu(II) > Cd(II). Characterization via FTIR and XRD reveals carboxyl and hydroxyl functional groups interacting with metal ions. Ca(II) does not compete with Pb(II), Cu(II), and Cd(II) adsorption, highlighting the ability of pinecone to adsorb heavy metals via surface complexation. Its application in the treatment of industrial effluents containing Cu(II), Ni(II), and Cr(VI) is explored. The study investigates bed media regeneration via eluting adsorbed metal ions with hydrochloric acid solutions. The potential of pinecone shells as an efficient biosorbent for removing toxic metal ions from industrial wastewater is emphasized. These findings enhance our understanding of the adsorption mechanism and underscore the fixed-bed column system's applicability in real-world scenarios, addressing environmental concerns related to heavy metal contamination of industrial effluents.

3.
J Immunol ; 210(11): 1700-1716, 2023 06 01.
Article in English | MEDLINE | ID: mdl-37093875

ABSTRACT

Th17 cells have been investigated in mice primarily for their contributions to autoimmune diseases. However, the pathways of differentiation of Th17 and related Th cells (type 17 cells) and the structure of the type 17 memory population in humans are not well understood; such understanding is critical for manipulating these cells in vivo. By exploiting differences in levels of surface CCR6, we found that human type 17 memory cells, including individual T cell clonotypes, form an elongated continuum of type 17 character along which cells can be driven by increasing RORγt. This continuum includes cells preserved within the memory pool with potentials that reflect the early preferential activation of multiple over single lineages. The phenotypes and epigenomes of CCR6+ cells are stable across cell divisions under noninflammatory conditions. Nonetheless, activation in polarizing and nonpolarizing conditions can yield additional functionalities, revealing, respectively, both environmentally induced and imprinted mechanisms that contribute differentially across the type 17 continuum to yield the unusual plasticity ascribed to type 17 cells.


Subject(s)
Autoimmune Diseases , Th17 Cells , Humans , Cell Differentiation , Phenotype , Receptors, CCR6/genetics , Th1 Cells/metabolism
4.
J Exp Med ; 220(8)2023 08 07.
Article in English | MEDLINE | ID: mdl-37097292

ABSTRACT

Control of Mycobacterium tuberculosis (Mtb) infection requires generation of T cells that migrate to granulomas, complex immune structures surrounding sites of bacterial replication. Here we compared the gene expression profiles of T cells in pulmonary granulomas, bronchoalveolar lavage, and blood of Mtb-infected rhesus macaques to identify granuloma-enriched T cell genes. TNFRSF8/CD30 was among the top genes upregulated in both CD4 and CD8 T cells from granulomas. In mice, CD30 expression on CD4 T cells is required for survival of Mtb infection, and there is no major role for CD30 in protection by other cell types. Transcriptomic comparison of WT and CD30-/- CD4 T cells from the lungs of Mtb-infected mixed bone marrow chimeric mice showed that CD30 directly promotes CD4 T cell differentiation and the expression of multiple effector molecules. These results demonstrate that the CD30 co-stimulatory axis is highly upregulated on granuloma T cells and is critical for protective T cell responses against Mtb infection.


Subject(s)
Mycobacterium tuberculosis , Tuberculosis , Animals , Mice , CD4-Positive T-Lymphocytes , Cell Differentiation , Granuloma/metabolism , Macaca mulatta , Tuberculosis/microbiology , Ki-1 Antigen/immunology
5.
bioRxiv ; 2023 Jan 06.
Article in English | MEDLINE | ID: mdl-36789418

ABSTRACT

Th17 cells have been investigated in mice primarily for their contributions to autoimmune diseases. However, the pathways of differentiation of Th17 and related (type 17) cells and the structure of the type 17 memory population in humans are not well understood; such understanding is critical for manipulating these cells in vivo . By exploiting differences in levels of surface CCR6, we found that human type 17 memory cells, including individual T cell clonotypes, form an elongated continuum of type 17 character along which cells can be driven by increasing RORγt. This continuum includes cells preserved within the memory pool with potentials that reflect the early preferential activation of multiple over single lineages. The CCR6 + cells' phenotypes and epigenomes are stable across cell divisions under homeostatic conditions. Nonetheless, activation in polarizing and non-polarizing conditions can yield additional functionalities, revealing, respectively, both environmentally induced and imprinted mechanisms that contribute differentially across the continuum to yield the unusual plasticity ascribed to type 17 cells.

6.
bioRxiv ; 2023 Feb 13.
Article in English | MEDLINE | ID: mdl-36789428

ABSTRACT

Pro-inflammatory T cells co-express multiple chemokine receptors, but the distinct functions of individual receptors on these cells are largely unknown. Human Th17 cells uniformly express the chemokine receptor CCR6, and we discovered that the subgroup of CD4+CCR6+ cells that co-express CCR2 possess a pathogenic Th17 signature, can produce inflammatory cytokines independent of TCR activation, and are unusually efficient at transendothelial migration (TEM). The ligand for CCR6, CCL20, was capable of binding to activated endothelial cells (ECs) and inducing firm arrest of CCR6+CCR2+ cells under conditions of flow - but CCR6 could not mediate TEM. By contrast, CCL2 and other ligands for CCR2, despite being secreted from both luminal and basal sides of ECs, failed to bind to the EC surfaces - and CCR2 could not mediate arrest. Nonetheless, CCR2 was required for TEM. To understand if CCR2's inability to mediate arrest was due solely to an absence of EC-bound ligands, we generated a CCL2-CXCL9 chimeric chemokine that could bind to the EC surface. Although display of CCL2 on the ECs did indeed lead to CCR2-mediated arrest of CCR6+CCR2+ cells, activating CCR2 with surface-bound CCL2 blocked TEM. We conclude that mediating arrest and TEM are mutually exclusive activities of chemokine receptors and/or their ligands that depend, respectively, on chemokines that bind to the EC luminal surfaces versus non-binding chemokines that form transendothelial gradients under conditions of flow. Our findings provide fundamental insights into mechanisms of lymphocyte extravasation and may lead to novel strategies to block or enhance their migration into tissue.

8.
Clin Cancer Res ; 29(2): 349-363, 2023 01 17.
Article in English | MEDLINE | ID: mdl-36099324

ABSTRACT

PURPOSE: Ovarian cancer is the most lethal gynecologic cancer and intrinsically resistant to checkpoint immunotherapies. We sought to augment innate immunity, building on previous work with IFNs and monocytes. PATIENTS AND METHODS: Preclinical experiments were designed to define the mechanisms of cancer cell death mediated by the combination of IFNs α and γ with monocytes. We translated these preclinical findings into a phase I trial of autologous IFN-activated monocytes administered intraperitoneally to platinum-resistant or -refractory ovarian cancer patients. RESULTS: IFN-treated monocytes induced caspase 8-dependent apoptosis by the proapoptotic TRAIL and mediated by the death receptors 4 and 5 (DR4 and DR5, respectively) on cancer cells. Therapy was well tolerated with evidence of clinical activity, as 2 of 9 evaluable patients had a partial response by RECIST criteria, and 1 additional patient had a CA-125 response. Upregulation of monocyte-produced TRAIL and cytokines was confirmed in peripheral blood. Long-term responders had alterations in innate and adaptive immune compartments. CONCLUSIONS: Given the mechanism of cancer cell death, and the acceptable tolerability of the clinical regimen, this platform presents a possibility for future combination therapies to augment anticancer immunity. See related commentary by Chow and Dorigo, p. 299.


Subject(s)
Monocytes , Ovarian Neoplasms , Humans , Female , Monocytes/metabolism , Apoptosis , Interferon-alpha/therapeutic use , Ovarian Neoplasms/drug therapy , Immunotherapy , TNF-Related Apoptosis-Inducing Ligand/metabolism , Receptors, TNF-Related Apoptosis-Inducing Ligand/metabolism
9.
Am J Hum Genet ; 109(12): 2210-2229, 2022 12 01.
Article in English | MEDLINE | ID: mdl-36423637

ABSTRACT

The most recent genome-wide association study (GWAS) of cutaneous melanoma identified 54 risk-associated loci, but functional variants and their target genes for most have not been established. Here, we performed massively parallel reporter assays (MPRAs) by using malignant melanoma and normal melanocyte cells and further integrated multi-layer annotation to systematically prioritize functional variants and susceptibility genes from these GWAS loci. Of 1,992 risk-associated variants tested in MPRAs, we identified 285 from 42 loci (78% of the known loci) displaying significant allelic transcriptional activities in either cell type (FDR < 1%). We further characterized MPRA-significant variants by motif prediction, epigenomic annotation, and statistical/functional fine-mapping to create integrative variant scores, which prioritized one to six plausible candidate variants per locus for the 42 loci and nominated a single variant for 43% of these loci. Overlaying the MPRA-significant variants with genome-wide significant expression or methylation quantitative trait loci (eQTLs or meQTLs, respectively) from melanocytes or melanomas identified candidate susceptibility genes for 60% of variants (172 of 285 variants). CRISPRi of top-scoring variants validated their cis-regulatory effect on the eQTL target genes, MAFF (22q13.1) and GPRC5A (12p13.1). Finally, we identified 36 melanoma-specific and 45 melanocyte-specific MPRA-significant variants, a subset of which are linked to cell-type-specific target genes. Analyses of transcription factor availability in MPRA datasets and variant-transcription-factor interaction in eQTL datasets highlighted the roles of transcription factors in cell-type-specific variant functionality. In conclusion, MPRAs along with variant scoring effectively prioritized plausible candidates for most melanoma GWAS loci and highlighted cellular contexts where the susceptibility variants are functional.


Subject(s)
Melanoma , Skin Neoplasms , Humans , Melanoma/genetics , Skin Neoplasms/genetics , Genome-Wide Association Study , Biological Assay , Transcription Factors , Receptors, G-Protein-Coupled , Melanoma, Cutaneous Malignant
10.
iScience ; 25(1): 103588, 2022 Jan 21.
Article in English | MEDLINE | ID: mdl-35005538

ABSTRACT

HIV-specific T cells have diminished effector function and fail to control/eliminate the virus. IL-27, a member of the IL-6/IL-12 cytokine superfamily has been shown to inhibit HIV replication. However, whether or not IL-27 can enhance HIV-specific T cell function is largely unknown. In the present manuscript, we investigated the role of IL-27 signaling in human T cells by evaluating the global transcriptional changes related to the function of HIV-specific T cells. We found that T cells from people living with HIV (PLWH), expressed higher levels of STAT1 leading to enhanced STAT1 activation upon IL-27 stimulation. Observed IL-27 induced transcriptional changes were associated with IFN/STAT1-dependent pathways in CD4 and CD8 T cells. Importantly, IL-27 dependent modulation of T-bet expression promoted IFNγ secretion by TIGIT+HIVGag-specific T cells. This new immunomodulatory effect of IL-27 on HIV-specific T cell function suggests its potential therapeutic use in cure strategies.

11.
J Med Chem ; 64(17): 12790-12807, 2021 09 09.
Article in English | MEDLINE | ID: mdl-34414766

ABSTRACT

Phenotypic whole cell high-throughput screening of a ∼150,000 diverse set of compounds against Mycobacterium tuberculosis (Mtb) in cholesterol-containing media identified 1,3-diarylpyrazolyl-acylsulfonamide 1 as a moderately active hit. Structure-activity relationship (SAR) studies demonstrated a clear scope to improve whole cell potency to MIC values of <0.5 µM, and a plausible pharmacophore model was developed to describe the chemical space of active compounds. Compounds are bactericidal in vitro against replicating Mtb and retained activity against multidrug-resistant clinical isolates. Initial biology triage assays indicated cell wall biosynthesis as a plausible mode-of-action for the series. However, no cross-resistance with known cell wall targets such as MmpL3, DprE1, InhA, and EthA was detected, suggesting a potentially novel mode-of-action or inhibition. The in vitro and in vivo drug metabolism and pharmacokinetics profiles of several active compounds from the series were established leading to the identification of a compound for in vivo efficacy proof-of-concept studies.


Subject(s)
Antitubercular Agents/pharmacology , Cell Wall/metabolism , Mycobacterium tuberculosis/drug effects , Sulfonamides/pharmacology , Antitubercular Agents/chemical synthesis , Antitubercular Agents/chemistry , Drug Discovery , Hep G2 Cells , Humans , Microbial Sensitivity Tests , Models, Molecular , Molecular Structure , Mycobacterium tuberculosis/metabolism , Structure-Activity Relationship , Sulfonamides/chemistry
12.
Am J Hum Genet ; 108(9): 1590-1610, 2021 09 02.
Article in English | MEDLINE | ID: mdl-34390653

ABSTRACT

Our study investigated the underlying mechanism for the 14q24 renal cell carcinoma (RCC) susceptibility risk locus identified by a genome-wide association study (GWAS). The sentinel single-nucleotide polymorphism (SNP), rs4903064, at 14q24 confers an allele-specific effect on expression of the double PHD fingers 3 (DPF3) of the BAF SWI/SNF complex as assessed by massively parallel reporter assay, confirmatory luciferase assays, and eQTL analyses. Overexpression of DPF3 in renal cell lines increases growth rates and alters chromatin accessibility and gene expression, leading to inhibition of apoptosis and activation of oncogenic pathways. siRNA interference of multiple DPF3-deregulated genes reduces growth. Our results indicate that germline variation in DPF3, a component of the BAF complex, part of the SWI/SNF complexes, can lead to reduced apoptosis and activation of the STAT3 pathway, both critical in RCC carcinogenesis. In addition, we show that altered DPF3 expression in the 14q24 RCC locus could influence the effectiveness of immunotherapy treatment for RCC by regulating tumor cytokine secretion and immune cell activation.


Subject(s)
Carcinoma, Renal Cell/genetics , Chromosomes, Human, Pair 14 , DNA-Binding Proteins/genetics , Genetic Loci , Kidney Neoplasms/genetics , STAT3 Transcription Factor/genetics , Transcription Factors/genetics , Carcinogenesis/genetics , Carcinogenesis/immunology , Carcinogenesis/pathology , Carcinoma, Renal Cell/immunology , Carcinoma, Renal Cell/pathology , Carcinoma, Renal Cell/therapy , Cell Line, Tumor , Chromatin/chemistry , Chromatin/immunology , Chromatin Assembly and Disassembly/immunology , Cytokines/genetics , Cytokines/immunology , DNA-Binding Proteins/immunology , Gene Expression Regulation , Genetic Predisposition to Disease , Genome, Human , Genome-Wide Association Study , High-Throughput Nucleotide Sequencing , Humans , Immunotherapy/methods , Kidney Neoplasms/immunology , Kidney Neoplasms/pathology , Kidney Neoplasms/therapy , Polymorphism, Single Nucleotide , STAT3 Transcription Factor/immunology , T-Lymphocytes, Cytotoxic , Transcription Factors/immunology
13.
Am J Hum Genet ; 108(9): 1611-1630, 2021 09 02.
Article in English | MEDLINE | ID: mdl-34343493

ABSTRACT

Genome-wide association studies (GWASs) have identified a melanoma-associated locus on chromosome band 7p21.1 with rs117132860 as the lead SNP and a secondary independent signal marked by rs73069846. rs117132860 is also associated with tanning ability and cutaneous squamous cell carcinoma (cSCC). Because ultraviolet radiation (UVR) is a key environmental exposure for all three traits, we investigated the mechanisms by which this locus contributes to melanoma risk, focusing on cellular response to UVR. Fine-mapping of melanoma GWASs identified four independent sets of candidate causal variants. A GWAS region-focused Capture-C study of primary melanocytes identified physical interactions between two causal sets and the promoter of the aryl hydrocarbon receptor (AHR). Subsequent chromatin state annotation, eQTL, and luciferase assays identified rs117132860 as a functional variant and reinforced AHR as a likely causal gene. Because AHR plays critical roles in cellular response to dioxin and UVR, we explored links between this SNP and AHR expression after both 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and ultraviolet B (UVB) exposure. Allele-specific AHR binding to rs117132860-G was enhanced following both, consistent with predicted weakened AHR binding to the risk/poor-tanning rs117132860-A allele, and allele-preferential AHR expression driven from the protective rs117132860-G allele was observed following UVB exposure. Small deletions surrounding rs117132860 introduced via CRISPR abrogates AHR binding, reduces melanocyte cell growth, and prolongs growth arrest following UVB exposure. These data suggest AHR is a melanoma susceptibility gene at the 7p21.1 risk locus and rs117132860 is a functional variant within a UVB-responsive element, leading to allelic AHR expression and altering melanocyte growth phenotypes upon exposure.


Subject(s)
Basic Helix-Loop-Helix Transcription Factors/genetics , Carcinoma, Squamous Cell/genetics , Chromosomes, Human, Pair 7 , Genetic Loci , Melanocytes/metabolism , Melanoma/genetics , Receptors, Aryl Hydrocarbon/genetics , Skin Neoplasms/genetics , Alleles , Basic Helix-Loop-Helix Transcription Factors/metabolism , Carcinogenesis/genetics , Carcinogenesis/metabolism , Carcinogenesis/pathology , Carcinoma, Squamous Cell/metabolism , Carcinoma, Squamous Cell/pathology , Chromatin/chemistry , Chromatin/metabolism , Gene Expression Regulation , Genetic Predisposition to Disease , Genome, Human , Genome-Wide Association Study , Humans , Melanocytes/drug effects , Melanocytes/pathology , Melanocytes/radiation effects , Melanoma/metabolism , Melanoma/pathology , Polychlorinated Dibenzodioxins/toxicity , Polymorphism, Single Nucleotide , Primary Cell Culture , Promoter Regions, Genetic , Receptors, Aryl Hydrocarbon/metabolism , Skin Neoplasms/metabolism , Skin Neoplasms/pathology , Sunbathing , Ultraviolet Rays/adverse effects
14.
Int J Health Geogr ; 20(1): 13, 2021 03 18.
Article in English | MEDLINE | ID: mdl-33736677

ABSTRACT

BACKGROUND: Cancer epidemiology studies require sufficient power to assess spatial relationships between exposures and cancer incidence accurately. However, methods for power calculations of spatial statistics are complicated and underdeveloped, and therefore underutilized by investigators. The spatial relative risk function, a cluster detection technique that detects spatial clusters of point-level data for two groups (e.g., cancer cases and controls, two exposure groups), is a commonly used spatial statistic but does not have a readily available power calculation for study design. RESULTS: We developed sparrpowR as an open-source R package to estimate the statistical power of the spatial relative risk function. sparrpowR generates simulated data applying user-defined parameters (e.g., sample size, locations) to detect spatial clusters with high statistical power. We present applications of sparrpowR that perform a power calculation for a study designed to detect a spatial cluster of incident cancer in relation to a point source of numerous environmental emissions. The conducted power calculations demonstrate the functionality and utility of sparrpowR to calculate the local power for spatial cluster detection. CONCLUSIONS: sparrpowR improves the current capacity of investigators to calculate the statistical power of spatial clusters, which assists in designing more efficient studies. This newly developed R package addresses a critically underdeveloped gap in cancer epidemiology by estimating statistical power for a common spatial cluster detection technique.


Subject(s)
Neoplasms , Cluster Analysis , Humans , Incidence , Spatial Analysis
15.
J Med Chem ; 64(1): 719-740, 2021 01 14.
Article in English | MEDLINE | ID: mdl-33395287

ABSTRACT

Phenotypic screening of a Medicines for Malaria Venture compound library against Mycobacterium tuberculosis (Mtb) identified a cluster of pan-active 2-pyrazolylpyrimidinones. The biology triage of these actives using various tool strains of Mtb suggested a novel mechanism of action. The compounds were bactericidal against replicating Mtb and retained potency against clinical isolates of Mtb. Although selected MmpL3 mutant strains of Mtb showed resistance to these compounds, there was no shift in the minimum inhibitory concentration (MIC) against a mmpL3 hypomorph, suggesting mutations in MmpL3 as a possible resistance mechanism for the compounds but not necessarily as the target. RNA transcriptional profiling and the checkerboard board 2D-MIC assay in the presence of varying concentrations of ferrous salt indicated perturbation of the Fe-homeostasis by the compounds. Structure-activity relationship studies identified potent compounds with good physicochemical properties and in vitro microsomal metabolic stability with moderate selectivity over cytotoxicity against mammalian cell lines.


Subject(s)
Antitubercular Agents/chemistry , Pyrimidinones/chemistry , Animals , Antitubercular Agents/metabolism , Antitubercular Agents/pharmacology , Bacterial Proteins/antagonists & inhibitors , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Half-Life , Humans , Iron/metabolism , Male , Membrane Transport Proteins/genetics , Membrane Transport Proteins/metabolism , Mice , Mice, Inbred C57BL , Microbial Sensitivity Tests , Microsomes/metabolism , Mutation , Mycobacterium tuberculosis/drug effects , Mycobacterium tuberculosis/isolation & purification , Pyrazoles/chemistry , Pyrimidinones/metabolism , Pyrimidinones/pharmacology , Rats , Structure-Activity Relationship
16.
Bioinformatics ; 37(8): 1178-1181, 2021 05 23.
Article in English | MEDLINE | ID: mdl-32926120

ABSTRACT

SUMMARY: A concern when conducting genome-wide association studies (GWAS) is the potential for population stratification, i.e. ancestry-based genetic differences between cases and controls, that if not properly accounted for, could lead to biased association results. We developed PCAmatchR as an open source R package for performing optimal case-control matching using principal component analysis (PCA) to aid in selecting controls that are well matched by ancestry to cases. PCAmatchR takes user supplied PCA outputs and selects matching controls for cases by utilizing a weighted Mahalanobis distance metric which weights each principal component by the percentage of genetic variation explained. Results from the 1000 Genomes Project data demonstrate both the functionality and performance of PCAmatchR for selecting matching controls for case populations as well as reducing inflation of association test statistics. PCAmatchR improves genomic similarity between matched cases and controls, which minimizes the effects of population stratification in GWAS analyses. AVAILABILITY AND IMPLEMENTATION: PCAmatchR is freely available for download on GitHub (https://github.com/machiela-lab/PCAmatchR) or through CRAN (https://CRAN.R-project.org/package=PCAmatchR). SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Subject(s)
Genome-Wide Association Study , Software , Case-Control Studies , Genomics , Principal Component Analysis
17.
Hepatology ; 73(1): 247-267, 2021 01.
Article in English | MEDLINE | ID: mdl-32222998

ABSTRACT

BACKGROUND AND AIMS: Organoids provide a powerful system to study epithelia in vitro. Recently, this approach was applied successfully to the biliary tree, a series of ductular tissues responsible for the drainage of bile and pancreatic secretions. More precisely, organoids have been derived from ductal tissue located outside (extrahepatic bile ducts; EHBDs) or inside the liver (intrahepatic bile ducts; IHBDs). These organoids share many characteristics, including expression of cholangiocyte markers such as keratin (KRT) 19. However, the relationship between these organoids and their tissues of origin, and to each other, is largely unknown. APPROACH AND RESULTS: Organoids were derived from human gallbladder, common bile duct, pancreatic duct, and IHBDs using culture conditions promoting WNT signaling. The resulting IHBD and EHBD organoids expressed stem/progenitor markers leucine-rich repeat-containing G-protein-coupled receptor 5/prominin 1 and ductal markers KRT19/KRT7. However, RNA sequencing revealed that organoids conserve only a limited number of regional-specific markers corresponding to their location of origin. Of particular interest, down-regulation of biliary markers and up-regulation of cell-cycle genes were observed in organoids. IHBD and EHBD organoids diverged in their response to WNT signaling, and only IHBDs were able to express a low level of hepatocyte markers under differentiation conditions. CONCLUSIONS: Taken together, our results demonstrate that differences exist not only between extrahepatic biliary organoids and their tissue of origin, but also between IHBD and EHBD organoids. This information may help to understand the tissue specificity of cholangiopathies and also to identify targets for therapeutic development.


Subject(s)
Bile Ducts, Extrahepatic/cytology , Bile Ducts, Intrahepatic/cytology , Epithelial Cells/cytology , Organoids/physiology , Animals , Bile , Bile Ducts, Extrahepatic/physiology , Bile Ducts, Intrahepatic/physiology , Cell Differentiation , Common Bile Duct/cytology , Epithelial Cells/physiology , Gallbladder/cytology , Gene Expression Regulation , Humans , Keratin-19/analysis , Liver/physiology , Mice , RNA-Seq , Tissue and Organ Procurement
18.
Sci Transl Med ; 12(560)2020 09 09.
Article in English | MEDLINE | ID: mdl-32908007

ABSTRACT

Dysbiosis of the skin microbiota is increasingly implicated as a contributor to the pathogenesis of atopic dermatitis (AD). We previously reported first-in-human safety and clinical activity results from topical application of the commensal skin bacterium Roseomonas mucosa for the treatment of AD in 10 adults and 5 children older than 9 years of age. Here, we examined the potential mechanism of action of R. mucosa treatment and its impact on children with AD less than 7 years of age, the most common age group for children with AD. In 15 children with AD, R. mucosa treatment was associated with amelioration of disease severity, improvement in epithelial barrier function, reduced Staphylococcus aureus burden on the skin, and a reduction in topical steroid requirements without severe adverse events. Our observed response rates to R. mucosa treatment were greater than those seen in historical placebo control groups in prior AD studies. Skin improvements and colonization by R. mucosa persisted for up to 8 months after cessation of treatment. Analyses of cellular scratch assays and the MC903 mouse model of AD suggested that production of sphingolipids by R. mucosa, cholinergic signaling, and flagellin expression may have contributed to therapeutic impact through induction of a TNFR2-mediated epithelial-to-mesenchymal transition. These results suggest that a randomized, placebo-controlled trial of R. mucosa treatment in individuals with AD is warranted and implicate commensals in the maintenance of the skin epithelial barrier.


Subject(s)
Dermatitis, Atopic , Eczema , Methylobacteriaceae , Adult , Child , Dermatitis, Atopic/drug therapy , Humans , Lipids , Skin
19.
Proc Natl Acad Sci U S A ; 117(32): 19465-19474, 2020 08 11.
Article in English | MEDLINE | ID: mdl-32709745

ABSTRACT

Infection by malaria parasites triggers dynamic immune responses leading to diverse symptoms and pathologies; however, the molecular mechanisms responsible for these reactions are largely unknown. We performed Trans-species Expression Quantitative Trait Locus analysis to identify a large number of host genes that respond to malaria parasite infections. Here we functionally characterize one of the host genes called receptor transporter protein 4 (RTP4) in responses to malaria parasite and virus infections. RTP4 is induced by type I IFN (IFN-I) and binds to the TANK-binding kinase (TBK1) complex where it negatively regulates TBK1 signaling by interfering with expression and phosphorylation of both TBK1 and IFN regulatory factor 3. Rtp4-/- mice were generated and infected with malaria parasite Plasmodiun berghei ANKA. Significantly higher levels of IFN-I response in microglia, lower parasitemia, fewer neurologic symptoms, and better survival rates were observed in Rtp4-/- than in wild-type mice. Similarly, RTP4 deficiency significantly reduced West Nile virus titers in the brain, but not in the heart and the spleen, of infected mice, suggesting a specific role for RTP4 in brain infection and pathology. This study reveals functions of RTP4 in IFN-I response and a potential target for therapy in diseases with neuropathology.


Subject(s)
Brain/pathology , Interferon Type I/metabolism , Malaria, Cerebral/pathology , Molecular Chaperones/metabolism , Animals , Brain/parasitology , Brain/virology , HEK293 Cells , Host-Pathogen Interactions , Humans , Interferon Regulatory Factor-3 , Malaria, Cerebral/metabolism , Malaria, Cerebral/parasitology , Membrane Proteins , Mice , Mice, Inbred C57BL , Mice, Knockout , Microglia/metabolism , Molecular Chaperones/genetics , Phosphorylation , Plasmodium berghei/physiology , Plasmodium yoelii/physiology , Protein Binding , Protein Serine-Threonine Kinases/metabolism , Signal Transduction , West Nile Fever/metabolism , West Nile Fever/pathology , West Nile Fever/virology , West Nile virus/physiology
20.
Proc Natl Acad Sci U S A ; 117(28): 16567-16578, 2020 07 14.
Article in English | MEDLINE | ID: mdl-32606244

ABSTRACT

Malaria infection induces complex and diverse immune responses. To elucidate the mechanisms underlying host-parasite interaction, we performed a genetic screen during early (24 h) Plasmodium yoelii infection in mice and identified a large number of interacting host and parasite genes/loci after transspecies expression quantitative trait locus (Ts-eQTL) analysis. We next investigated a host E3 ubiquitin ligase gene (March1) that was clustered with interferon (IFN)-stimulated genes (ISGs) based on the similarity of the genome-wide pattern of logarithm of the odds (LOD) scores (GPLS). March1 inhibits MAVS/STING/TRIF-induced type I IFN (IFN-I) signaling in vitro and in vivo. However, in malaria-infected hosts, deficiency of March1 reduces IFN-I production by activating inhibitors such as SOCS1, USP18, and TRIM24 and by altering immune cell populations. March1 deficiency increases CD86+DC (dendritic cell) populations and levels of IFN-γ and interleukin 10 (IL-10) at day 4 post infection, leading to improved host survival. T cell depletion reduces IFN-γ level and reverse the protective effects of March1 deficiency, which can also be achieved by antibody neutralization of IFN-γ. This study reveals functions of MARCH1 (membrane-associated ring-CH-type finger 1) in innate immune responses and provides potential avenues for activating antimalaria immunity and enhancing vaccine efficacy.


Subject(s)
Malaria/immunology , Plasmodium yoelii/physiology , T-Lymphocytes/immunology , Ubiquitin-Protein Ligases/immunology , Animals , Disease Models, Animal , Female , Host-Parasite Interactions , Humans , Immunity, Innate , Interferon Type I/genetics , Interferon Type I/immunology , Interferon-gamma/genetics , Interferon-gamma/immunology , Interleukin-10/genetics , Interleukin-10/immunology , Malaria/enzymology , Malaria/genetics , Malaria/parasitology , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Plasmodium yoelii/immunology , Ubiquitin-Protein Ligases/genetics
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