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1.
Sci Total Environ ; 917: 170398, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38281636

RESUMEN

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.

2.
J Immunol ; 210(11): 1700-1716, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-37093875

RESUMEN

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.


Asunto(s)
Enfermedades Autoinmunes , Células Th17 , Humanos , Diferenciación Celular , Fenotipo , Receptores CCR6/genética , Células TH1/metabolismo
3.
J Exp Med ; 220(8)2023 08 07.
Artículo en Inglés | MEDLINE | ID: mdl-37097292

RESUMEN

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.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis , Animales , Ratones , Linfocitos T CD4-Positivos , Diferenciación Celular , Granuloma/metabolismo , Macaca mulatta , Tuberculosis/microbiología , Antígeno Ki-1/inmunología
4.
bioRxiv ; 2023 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-36789418

RESUMEN

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.

5.
bioRxiv ; 2023 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-36789428

RESUMEN

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.

7.
Clin Cancer Res ; 29(2): 349-363, 2023 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-36099324

RESUMEN

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.


Asunto(s)
Monocitos , Neoplasias Ováricas , Humanos , Femenino , Monocitos/metabolismo , Apoptosis , Interferón-alfa/uso terapéutico , Neoplasias Ováricas/tratamiento farmacológico , Inmunoterapia , Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo , Receptores del Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo
8.
iScience ; 25(1): 103588, 2022 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-35005538

RESUMEN

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.

9.
J Med Chem ; 64(17): 12790-12807, 2021 09 09.
Artículo en Inglés | MEDLINE | ID: mdl-34414766

RESUMEN

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.


Asunto(s)
Antituberculosos/farmacología , Pared Celular/metabolismo , Mycobacterium tuberculosis/efectos de los fármacos , Sulfonamidas/farmacología , Antituberculosos/síntesis química , Antituberculosos/química , Descubrimiento de Drogas , Células Hep G2 , Humanos , Pruebas de Sensibilidad Microbiana , Modelos Moleculares , Estructura Molecular , Mycobacterium tuberculosis/metabolismo , Relación Estructura-Actividad , Sulfonamidas/química
10.
J Med Chem ; 64(1): 719-740, 2021 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-33395287

RESUMEN

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.


Asunto(s)
Antituberculosos/química , Pirimidinonas/química , Animales , Antituberculosos/metabolismo , Antituberculosos/farmacología , Proteínas Bacterianas/antagonistas & inhibidores , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Semivida , Humanos , Hierro/metabolismo , Masculino , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Pruebas de Sensibilidad Microbiana , Microsomas/metabolismo , Mutación , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/aislamiento & purificación , Pirazoles/química , Pirimidinonas/metabolismo , Pirimidinonas/farmacología , Ratas , Relación Estructura-Actividad
11.
Hepatology ; 73(1): 247-267, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32222998

RESUMEN

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.


Asunto(s)
Conductos Biliares Extrahepáticos/citología , Conductos Biliares Intrahepáticos/citología , Células Epiteliales/citología , Organoides/fisiología , Animales , Bilis , Conductos Biliares Extrahepáticos/fisiología , Conductos Biliares Intrahepáticos/fisiología , Diferenciación Celular , Conducto Colédoco/citología , Células Epiteliales/fisiología , Vesícula Biliar/citología , Regulación de la Expresión Génica , Humanos , Queratina-19/análisis , Hígado/fisiología , Ratones , RNA-Seq , Obtención de Tejidos y Órganos
12.
Sci Transl Med ; 12(560)2020 09 09.
Artículo en Inglés | MEDLINE | ID: mdl-32908007

RESUMEN

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.


Asunto(s)
Dermatitis Atópica , Eccema , Methylobacteriaceae , Adulto , Niño , Dermatitis Atópica/tratamiento farmacológico , Humanos , Lípidos , Piel
13.
Proc Natl Acad Sci U S A ; 117(32): 19465-19474, 2020 08 11.
Artículo en Inglés | MEDLINE | ID: mdl-32709745

RESUMEN

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.


Asunto(s)
Encéfalo/patología , Interferón Tipo I/metabolismo , Malaria Cerebral/patología , Chaperonas Moleculares/metabolismo , Animales , Encéfalo/parasitología , Encéfalo/virología , Células HEK293 , Interacciones Huésped-Patógeno , Humanos , Factor 3 Regulador del Interferón , Malaria Cerebral/metabolismo , Malaria Cerebral/parasitología , Proteínas de la Membrana , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Microglía/metabolismo , Chaperonas Moleculares/genética , Fosforilación , Plasmodium berghei/fisiología , Plasmodium yoelii/fisiología , Unión Proteica , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal , Fiebre del Nilo Occidental/metabolismo , Fiebre del Nilo Occidental/patología , Fiebre del Nilo Occidental/virología , Virus del Nilo Occidental/fisiología
14.
Proc Natl Acad Sci U S A ; 117(28): 16567-16578, 2020 07 14.
Artículo en Inglés | MEDLINE | ID: mdl-32606244

RESUMEN

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.


Asunto(s)
Malaria/inmunología , Plasmodium yoelii/fisiología , Linfocitos T/inmunología , Ubiquitina-Proteína Ligasas/inmunología , Animales , Modelos Animales de Enfermedad , Femenino , Interacciones Huésped-Parásitos , Humanos , Inmunidad Innata , Interferón Tipo I/genética , Interferón Tipo I/inmunología , Interferón gamma/genética , Interferón gamma/inmunología , Interleucina-10/genética , Interleucina-10/inmunología , Malaria/enzimología , Malaria/genética , Malaria/parasitología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Plasmodium yoelii/inmunología , Ubiquitina-Proteína Ligasas/genética
15.
Sci Immunol ; 5(44)2020 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-32111619

RESUMEN

We investigated the molecular and cellular basis of severe combined immunodeficiency (SCID) in six patients with otofaciocervical syndrome type 2 who failed to attain T cell reconstitution after allogeneic hematopoietic stem cell transplantation, despite successful engraftment in three of them. We identified rare biallelic PAX1 rare variants in all patients. We demonstrated that these mutant PAX1 proteins have an altered conformation and flexibility of the paired box domain and reduced transcriptional activity. We generated patient-derived induced pluripotent stem cells and differentiated them into thymic epithelial progenitor cells and found that they have an altered transcriptional profile, including for genes involved in the development of the thymus and other tissues derived from pharyngeal pouches. These results identify biallelic, loss-of-function PAX1 mutations as the cause of a syndromic form of SCID due to altered thymus development.


Asunto(s)
Factores de Transcripción Paired Box/inmunología , Timo/inmunología , Síndrome Branquio Oto Renal/genética , Síndrome Branquio Oto Renal/inmunología , Síndrome Branquio Oto Renal/patología , Células Epiteliales/inmunología , Células Epiteliales/patología , Humanos , Lactante , Masculino , Factores de Transcripción Paired Box/genética , Inmunodeficiencia Combinada Grave/genética , Inmunodeficiencia Combinada Grave/inmunología , Inmunodeficiencia Combinada Grave/patología , Timo/patología
16.
Tuberculosis (Edinb) ; 120: 101895, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-32090856

RESUMEN

New vaccines are needed to combat the public health threat posed by M. tuberculosis (M. tb), but no correlates have been defined to aid vaccine development. Using mouse models, we previously developed an in vitro system that measures the ability of M. tb-immune lymphocytes to control bacterial replication during co-culture with M. tb-infected macrophages. We demonstrated that the degree of in vitro growth control by lymphocytes from mice given vaccines of varying efficacy reflected the relative degree of in vivo protection against lethal challenge. Further, using targeted analyses of gene expression in lymphocytes recovered from co-cultures, we found mediators whose relative expression also correlated with in vitro and in vivo outcomes. Here we advanced those findings by employing genome-wide expression analyses. We first screened splenocytes recovered from co-cultures by microarray, revealing additional genes whose expression correlated with protection. After applying pathway analyses to down-select gene candidates, we used both splenocytes and peripheral blood lymphocytes to validate microarray findings by qRT-PCR. We then subjected data from top candidates to rigorous statistical analyses. Resulting correlate candidates, including CXCL9, IFN-γ, and CCL5, significantly predicted protection with high specificity. These findings therefore refine and extend a panel of relevant immune correlates to advance vaccine development.


Asunto(s)
Perfilación de la Expresión Génica , Macrófagos/efectos de los fármacos , Mycobacterium tuberculosis/efectos de los fármacos , Linfocitos T/efectos de los fármacos , Transcriptoma , Vacunas contra la Tuberculosis/farmacología , Animales , Células Cultivadas , Quimiocina CCL5/genética , Quimiocina CXCL9/genética , Técnicas de Cocultivo , Estudio de Asociación del Genoma Completo , Interferón gamma/genética , Macrófagos/inmunología , Macrófagos/microbiología , Masculino , Ratones Endogámicos C57BL , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/crecimiento & desarrollo , Mycobacterium tuberculosis/inmunología , Análisis de Secuencia por Matrices de Oligonucleótidos , Linfocitos T/inmunología , Vacunación
17.
mBio ; 11(1)2020 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-31911494

RESUMEN

Erythrocyte-binding-like (EBL) proteins are known to play an important role in malaria parasite invasion of red blood cells (RBCs); however, any roles of EBL proteins in regulating host immune responses remain unknown. Here, we show that Plasmodium yoelii EBL (PyEBL) can shape disease severity by modulating the surface structure of infected RBCs (iRBCs) and host immune responses. We identified an amino acid substitution (a change of C to Y at position 741 [C741Y]) in the protein trafficking domain of PyEBL between isogenic P. yoelliinigeriensis strain N67 and N67C parasites that produce different disease phenotypes in C57BL/6 mice. Exchanges of the C741Y alleles altered parasite growth and host survival accordingly. The C741Y substitution also changed protein processing and trafficking in merozoites and in the cytoplasm of iRBCs, reduced PyEBL binding to band 3, increased phosphatidylserine (PS) surface exposure, and elevated the osmotic fragility of iRBCs, but it did not affect invasion of RBCs in vitro The modified iRBC surface triggered PS-CD36-mediated phagocytosis of iRBCs, host type I interferon (IFN-I) signaling, and T cell differentiation, leading to improved host survival. This study reveals a previously unknown role of PyEBL in regulating host-pathogen interaction and innate immune responses, which may be explored for developing disease control strategies.IMPORTANCE Malaria is a deadly parasitic disease that continues to afflict hundreds of millions of people every year. Infections with malaria parasites can be asymptomatic, with mild symptoms, or fatal, depending on a delicate balance of host immune responses. Malaria parasites enter host red blood cells (RBCs) through interactions between parasite ligands and host receptors, such as erythrocyte-binding-like (EBL) proteins and host Duffy antigen receptor for chemokines (DARC). Plasmodium yoelii EBL (PyEBL) is known to play a role in parasite invasion of RBCs. Here, we show that PyEBL also affects disease severity through modulation of host immune responses, particularly type I interferon (IFN-I) signaling. This discovery assigns a new function to PyEBL and provides a mechanism for developing disease control strategies.


Asunto(s)
Antígenos de Protozoos/inmunología , Eritrocitos/inmunología , Eritrocitos/parasitología , Malaria/inmunología , Malaria/parasitología , Proteínas de la Membrana/metabolismo , Plasmodium yoelii/fisiología , Proteínas Protozoarias/metabolismo , Alelos , Antígenos de Protozoos/metabolismo , Biomarcadores , Citocinas/metabolismo , Técnica del Anticuerpo Fluorescente , Interacciones Huésped-Parásitos , Inmunohistoquímica , Malaria/diagnóstico , Malaria/metabolismo , Proteínas de la Membrana/inmunología , Fragilidad Osmótica , Fagocitosis/inmunología , Proteínas Protozoarias/genética , Proteínas Protozoarias/inmunología , Índice de Severidad de la Enfermedad , Bazo/inmunología , Bazo/metabolismo , Bazo/patología , Linfocitos T Colaboradores-Inductores/inmunología , Linfocitos T Colaboradores-Inductores/metabolismo
18.
Curr Protoc Immunol ; 126(1): e78, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31483103

RESUMEN

MicroRNAs (miRNAs) are short (19- to 25-nucleotide) noncoding RNA molecules that target mRNAs to repress gene expression and that play important roles in regulating many fundamental biological functions including cell differentiation, development, growth, and metabolism. They are well conserved in eukaryotic cells and are considered essential ancient elements of gene regulation. miRNA genes are transcribed by RNA polymerase II to generate primary miRNAs (pri-miRNAs), which are cleaved by microprocessor complex in the nucleus to generate stem-loop structures known as pre-miRNAs. Pre-miRNAs are translocated to the cytoplasm and cleaved by Dicer to form the mature miRNAs, which mediate mRNA degradation through their loading to the RNA-induced silencing complex (RISC) and binding to complementary sequences within target mRNAs to repress their translation by mRNA degradation and/or translation inhibition. Because ∼1900 miRNA genes are reported in the human genome, many associated with disease, appropriate methods to study miRNA expression and regulation under physiological and pathological conditions have become increasingly important to the study of many aspects of human biology, including immune regulation. As with small interfering RNA (siRNA), the mechanism of miRNA-mediated targeting has been used to develop miRNA-based therapeutics. For a complete and systematic analysis, it is critical to utilize a variety of different tools to analyze the expression of pri-mRNAs, pre-miRNAs, and mature miRNAs and characterize their targets both in vitro and in vivo. Such studies will facilitate future novel drug design and development. This unit provides six basic protocols for miRNA analysis, covering next-generation sequencing, quantitative real-time PCR (qRT-PCR), and digoxigenin-based expression analysis of pri-mRNAs, pre-miRNAs, and mature miRNAs; mapping of pri-miRNA and their cleavage sites by rapid amplification of cDNA ends (RACE); electrophoretic mobility shift assays (EMSAs) or biotin-based nonradioactive detection of miRNA-protein complexes (miRNPs); and functional analysis of miRNAs using miRNA mimics and inhibitors. © 2019 by John Wiley & Sons, Inc.


Asunto(s)
Biomimética/métodos , MicroARNs/genética , ARN Mensajero/genética , Ensayo de Cambio de Movilidad Electroforética , Expresión Génica , Regulación de la Expresión Génica , Silenciador del Gen , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Imitación Molecular
19.
Blood ; 133(26): 2753-2764, 2019 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-31064750

RESUMEN

Patients with classic hydroa vacciniforme-like lymphoproliferative disorder (HVLPD) typically have high levels of Epstein-Barr virus (EBV) DNA in T cells and/or natural killer (NK) cells in blood and skin lesions induced by sun exposure that are infiltrated with EBV-infected lymphocytes. HVLPD is very rare in the United States and Europe but more common in Asia and South America. The disease can progress to a systemic form that may result in fatal lymphoma. We report our 11-year experience with 16 HVLPD patients from the United States and England and found that whites were less likely to develop systemic EBV disease (1/10) than nonwhites (5/6). All (10/10) of the white patients were generally in good health at last follow-up, while two-thirds (4/6) of the nonwhite patients required hematopoietic stem cell transplantation. Nonwhite patients had later age of onset of HVLPD than white patients (median age, 8 vs 5 years) and higher levels of EBV DNA (median, 1 515 000 vs 250 000 copies/ml) and more often had low numbers of NK cells (83% vs 50% of patients) and T-cell clones in the blood (83% vs 30% of patients). RNA-sequencing analysis of an HVLPD skin lesion in a white patient compared with his normal skin showed increased expression of interferon-γ and chemokines that attract T cells and NK cells. Thus, white patients with HVLPD were less likely to have systemic disease with EBV and had a much better prognosis than nonwhite patients. This trial was registered at www.clinicaltrials.gov as #NCT00369421 and #NCT00032513.


Asunto(s)
Infecciones por Virus de Epstein-Barr/patología , Hidroa Vacciniforme/virología , Trastornos Linfoproliferativos/patología , Trastornos Linfoproliferativos/virología , Niño , Preescolar , Infecciones por Virus de Epstein-Barr/etnología , Infecciones por Virus de Epstein-Barr/inmunología , Femenino , Humanos , Trastornos Linfoproliferativos/etnología , Masculino , Población Blanca
20.
Mucosal Immunol ; 12(1): 85-96, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30087442

RESUMEN

Despite studies indicating the effects of IL-21 signaling in intestinal inflammation, its roles in intestinal homeostasis and infection are not yet clear. Here, we report potent effects of commensal microbiota on the phenotypic manifestations of IL-21 receptor deficiency. IL-21 is produced highly in the small intestine and appears to be critical for mounting an IgA response against atypical commensals such as segmented filamentous bacteria and Helicobacter, but not to the majority of commensals. In the presence of these atypical commensals, IL-21R-deficient mice exhibit reduced numbers of germinal center and IgA+ B cells and expression of activation-induced cytidine deaminase in Peyer's patches as well as a significant decrease in small intestine IgA+ plasmablasts and plasma cells, leading to higher bacterial burdens and subsequent expansion of Th17 and Treg cells. These microbiota-mediated secondary changes in turn enhance T cell responses to an oral antigen and strikingly dampen Citrobacter rodentium-induced immunopathology, demonstrating a complex interplay between IL-21-mediated mucosal immunity, microbiota, and pathogens.


Asunto(s)
Formas Bacterianas Atípicas/fisiología , Linfocitos B/fisiología , Citrobacter rodentium/fisiología , Infecciones por Enterobacteriaceae/inmunología , Helicobacter/fisiología , Inmunoglobulina A/metabolismo , Mucosa Intestinal/inmunología , Intestino Delgado/inmunología , Receptores de Interleucina-21/genética , Animales , Carga Bacteriana , Diferenciación Celular , Células Cultivadas , Citidina Desaminasa/genética , Citidina Desaminasa/metabolismo , Homeostasis , Humanos , Inmunidad Humoral , Inmunidad Mucosa , Mucosa Intestinal/microbiología , Intestino Delgado/microbiología , Ratones , Ratones Noqueados , Receptores de Interleucina-21/metabolismo , Linfocitos T Reguladores/inmunología , Células Th17/inmunología
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