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1.
Nat Immunol ; 24(7): 1173-1187, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37291385

RESUMEN

Blood protein extravasation through a disrupted blood-brain barrier and innate immune activation are hallmarks of neurological diseases and emerging therapeutic targets. However, how blood proteins polarize innate immune cells remains largely unknown. Here, we established an unbiased blood-innate immunity multiomic and genetic loss-of-function pipeline to define the transcriptome and global phosphoproteome of blood-induced innate immune polarization and its role in microglia neurotoxicity. Blood induced widespread microglial transcriptional changes, including changes involving oxidative stress and neurodegenerative genes. Comparative functional multiomics showed that blood proteins induce distinct receptor-mediated transcriptional programs in microglia and macrophages, such as redox, type I interferon and lymphocyte recruitment. Deletion of the blood coagulation factor fibrinogen largely reversed blood-induced microglia neurodegenerative signatures. Genetic elimination of the fibrinogen-binding motif to CD11b in Alzheimer's disease mice reduced microglial lipid metabolism and neurodegenerative signatures that were shared with autoimmune-driven neuroinflammation in multiple sclerosis mice. Our data provide an interactive resource for investigation of the immunology of blood proteins that could support therapeutic targeting of microglia activation by immune and vascular signals.


Asunto(s)
Enfermedad de Alzheimer , Microglía , Ratones , Animales , Microglía/metabolismo , Multiómica , Barrera Hematoencefálica/metabolismo , Enfermedad de Alzheimer/genética , Fibrinógeno
2.
Cell ; 181(7): 1502-1517.e23, 2020 06 25.
Artículo en Inglés | MEDLINE | ID: mdl-32559462

RESUMEN

RNA viruses are a major human health threat. The life cycles of many highly pathogenic RNA viruses like influenza A virus (IAV) and Lassa virus depends on host mRNA, because viral polymerases cleave 5'-m7G-capped host transcripts to prime viral mRNA synthesis ("cap-snatching"). We hypothesized that start codons within cap-snatched host transcripts could generate chimeric human-viral mRNAs with coding potential. We report the existence of this mechanism of gene origination, which we named "start-snatching." Depending on the reading frame, start-snatching allows the translation of host and viral "untranslated regions" (UTRs) to create N-terminally extended viral proteins or entirely novel polypeptides by genetic overprinting. We show that both types of chimeric proteins are made in IAV-infected cells, generate T cell responses, and contribute to virulence. Our results indicate that during infection with IAV, and likely a multitude of other human, animal and plant viruses, a host-dependent mechanism allows the genesis of hybrid genes.


Asunto(s)
Caperuzas de ARN/genética , Infecciones por Virus ARN/genética , Proteínas Recombinantes de Fusión/genética , Regiones no Traducidas 5'/genética , Animales , Bovinos , Línea Celular , Cricetinae , Perros , Humanos , Virus de la Influenza A/metabolismo , Ratones , Proteínas Mutantes Quiméricas/genética , Proteínas Mutantes Quiméricas/metabolismo , Sistemas de Lectura Abierta/genética , Caperuzas de ARN/metabolismo , Infecciones por Virus ARN/metabolismo , Virus ARN/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Viral/metabolismo , ARN Polimerasa Dependiente del ARN/genética , ARN Polimerasa Dependiente del ARN/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Transcripción Genética/genética , Proteínas Virales/metabolismo , Replicación Viral/genética
3.
Cell ; 175(7): 1931-1945.e18, 2018 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-30550790

RESUMEN

Mosquito-borne flaviviruses, including dengue virus (DENV) and Zika virus (ZIKV), are a growing public health concern. Systems-level analysis of how flaviviruses hijack cellular processes through virus-host protein-protein interactions (PPIs) provides information about their replication and pathogenic mechanisms. We used affinity purification-mass spectrometry (AP-MS) to compare flavivirus-host interactions for two viruses (DENV and ZIKV) in two hosts (human and mosquito). Conserved virus-host PPIs revealed that the flavivirus NS5 protein suppresses interferon stimulated genes by inhibiting recruitment of the transcription complex PAF1C and that chemical modulation of SEC61 inhibits DENV and ZIKV replication in human and mosquito cells. Finally, we identified a ZIKV-specific interaction between NS4A and ANKLE2, a gene linked to hereditary microcephaly, and showed that ZIKV NS4A causes microcephaly in Drosophila in an ANKLE2-dependent manner. Thus, comparative flavivirus-host PPI mapping provides biological insights and, when coupled with in vivo models, can be used to unravel pathogenic mechanisms.


Asunto(s)
Virus del Dengue , Dengue , Proteínas de la Membrana , Proteínas Nucleares , Proteínas no Estructurales Virales , Infección por el Virus Zika , Virus Zika , Animales , Línea Celular Tumoral , Culicidae , Dengue/genética , Dengue/metabolismo , Dengue/patología , Virus del Dengue/genética , Virus del Dengue/metabolismo , Virus del Dengue/patogenicidad , Células HEK293 , Humanos , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Mapeo de Interacción de Proteínas , Proteínas no Estructurales Virales/genética , Proteínas no Estructurales Virales/metabolismo , Virus Zika/genética , Virus Zika/metabolismo , Virus Zika/patogenicidad , Infección por el Virus Zika/genética , Infección por el Virus Zika/metabolismo , Infección por el Virus Zika/patología
4.
Nature ; 592(7856): 794-798, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33854239

RESUMEN

The initiation of cell division integrates a large number of intra- and extracellular inputs. D-type cyclins (hereafter, cyclin D) couple these inputs to the initiation of DNA replication1. Increased levels of cyclin D promote cell division by activating cyclin-dependent kinases 4 and 6 (hereafter, CDK4/6), which in turn phosphorylate and inactivate the retinoblastoma tumour suppressor. Accordingly, increased levels and activity of cyclin D-CDK4/6 complexes are strongly linked to unchecked cell proliferation and cancer2,3. However, the mechanisms that regulate levels of cyclin D are incompletely understood4,5. Here we show that autophagy and beclin 1 regulator 1 (AMBRA1) is the main regulator of the degradation of cyclin D. We identified AMBRA1 in a genome-wide screen to investigate the genetic basis of  the response to CDK4/6 inhibition. Loss of AMBRA1 results in high levels of cyclin D in cells and in mice, which promotes proliferation and decreases sensitivity to CDK4/6 inhibition. Mechanistically, AMBRA1 mediates ubiquitylation and proteasomal degradation of cyclin D as a substrate receptor for the cullin 4 E3 ligase complex. Loss of AMBRA1 enhances the growth of lung adenocarcinoma in a mouse model, and low levels of AMBRA1 correlate with worse survival in patients with lung adenocarcinoma. Thus, AMBRA1 regulates cellular levels of cyclin D, and contributes to cancer development and the response of cancer cells to CDK4/6 inhibitors.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Ciclina D/metabolismo , Adenocarcinoma del Pulmón/genética , Animales , División Celular , Quinasa 4 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 4 Dependiente de la Ciclina/metabolismo , Quinasa 6 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 6 Dependiente de la Ciclina/metabolismo , Genes Supresores de Tumor , Humanos , Neoplasias Pulmonares/genética , Ratones , Piperazinas/farmacología , Piridinas/farmacología , Células U937 , Ubiquitinación
5.
Mol Cell ; 74(6): 1164-1174.e4, 2019 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-31054975

RESUMEN

Post-translational modifications of the RNA polymerase II C-terminal domain (CTD) coordinate the transcription cycle. Crosstalk between different modifications is poorly understood. Here, we show how acetylation of lysine residues at position 7 of characteristic heptad repeats (K7ac)-only found in higher eukaryotes-regulates phosphorylation of serines at position 5 (S5p), a conserved mark of polymerases initiating transcription. We identified the regulator of pre-mRNA-domain-containing (RPRD) proteins as reader proteins of K7ac. K7ac enhanced CTD peptide binding to the CTD-interacting domain (CID) of RPRD1A and RPRD1B proteins in isothermal calorimetry and molecular modeling experiments. Deacetylase inhibitors increased K7ac- and decreased S5-phosphorylated polymerases, consistent with acetylation-dependent S5 dephosphorylation by an RPRD-associated S5 phosphatase. Consistent with this model, RPRD1B knockdown increased S5p but enhanced K7ac, indicating that RPRD proteins recruit K7 deacetylases, including HDAC1. We also report autoregulatory crosstalk between K7ac and S5p via RPRD proteins and their interactions with acetyl- and phospho-eraser proteins.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Proteínas de Neoplasias/metabolismo , Isoformas de Proteínas/metabolismo , Procesamiento Proteico-Postraduccional , ARN Polimerasa II/metabolismo , Acetilación , Secuencia de Aminoácidos , Animales , Sitios de Unión , Proteínas de Ciclo Celular/antagonistas & inhibidores , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/genética , Células HEK293 , Humanos , Ratones , Modelos Moleculares , Células 3T3 NIH , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Fosforilación , Unión Proteica , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta , Dominios y Motivos de Interacción de Proteínas , Isoformas de Proteínas/antagonistas & inhibidores , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , ARN Polimerasa II/química , ARN Polimerasa II/genética , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Termodinámica
6.
Nature ; 585(7825): 414-419, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32641828

RESUMEN

Zika virus (ZIKV) belongs to the family Flaviviridae, and is related to other viruses that cause human diseases. Unlike other flaviviruses, ZIKV infection can cause congenital neurological disorders and replicates efficiently in reproductive tissues1-3. Here we show that the envelope protein (E) of ZIKV is polyubiquitinated by the E3 ubiquitin ligase TRIM7 through Lys63 (K63)-linked polyubiquitination. Accordingly, ZIKV replicates less efficiently in the brain and reproductive tissues of Trim7-/- mice. Ubiquitinated E is present on infectious virions of ZIKV when they are released from specific cell types, and enhances virus attachment and entry into cells. Specifically, K63-linked polyubiquitin chains directly interact with the TIM1 (also known as HAVCR1) receptor of host cells, which enhances virus entry in cells as well as in brain tissue in vivo. Recombinant ZIKV mutants that lack ubiquitination are attenuated in human cells and in wild-type mice, but not in live mosquitoes. Monoclonal antibodies against K63-linked polyubiquitin specifically neutralize ZIKV and reduce viraemia in mice. Our results demonstrate that the ubiquitination of ZIKV E is an important determinant of virus entry, tropism and pathogenesis.


Asunto(s)
Ubiquitinación , Proteínas del Envoltorio Viral/química , Proteínas del Envoltorio Viral/metabolismo , Internalización del Virus , Virus Zika/metabolismo , Virus Zika/patogenicidad , Animales , Anticuerpos Monoclonales/inmunología , Anticuerpos Neutralizantes/inmunología , Encéfalo/metabolismo , Línea Celular , Culicidae/citología , Culicidae/virología , Endosomas/metabolismo , Femenino , Receptor Celular 1 del Virus de la Hepatitis A/metabolismo , Humanos , Masculino , Fusión de Membrana , Ratones , Especificidad de Órganos , Poliubiquitina/inmunología , Poliubiquitina/metabolismo , Proteínas de Motivos Tripartitos/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Tropismo Viral , Viremia/inmunología , Viremia/prevención & control , Viremia/virología , Replicación Viral , Virus Zika/química , Virus Zika/genética , Infección por el Virus Zika/prevención & control , Infección por el Virus Zika/virología
7.
Nature ; 586(7827): 113-119, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32707573

RESUMEN

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 2019 has triggered an ongoing global pandemic of the severe pneumonia-like disease coronavirus disease 2019 (COVID-19)1. The development of a vaccine is likely to take at least 12-18 months, and the typical timeline for approval of a new antiviral therapeutic agent can exceed 10 years. Thus, repurposing of known drugs could substantially accelerate the deployment of new therapies for COVID-19. Here we profiled a library of drugs encompassing approximately 12,000 clinical-stage or Food and Drug Administration (FDA)-approved small molecules to identify candidate therapeutic drugs for COVID-19. We report the identification of 100 molecules that inhibit viral replication of SARS-CoV-2, including 21 drugs that exhibit dose-response relationships. Of these, thirteen were found to harbour effective concentrations commensurate with probable achievable therapeutic doses in patients, including the PIKfyve kinase inhibitor apilimod2-4 and the cysteine protease inhibitors MDL-28170, Z LVG CHN2, VBY-825 and ONO 5334. Notably, MDL-28170, ONO 5334 and apilimod were found to antagonize viral replication in human pneumocyte-like cells derived from induced pluripotent stem cells, and apilimod also demonstrated antiviral efficacy in a primary human lung explant model. Since most of the molecules identified in this study have already advanced into the clinic, their known pharmacological and human safety profiles will enable accelerated preclinical and clinical evaluation of these drugs for the treatment of COVID-19.


Asunto(s)
Antivirales/análisis , Antivirales/farmacología , Betacoronavirus/efectos de los fármacos , Infecciones por Coronavirus/tratamiento farmacológico , Infecciones por Coronavirus/virología , Evaluación Preclínica de Medicamentos , Reposicionamiento de Medicamentos , Neumonía Viral/tratamiento farmacológico , Neumonía Viral/virología , Adenosina Monofosfato/análogos & derivados , Adenosina Monofosfato/farmacología , Alanina/análogos & derivados , Alanina/farmacología , Células Epiteliales Alveolares/citología , Células Epiteliales Alveolares/efectos de los fármacos , Betacoronavirus/crecimiento & desarrollo , COVID-19 , Línea Celular , Inhibidores de Cisteína Proteinasa/análisis , Inhibidores de Cisteína Proteinasa/farmacología , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Hidrazonas , Células Madre Pluripotentes Inducidas/citología , Modelos Biológicos , Morfolinas/análisis , Morfolinas/farmacología , Pandemias , Pirimidinas , Reproducibilidad de los Resultados , SARS-CoV-2 , Bibliotecas de Moléculas Pequeñas/análisis , Bibliotecas de Moléculas Pequeñas/farmacología , Triazinas/análisis , Triazinas/farmacología , Internalización del Virus/efectos de los fármacos , Replicación Viral/efectos de los fármacos , Tratamiento Farmacológico de COVID-19
8.
Mol Cell ; 71(4): 637-648.e5, 2018 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-30118682

RESUMEN

Although macrophages are armed with potent antibacterial functions, Mycobacterium tuberculosis (Mtb) replicates inside these innate immune cells. Determinants of macrophage intrinsic bacterial control, and the Mtb strategies to overcome them, are poorly understood. To further study these processes, we used an affinity tag purification mass spectrometry (AP-MS) approach to identify 187 Mtb-human protein-protein interactions (PPIs) involving 34 secreted Mtb proteins. This interaction map revealed two factors involved in Mtb pathogenesis-the secreted Mtb protein, LpqN, and its binding partner, the human ubiquitin ligase CBL. We discovered that an lpqN Mtb mutant is attenuated in macrophages, but growth is restored when CBL is removed. Conversely, Cbl-/- macrophages are resistant to viral infection, indicating that CBL regulates cell-intrinsic polarization between antibacterial and antiviral immunity. Collectively, these findings illustrate the utility of this Mtb-human PPI map for developing a deeper understanding of the intricate interactions between Mtb and its host.


Asunto(s)
Proteínas Bacterianas/genética , VIH/genética , Interacciones Huésped-Patógeno , Mycobacterium tuberculosis/genética , Proteínas Proto-Oncogénicas c-cbl/genética , Factores de Virulencia/genética , Animales , Proteínas Bacterianas/inmunología , Línea Celular Tumoral , Chlamydia trachomatis/genética , Chlamydia trachomatis/inmunología , Regulación de la Expresión Génica , VIH/inmunología , Herpesvirus Humano 8/genética , Herpesvirus Humano 8/inmunología , Humanos , Linfocitos/microbiología , Linfocitos/virología , Macrófagos/microbiología , Macrófagos/virología , Ratones , Mycobacterium tuberculosis/inmunología , Cultivo Primario de Células , Unión Proteica , Mapeo de Interacción de Proteínas , Proteínas Proto-Oncogénicas c-cbl/deficiencia , Proteínas Proto-Oncogénicas c-cbl/inmunología , Células RAW 264.7 , Transducción de Señal , Factores de Virulencia/inmunología
9.
Development ; 149(11)2022 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-35695185

RESUMEN

In the developing subpallium, the fate decision between neurons and glia is driven by expression of Dlx1/2 or Olig1/2, respectively, two sets of transcription factors with a mutually repressive relationship. The mechanism by which Dlx1/2 repress progenitor and oligodendrocyte fate, while promoting transcription of genes needed for differentiation, is not fully understood. We identified a motif within DLX1 that binds RBBP4, a NuRD complex subunit. ChIP-seq studies of genomic occupancy of DLX1 and six different members of the NuRD complex show that DLX1 and NuRD colocalize to putative regulatory elements enriched near other transcription factor genes. Loss of Dlx1/2 leads to dysregulation of genome accessibility at putative regulatory elements near genes repressed by Dlx1/2, including Olig2. Consequently, heterozygosity of Dlx1/2 and Rbbp4 leads to an increase in the production of OLIG2+ cells. These findings highlight the importance of the interplay between transcription factors and chromatin remodelers in regulating cell-fate decisions.


Asunto(s)
Proteínas de Homeodominio , Complejo Desacetilasa y Remodelación del Nucleosoma Mi-2 , Diferenciación Celular/genética , Genes Homeobox , Proteínas de Homeodominio/metabolismo , Complejo Desacetilasa y Remodelación del Nucleosoma Mi-2/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
10.
Nature ; 569(7755): 270-274, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31043744

RESUMEN

Cancer immunotherapy restores or enhances the effector function of CD8+ T cells in the tumour microenvironment1,2. CD8+ T cells activated by cancer immunotherapy clear tumours mainly by inducing cell death through perforin-granzyme and Fas-Fas ligand pathways3,4. Ferroptosis is a form of cell death that differs from apoptosis and results from iron-dependent accumulation of lipid peroxide5,6. Although it has been investigated in vitro7,8, there is emerging evidence that ferroptosis might be implicated in a variety of pathological scenarios9,10. It is unclear whether, and how, ferroptosis is involved in T cell immunity and cancer immunotherapy. Here we show that immunotherapy-activated CD8+ T cells enhance ferroptosis-specific lipid peroxidation in tumour cells, and that increased ferroptosis contributes to the anti-tumour efficacy of immunotherapy. Mechanistically, interferon gamma (IFNγ) released from CD8+ T cells downregulates the expression of SLC3A2 and SLC7A11, two subunits of the glutamate-cystine antiporter system xc-, impairs the uptake of cystine by tumour cells, and as a consequence, promotes tumour cell lipid peroxidation and ferroptosis. In mouse models, depletion of cystine or cysteine by cyst(e)inase (an engineered enzyme that degrades both cystine and cysteine) in combination with checkpoint blockade synergistically enhanced T cell-mediated anti-tumour immunity and induced ferroptosis in tumour cells. Expression of system xc- was negatively associated, in cancer patients, with CD8+ T cell signature, IFNγ expression, and patient outcome. Analyses of human transcriptomes before and during nivolumab therapy revealed that clinical benefits correlate with reduced expression of SLC3A2 and increased IFNγ and CD8. Thus, T cell-promoted tumour ferroptosis is an anti-tumour mechanism, and targeting this pathway in combination with checkpoint blockade is a potential therapeutic approach.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Ferroptosis , Inmunoterapia , Neoplasias/inmunología , Neoplasias/terapia , Sistema de Transporte de Aminoácidos y+/metabolismo , Animales , Antígeno B7-H1/antagonistas & inhibidores , Línea Celular Tumoral , Cisteína/metabolismo , Femenino , Ferroptosis/efectos de los fármacos , Cadena Pesada de la Proteína-1 Reguladora de Fusión/metabolismo , Humanos , Interferón gamma/inmunología , Peroxidación de Lípido , Melanoma/genética , Melanoma/inmunología , Melanoma/metabolismo , Melanoma/terapia , Ratones , Neoplasias/metabolismo , Nivolumab/uso terapéutico , Especies Reactivas de Oxígeno/metabolismo , Resultado del Tratamiento
12.
Mol Cell Proteomics ; 22(5): 100541, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37019383

RESUMEN

Apolipoprotein (apo) E4 is the major genetic risk factor for Alzheimer's disease. While neurons generally produce a minority of the apoE in the central nervous system, neuronal expression of apoE increases dramatically in response to stress and is sufficient to drive pathology. Currently, the molecular mechanisms of how apoE4 expression may regulate pathology are not fully understood. Here, we expand upon our previous studies measuring the impact of apoE4 on protein abundance to include the analysis of protein phosphorylation and ubiquitylation signaling in isogenic Neuro-2a cells expressing apoE3 or apoE4. ApoE4 expression resulted in a dramatic increase in vasodilator-stimulated phosphoprotein (VASP) S235 phosphorylation in a protein kinase A (PKA)-dependent manner. This phosphorylation disrupted VASP interactions with numerous actin cytoskeletal and microtubular proteins. Reduction of VASP S235 phosphorylation via PKA inhibition resulted in a significant increase in filopodia formation and neurite outgrowth in apoE4-expressing cells, exceeding levels observed in apoE3-expressing cells. Our results highlight the pronounced and diverse impact of apoE4 on multiple modes of protein regulation and identify protein targets to restore apoE4-related cytoskeletal defects.


Asunto(s)
Enfermedad de Alzheimer , Apolipoproteína E4 , Actinas/metabolismo , Enfermedad de Alzheimer/metabolismo , Apolipoproteína E3/genética , Apolipoproteína E3/metabolismo , Apolipoproteína E4/genética , Apolipoproteína E4/metabolismo , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Fosforilación , Proteómica , Animales , Ratones
13.
J Infect Dis ; 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38356153

RESUMEN

As use of HIV integrase strand transfer inhibitors (INSTI) increases and formulations are being developed for maintenance therapies and chemoprophylaxis, assessing virus suppression under INSTI-based regimens in prevention-relevant biologic compartments, such as the male genital tract, is timely. We used cell-source marker virion immunocapture to examine amplification of particle RNA then assessed the phylogenetic relatedness of seminal and blood viral sequences from men with HIV who were prescribed INSTI-based regimens. Seminal plasma immunocaptures yielded amplifiable virion RNA from 13/24 (54%) men, and the sequences were primarily associated with markers indicative of macrophage and resident dendritic cell sources. Genetic distances were greatest (>2%) between seminal virions and circulating proviruses, pointing to ongoing low-level expression from tissue-resident cells. While the low levels in semen predict an improbable likelihood of transmission, viruses with large genetic distances are expressed under potent INSTI therapy and have implications for determining epidemiologic linkages if adherence is suboptimal.

14.
J Virol ; 97(4): e0181322, 2023 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-36943134

RESUMEN

Despite lacking a DNA intermediate, orthomyxoviruses complete their replication cycle in the nucleus and generate multiple transcripts by usurping the host splicing machinery. This biology results in dynamic changes of relative viral transcripts over time and dictates the replicative phase of the infection. Here, we demonstrate that the family of archaeal L7Ae proteins uniquely inhibit the splicing biology of influenza A virus, influenza B virus, and Salmon isavirus, revealing a common strategy utilized by Orthomyxoviridae members to achieve this dynamic. L7Ae-mediated inhibition of virus biology was lost with the generation of a splicing-independent strain of influenza A virus and attempts to select for an escape mutant resulted in variants that conformed to host splicing biology at significant cost to their overall fitness. As L7Ae recognizes conventional kink turns in various RNAs, these data implicate the formation of a similar structure as a shared strategy adopted by this virus family to coordinate their replication cycle. IMPORTANCE Here, we demonstrate that a family of proteins from archaea specifically inhibit this splicing biology of all tested members of the Orthomyxoviridae family. We show that this inhibition extends to influenza A virus, influenza B virus, and isavirus genera, while having no significant impact on the mammalian transcriptome or proteome. Attempts to generate an escape mutant against L7Ae-mediated inhibition resulted in mutations surrounding the viral splice sites and a significant loss of viral fitness. Together, these findings reveal a unique biology shared among diverse members of the Orthomyxoviridae family that may serve as a means to generate future universal therapeutics.


Asunto(s)
Proteínas Arqueales , Orthomyxoviridae , Empalme del ARN , Proteínas Arqueales/genética , Proteínas Arqueales/metabolismo , Orthomyxoviridae/fisiología , Empalme del ARN/fisiología , Humanos , Animales , Perros , Células Vero , Chlorocebus aethiops , Células A549 , Células HEK293 , Interacciones Microbiota-Huesped , Infecciones por Orthomyxoviridae/genética , Infecciones por Orthomyxoviridae/virología
15.
J Virol ; 97(2): e0160022, 2023 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-36757205

RESUMEN

Infection by Kaposi sarcoma-associated herpesvirus (KSHV) can cause severe consequences, such as cancers and lymphoproliferative diseases. Whole inactivated viruses (WIV) with chemically destroyed genetic materials have been used as antigens in several licensed vaccines. During KSHV productive replication, virus-like vesicles (VLVs) that lack capsids and viral genomes are generated along with virions. Here, we investigated the immunogenicity of KSHV VLVs produced from a viral mutant that was defective in capsid formation and DNA packaging. Mice immunized with adjuvanted VLVs generated KSHV-specific T cell and antibody responses. Neutralization of KSHV infection by the VLV immune serum was low but was markedly enhanced in the presence of the complement system. Complement-enhanced neutralization and complement deposition on KSHV-infected cells was dependent on antibodies targeting viral open reading frame 4 (ORF4). However, limited complement-mediated enhancement was detected in the sera of a small cohort of KSHV-infected humans which contained few neutralizing antibodies. Therefore, vaccination that induces antibody effector functions can potentially improve infection-induced humoral immunity. Overall, our study highlights a potential benefit of engaging complement-mediated antibody functions in future KSHV vaccine development. IMPORTANCE KSHV is a virus that can lead to cancer after infection. A vaccine that prevents KSHV infection or transmission would be helpful in preventing the development of these cancers. We investigated KSHV VLV as an immunogen for vaccination. We determined that antibodies targeting the viral protein ORF4 induced by VLV immunization could engage the complement system and neutralize viral infection. However, ORF4-specific antibodies were seldom detected in the sera of KSHV-infected humans. Moreover, these human sera did not potently trigger complement-mediated neutralization, indicating an improvement that immunization can confer. Our study suggests a new antibody-mediated mechanism to control KSHV infection and underscores the benefit of activating the complement system in a future KSHV vaccine.


Asunto(s)
Anticuerpos Neutralizantes , Herpesvirus Humano 8 , Animales , Humanos , Ratones , Anticuerpos Neutralizantes/inmunología , Infecciones por Herpesviridae , Herpesvirus Humano 8/inmunología , Sistemas de Lectura Abierta/inmunología , Vacunación , Proteínas Virales/inmunología
16.
J Urol ; 211(3): 445-454, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38134235

RESUMEN

PURPOSE: There are limited data on ablation effects of thulium fiber laser (TFL) settings with varying stone composition. Similarly, little is known surrounding the photothermal effects of TFL lithotripsy regarding the chemical and structural changes after visible char formation. We aim to understand the TFL's ablative efficiency across various stone types and laser settings, while simultaneously investigating the photothermal effects of TFL lithotripsy. MATERIALS AND METHODS: Human specimens of calcium oxalate monohydrate, calcium oxalate dihydrate, uric acid, struvite, cystine, carbonate apatite, and brushite stones were ablated using 13 prespecified settings with the Coloplast TFL Drive. Pre- and postablation mass, ablation time, and total energy were recorded. Qualitative ablative observations were recorded at 1-minute intervals with photographs and gross description. Samples were analyzed with Fourier-transform infrared spectroscopy pre- and postablation and electron microscopy postablation to assess the photothermal effects of TFL. RESULTS: Across all settings and stone types, 0.05 J × 1000 Hz was the best numerically efficient ablation setting. When selected for more clinically relevant laser settings (ie, 10-20 W), 0.2 J × 100 Hz, short pulse was the most numerically efficient setting for calcium oxalate dihydrate, cystine, and struvite stones. Calcium oxalate monohydrate ablated with the best numerical efficiency at 0.4 J × 40 Hz, short pulse. Uric acid and carbonate apatite stones ablated with the best numerical efficiency at 0.3 J × 60 Hz, short pulse. Brushite stones ablated with the best numerical efficiency at 0.5 J × 30 Hz, short pulse. Pulse duration impacted ablation effectiveness greatly with 6/8 (75%) of inadequate ablations occurring in medium or long pulse settings. The average percent of mass lost during ablation was 57%; cystine stones averaged the highest percent mass lost at 71%. Charring was observed in 36/91 (40%) specimens. Charring was most often seen in uric acid, cystine, and brushite stones across all laser settings. Electron microscopy of char demonstrated a porous melting effect different to that of brittle fracture. Fourier-transform infrared spectroscopy of brushite char demonstrated a chemical composition change to amorphous calcium phosphate. CONCLUSIONS: We describe the optimal ablation settings based on stone composition, which may guide urologists towards more stone-specific care when using thulium laser for treating renal stones (lower energy settings would be safer for ureteral stones). For patients with unknown stone composition, lasers can be preset to target common stone types or adjusted based on visual cues. We recommend using short pulse for all TFL lithotripsy of calculi and altering the settings based on visual cues and efficiency to minimize the charring, an effect which can make the stone refractory to further dusting and fragmentation.


Asunto(s)
Apatitas , Fosfatos de Calcio , Cálculos Renales , Láseres de Estado Sólido , Litotripsia por Láser , Cálculos Urinarios , Humanos , Cálculos Urinarios/cirugía , Cálculos Urinarios/química , Tulio/química , Estruvita , Cistina , Ácido Úrico , Cálculos Renales/terapia , Rayos Láser , Litotripsia por Láser/métodos , Láseres de Estado Sólido/uso terapéutico
17.
Ann Surg Oncol ; 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38955992

RESUMEN

BACKGROUND: Immediate lymphatic reconstruction (ILR) has been proposed to decrease lymphedema rates. The primary aim of our study was to determine whether ILR decreased the incidence of lymphedema in patients undergoing axillary lymph node dissection (ALND). METHODS: We conducted a two-site pragmatic study of ALND with or without ILR, employing surgeon-level cohort assignment, based on breast surgeons' preferred standard practice. Lymphedema was assessed by limb volume measurements, patient self-reporting, provider documentation, and International Classification of Diseases, Tenth Revision (ICD-10) codes. RESULTS: Overall, 230 patients with breast cancer were enrolled; on an intention-to-treat basis, 99 underwent ALND and 131 underwent ALND with ILR. Of the 131 patients preoperatively planned for ILR, 115 (87.8%) underwent ILR; 72 (62.6%) were performed by one breast surgical oncologist and 43 (37.4%) by fellowship-trained microvascular plastic surgeons. ILR was associated with an increased risk of lymphedema when defined as ≥10% limb volume change on univariable analysis, but not on multivariable analysis, after propensity score adjustment. We did not find a statistically significant difference in limb volume measurements between the two cohorts when including subclinical lymphedema (≥5% inter-limb volume change), nor did we see a difference in grade between the two cohorts on an intent-to-treat or treatment received basis. For all patients, considering ascertainment strategies of patient self-reporting, provider documentation, and ICD-10 codes, as a single binary outcome measure, there was no significant difference in lymphedema rates between those undergoing ILR or not. CONCLUSION: We found no significant difference in lymphedema rates between patients undergoing ALND with or without ILR.

18.
J Gen Intern Med ; 39(8): 1414-1422, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38148474

RESUMEN

BACKGROUND: The FDA issued a "black box" warning regarding risks of fluoroquinolones in 2008 with updates in 2011, 2013, and 2016. OBJECTIVE: To examine antimicrobial use in hospital-treated UTIs from 2000 to 2020. DESIGN: Cross-sectional study with interrupted time series analysis. PARTICIPANTS: Patient encounters with a diagnosis of UTI from January 2000 to March 2020, excluding diagnoses of renal abscess, chronic cystitis, and infection of the gastrointestinal tract, lungs, or prostate. MAIN MEASURES: Monthly use of fluoroquinolone and non-fluoroquinolone antibiotics were assessed. Fluoroquinolone resistance was assessed in available cultures. Interrupted time series analysis examined level and trend changes of antimicrobial use with each FDA label change. KEY RESULTS: A total of 9,950,790 patient encounters were included. From July 2008 to March 2020, fluoroquinolone use declined from 61.7% to 11.7%, with similar negative trends observed in inpatients and outpatients, age ≥ 60 and < 60 years, males and females, patients with and without pyelonephritis, and across physician specialties. Ceftriaxone use increased from 26.4% encounters in July 2008 to 63.6% of encounters in March 2020. Among encounters with available culture data, fluoroquinolone resistance declined by 28.9% from 2009 to 2020. On interrupted time series analysis, the July 2008 FDA warning was associated with a trend change (-0.32%, < 0.001) and level change (-5.02%, p < 0.001) in monthly fluoroquinolone use. CONCLUSIONS: During this era of "black box" warnings, there was a decline in fluoroquinolone use for hospital-treated UTI with a concomitant decline in fluoroquinolone resistance and rise in ceftriaxone use. Efforts to restrict use of a medication class may lead to compensatory increases in use of a single alternative agent with changes in antimicrobial resistance profiles.


Asunto(s)
Antibacterianos , United States Food and Drug Administration , Infecciones Urinarias , Humanos , Infecciones Urinarias/tratamiento farmacológico , Masculino , Femenino , Estados Unidos/epidemiología , Estudios Transversales , Antibacterianos/uso terapéutico , Antibacterianos/efectos adversos , Persona de Mediana Edad , Anciano , Adulto , Fluoroquinolonas/uso terapéutico , Análisis de Series de Tiempo Interrumpido , Infección Hospitalaria/tratamiento farmacológico , Infección Hospitalaria/epidemiología
19.
Diabetes Obes Metab ; 26(4): 1244-1251, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38131246

RESUMEN

AIM: To characterize the impact of the COVID-19 pandemic on diabetes diagnosis using data from Alberta's Tomorrow Project (ATP), a population-based cohort study of chronic diseases in Alberta, Canada. MATERIALS AND METHODS: The ATP participants who were free of diabetes on 1 April 2018 were included in the study. A time-segmented regression model was used to compare incidence rates of diabetes before the COVID-19 pandemic, during the first two COVID-19 states of emergency, and in the period when the state of emergency was relaxed, after adjusting for seasonality, sociodemographic factors, socioeconomic status, and lifestyle behaviours. RESULTS: Among 43 705 ATP participants free of diabetes (65.5% females, age 60.4 ± 9.5 years in 2018), the rate of diabetes was 4.75 per 1000 person-year (PY) during the COVID-19 pandemic (up to 31 March 2021), which was 32% lower (95% confidence interval [CI] 21%, 42%; p < 0.001) than pre-pandemic (6.98 per 1000 PY for the period 1 April 2018 to 16 March 2020). In multivariable regression analysis, the first COVID-19 state of emergency (first wave) was associated with an 87.3% (95% CI -98.6%, 13.9%; p = 0.07) reduction in diabetes diagnosis; this decreasing trend was sustained to the second COVID-19 state of emergency and no substantial rebound (increase) was observed when the COVID-19 state of emergency was relaxed. CONCLUSIONS: The COVID-19 public health emergencies had a negative impact on diabetes diagnosis in Alberta. The reduction in diabetes diagnosis was likely due to province-wide health service disruptions during the COVID-19 pandemic. Systematic plans to close the post-COVID-19 diagnostic gap are required in diabetes to avoid substantial downstream sequelae of undiagnosed disease.


Asunto(s)
COVID-19 , Diabetes Mellitus , Femenino , Humanos , Persona de Mediana Edad , Anciano , Masculino , Estudios de Cohortes , Estudios Longitudinales , Incidencia , Pandemias/prevención & control , Alberta/epidemiología , COVID-19/epidemiología , Diabetes Mellitus/epidemiología , Adenosina Trifosfato
20.
J Org Chem ; 89(8): 5878-5882, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38501591

RESUMEN

Michael-aldol domino reactions are powerful tools for rapidly assembling carbocyclic scaffolds. We herein disclose a base-catalyzed Michael-aldol domino reaction of trisubstituted Michael acceptors with ß-keto ester nucleophiles. The cyclohexanone products are obtained in excellent diastereoselectivity (up to >20:1 dr) and good yields (up to 84%). An attractive practical consideration is that pure products are isolated directly via filtration of the unpurified reaction mixtures. Further functionalization of the cyclohexanones is achieved without perturbation of stereocenters installed through the preceding annulation.

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