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1.
Nature ; 609(7928): 785-792, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35922005

RESUMEN

Highly pathogenic coronaviruses, including severe acute respiratory syndrome coronavirus 2 (refs. 1,2) (SARS-CoV-2), Middle East respiratory syndrome coronavirus3 (MERS-CoV) and SARS-CoV-1 (ref. 4), vary in their transmissibility and pathogenicity. However, infection by all three viruses results in substantial apoptosis in cell culture5-7 and in patient tissues8-10, suggesting a potential link between apoptosis and pathogenesis of coronaviruses. Here we show that caspase-6, a cysteine-aspartic protease of the apoptosis cascade, serves as an important host factor for efficient coronavirus replication. We demonstrate that caspase-6 cleaves coronavirus nucleocapsid proteins, generating fragments that serve as interferon antagonists, thus facilitating virus replication. Inhibition of caspase-6 substantially attenuates lung pathology and body weight loss in golden Syrian hamsters infected with SARS-CoV-2 and improves the survival of mice expressing human DPP4 that are infected with mouse-adapted MERS-CoV. Our study reveals how coronaviruses exploit a component of the host apoptosis cascade to facilitate virus replication.


Asunto(s)
Ácido Aspártico , Caspasa 6 , Infecciones por Coronavirus , Coronavirus , Cisteína , Interacciones Huésped-Patógeno , Replicación Viral , Animales , Apoptosis , Ácido Aspártico/metabolismo , Caspasa 6/metabolismo , Coronavirus/crecimiento & desarrollo , Coronavirus/patogenicidad , Infecciones por Coronavirus/enzimología , Infecciones por Coronavirus/virología , Proteínas de la Nucleocápside de Coronavirus/inmunología , Proteínas de la Nucleocápside de Coronavirus/metabolismo , Cricetinae , Cisteína/metabolismo , Dipeptidil Peptidasa 4/genética , Dipeptidil Peptidasa 4/metabolismo , Humanos , Interferones/antagonistas & inhibidores , Interferones/inmunología , Pulmón/patología , Mesocricetus , Ratones , Coronavirus del Síndrome Respiratorio de Oriente Medio , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , SARS-CoV-2 , Tasa de Supervivencia , Pérdida de Peso
2.
Nature ; 603(7902): 693-699, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35062016

RESUMEN

The Omicron (B.1.1.529) variant of SARS-CoV-2 emerged in November 2021 and is rapidly spreading among the human population1. Although recent reports reveal that the Omicron variant robustly escapes vaccine-associated and therapeutic neutralization antibodies2-10, the pathogenicity of the virus remains unknown. Here we show that the replication of Omicron is substantially attenuated in human Calu3 and Caco2 cells. Further mechanistic investigations reveal that Omicron is inefficient in its use of transmembrane serine protease 2 (TMPRSS2) compared with wild-type SARS-CoV-2 (HKU-001a) and previous variants, which may explain its reduced replication in Calu3 and Caco2 cells. The replication of Omicron is markedly attenuated in both the upper and lower respiratory tracts of infected K18-hACE2 mice compared with that of the wild-type strain and Delta (B.1.617.2) variant, resulting in its substantially ameliorated lung pathology. Compared with wild-type SARS-CoV-2 and the Alpha (B.1.1.7), Beta (1.351) and Delta variants, infection by Omicron causes the lowest reduction in body weight and the lowest mortality rate. Overall, our study demonstrates that the replication and pathogenicity of the Omicron variant of SARS-CoV-2 in mice is attenuated compared with the wild-type strain and other variants.


Asunto(s)
COVID-19/patología , COVID-19/virología , SARS-CoV-2/patogenicidad , Replicación Viral , Enzima Convertidora de Angiotensina 2/genética , Enzima Convertidora de Angiotensina 2/metabolismo , Animales , COVID-19/inmunología , Células CACO-2 , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , SARS-CoV-2/inmunología , SARS-CoV-2/metabolismo , Serina Endopeptidasas/metabolismo , Virulencia
3.
Proc Natl Acad Sci U S A ; 119(29): e2201169119, 2022 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-35858300

RESUMEN

Protein kinase R (PKR) is a critical host restriction factor against invading viral pathogens. However, this molecule is inactivated in the cells infected with porcine reproductive and respiratory syndrome virus (PRRSV), an economically devastating pathogen to the world swine industry. Here, we report that this event is to suppress cellular inflammation and is mediated by the viral replicase protein nsp1ß. We show that nsp1ß is a stress-responsive protein, enters virus-induced stress granules (SGs) during infection, and repurposes SGs into a proviral platform, where it co-opts the SG core component G3BP1 to interact with PKR in a regulated manner. RNA interference silencing of G3BP1 or mutation of specific nsp1ß residues (VS19GG) can abolish the antagonization of PKR activation. The viral mutant carrying the corresponding mutations induces elevated level of PKR phosphorylation and pronounced production of inflammatory cytokines (e.g., tumor necrosis factor-α, interleukin [IL]-6, and IL-8), whereas small-interfering RNA knockdown of PKR or treatment with C16, a PKR inhibitor, blocks this effect. Thus, PRRSV has evolved a unique strategy to evade PKR restriction to suppress host inflammatory responses.


Asunto(s)
Factores de Restricción Antivirales , ADN Helicasas , Evasión Inmune , Proteínas de Unión a Poli-ADP-Ribosa , Virus del Síndrome Respiratorio y Reproductivo Porcino , ARN Helicasas , Proteínas con Motivos de Reconocimiento de ARN , Gránulos de Estrés , Proteínas no Estructurales Virales , eIF-2 Quinasa , Animales , Factores de Restricción Antivirales/metabolismo , ADN Helicasas/metabolismo , Proteínas de Unión a Poli-ADP-Ribosa/metabolismo , Virus del Síndrome Respiratorio y Reproductivo Porcino/genética , Virus del Síndrome Respiratorio y Reproductivo Porcino/metabolismo , ARN Helicasas/metabolismo , Proteínas con Motivos de Reconocimiento de ARN/metabolismo , Gránulos de Estrés/virología , Porcinos , Proteínas no Estructurales Virales/metabolismo , Replicación Viral , eIF-2 Quinasa/metabolismo
4.
J Med Virol ; 96(2): e29472, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38373201

RESUMEN

Interferons (IFNs) are critical for immune defense against pathogens. While type-I and -III IFNs have been reported to inhibit SARS-CoV-2 replication, the antiviral effect and mechanism of type-II IFN against SARS-CoV-2 remain largely unknown. Here, we evaluate the antiviral activity of type-II IFN (IFNγ) using human lung epithelial cells (Calu3) and ex vivo human lung tissues. In this study, we found that IFNγ suppresses SARS-CoV-2 replication in both Calu3 cells and ex vivo human lung tissues. Moreover, IFNγ treatment does not significantly modulate the expression of SARS-CoV-2 entry-related factors and induces a similar level of pro-inflammatory response in human lung tissues when compared with IFNß treatment. Mechanistically, we show that overexpression of indoleamine 2,3-dioxygenase 1 (IDO1), which is most profoundly induced by IFNγ, substantially restricts the replication of ancestral SARS-CoV-2 and the Alpha and Delta variants. Meanwhile, loss-of-function study reveals that IDO1 knockdown restores SARS-CoV-2 replication restricted by IFNγ in Calu3 cells. We further found that the treatment of l-tryptophan, a substrate of IDO1, partially rescues the IFNγ-mediated inhibitory effect on SARS-CoV-2 replication in both Calu3 cells and ex vivo human lung tissues. Collectively, these results suggest that type-II IFN potently inhibits SARS-CoV-2 replication through IDO1-mediated antiviral response.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/metabolismo , Indolamina-Pirrol 2,3,-Dioxigenasa/genética , Replicación Viral , Pulmón , Interferones , Células Epiteliales , Antivirales/farmacología
5.
BMC Cancer ; 24(1): 877, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39039516

RESUMEN

BACKGROUND: Inetetamab is the first domestically developed innovative anti-HER2 monoclonal antibody in China, proven effective and safe in HER2-positive advanced breast cancer. However, its efficacy and safety in neoadjuvant treatment of HER2-positive locally advanced breast cancer (LABC) remain to be validated. METHODS: This prospective cohort study aimed to evaluate the efficacy and safety of inetetamab combined with pertuzumab, taxanes, and carboplatin (TCbIP) in neoadjuvant therapy for HER2-positive LABC, comparing it to data from patients treated with the TCbHP regimen (trastuzumab combined with pertuzumab, taxanes, and carboplatin) using propensity score matching (PSM). The primary endpoint was total pathological complete response (tpCR). Adverse events (AEs), objective response rate (ORR), and near-pCR were key secondary endpoints. RESULTS: Forty-four patients with clinical stage IIA-IIIC HER2-positive LABC were prospectively enrolled and treated with the TCbIP regimen. The tpCR rate among 28 patients who completed surgery was 60.7%, comparable to and slightly higher than the TCbHP group in PSM (60.7% vs. 53.6%, P = 0.510). The ORR was 96.4%, and the DCR reached 100.0%. The most common ≥ grade 3 AE was neutropenia (21.4% vs. 11.9%, P = 0.350). No significant reduction in left ventricular ejection fraction was observed, and no patient withdrew from treatment due to AEs. CONCLUSION: Neoadjuvant therapy with TCbIP showed good efficacy and safety in patients with HER2-positive LABC and might be another promising option for neoadjuvant treatment. TRIAL REGISTRATION: NCT05749016 (registration date: Nov 01, 2021).


Asunto(s)
Anticuerpos Monoclonales Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias de la Mama , Carboplatino , Terapia Neoadyuvante , Puntaje de Propensión , Receptor ErbB-2 , Taxoides , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Neoplasias de la Mama/metabolismo , Carboplatino/administración & dosificación , Carboplatino/uso terapéutico , Persona de Mediana Edad , Terapia Neoadyuvante/métodos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Estudios Prospectivos , Adulto , Receptor ErbB-2/metabolismo , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales Humanizados/administración & dosificación , Taxoides/administración & dosificación , Taxoides/uso terapéutico , Anciano , Trastuzumab/uso terapéutico , Trastuzumab/administración & dosificación , Resultado del Tratamiento
6.
Ann Hematol ; 103(1): 163-174, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37817010

RESUMEN

The present study aimed to investigate the clinical features, prognosis, and treatment of advanced-stage non-nasal type extranodal natural killer/T-cell lymphoma (ENKTCL). This real-world study retrospectively reviewed 56 newly diagnosed advanced-stage non-nasal type ENKTCL patients from two large-scale Chinese cancer centers in the last 10-15 years and screened 139 newly diagnosed advanced-stage nasal type ENKTCLs admitted during the same period for comparison. The non-nasal type ENKTCLs exhibited significantly higher Ki-67 expression levels compared to nasal type disease (P = 0.011). With a median follow-up duration of 75.03 months, the non-nasal group showed slightly inferior survival outcomes without statistically significant differences compared to the nasal group (median overall survival (OS): 14.57 vs. 21.53 months, 5-year OS: 28.0% vs. 38.5%, P = 0.120). Eastern Cooperative Oncology Group (ECOG) score ≥ 2 (hazard ratio (HR) = 2.18, P = 0.039) and lactic dehydrogenase (LDH) elevation (HR = 2.44, P = 0.012) were significantly correlated with worse OS in the non-nasal group. First-line gemcitabine-based chemotherapy regimens showed a trend toward slightly improved efficacy and survival outcomes compared to non-gemcitabine-based ones in the present cohort of non-nasal ENKTCLs (objective response rate: 91.7% vs. 63.6%, P = 0.144; complete response rate: 50.0% vs. 33.3%, P = 0.502; median progression-free survival: 10.43 vs. 3.40 months, P = 0.106; median OS: 25.13 vs. 9.30 months, P = 0.125), which requires further validation in larger sample size studies. Advanced-stage non-nasal type patients could achieve comparable prognosis with nasal cases after rational therapy. The modified nomogram-revised index (including age, ECOG score, and LDH) and modified international prognostic index (including age, ECOG score, LDH, and number of extranodal involvement) functioned effectively for prognostic stratification in non-nasal type ENKTCLs.


Asunto(s)
Linfoma Extranodal de Células NK-T , Linfoma de Células T , Humanos , Pronóstico , Estudios Retrospectivos , Modelos de Riesgos Proporcionales , Células Asesinas Naturales/patología , Linfoma de Células T/patología , Linfoma Extranodal de Células NK-T/diagnóstico , Linfoma Extranodal de Células NK-T/tratamiento farmacológico , Estadificación de Neoplasias
7.
Artículo en Inglés | MEDLINE | ID: mdl-38439666

RESUMEN

Myocardial ischemia/reperfusion (I/R) injury is a classic type of cardiovascular disease characterized by injury to cardiomyocytes leading to different types of cell death. The degree of irreversible myocardial damage is closely related to age, and ferroptosis is involved in cardiomyocyte damage. However, the mechanisms underlying ferroptosis regulation in aging myocardial I/R injury are still unclear. The present study aims to explore the underlying mechanism of piRNA regulation in ferroptosis. Using left anterior descending coronary artery ligation in an aging rat model and a D-galactose-induced rat cardiomyocyte line (H9C2) to construct an aging cardiomyocyte model, we investigate whether ferroptosis occurs after reperfusion injury in vitro and in vivo. This study focuses on the upregulation of piR-000699 after hypoxia/reoxygenation treatment in aging cardiomyocytes by observing hypoxia/reoxygenation (H/R) injury indicators and ferroptosis-related indicators and clarifying the role of piR-000699 in H/R injury caused by ferroptosis in aging cardiomyocytes. Bioinformatics analysis reveals that SLC39A14 is a gene that binds to piR-000699. Our data show that ferroptosis plays an important role in I/R injury both in vivo and in vitro. Furthermore, the results show the potential role of piR-000699 in regulating SLC39A14 in ferroptosis in aging cardiomyocytes under hypoxia/reoxygenation conditions. Together, our results reveal that the mechanism by which piR-000699 binds to SLC39A14 regulates ferroptosis in aging myocardial I/R injury.

8.
Int J Cancer ; 153(9): 1643-1657, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37539660

RESUMEN

The study investigated the treatment and prognosis of advanced-stage extranodal natural killer/T-cell lymphoma (ENKTL). With a median follow-up of 75.03 months, the median overall survival (mOS) for the 195 newly diagnosed stage III/IV ENKTL patients was 19.43 months, and estimated 1-, 2-, 3- and 5-year OS were 59.5%, 46.3%, 41.8% and 35.1%, respectively. Chemotherapy (CT) + radiotherapy (RT) compared to CT alone (P = .007), and hematopoietic stem cell transplantation (HSCT) compared to non-HSCT (P < .001), both improved OS. For patients ≤60 years and ineligible for HSCT, other therapies with complete remission led to comparable OS (P = .141). Nine patients ever treated with chidamide achieved a median progression-free survival (mPFS) and mOS of 53.63 (range, 3.47-92.33) and 54.80 (range, 5.50-95.70) months, and four with chidamide maintenance therapy (MT) achieved a mPFS and mOS of 55.83 (range, 53.27-92.33) and 60.65 (range, 53.70-95.70) months, possibly providing an alternative option for non-HSCT patients. Non-anthracycline (ANT)- compared to ANT-, asparaginase (Aspa)- compared to non-Aspa- and gemcitabine (Gem)- compared to non-Gem-based regimens, prolonged PFS (P = .031; P = .005; P = .009) and OS (P = .010; P = .086; P = .003), respectively. Multivariate analysis demonstrated that Gem-based regimens improved PFS (HR = 0.691, P = .061) and OS (HR = 0.624, P = .037). Gem + Aspa combinations slightly improved PFS and OS compared to regimens containing Gem or Aspa alone (P > 0.05). First-line "intensive therapy," including CT (particularly Gem + Aspa regimens), RT, HSCT and alternative chidamide MT, was proposed and could improve long-term survival for advanced-stage ENKTLs. Ongoing prospective clinical studies may shed further light on the value of chidamide MT.


Asunto(s)
Linfoma Extranodal de Células NK-T , Humanos , Linfoma Extranodal de Células NK-T/tratamiento farmacológico , Estudios Prospectivos , Aminopiridinas , Benzamidas/uso terapéutico , Asparaginasa , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Gemcitabina , Antraciclinas/uso terapéutico , Estudios Retrospectivos
9.
Chemotherapy ; 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-37984344

RESUMEN

INTRODUCTION: Although there is now a consensus on asparaginase-based chemotherapy regimens in treatment of advanced-stage extranodal natural killer / T cell lymphomas (ENKTCLs), patient survival in the real-world setting is still not optimistic according to previous literature reports, and the optimal chemotherapeutic regimens and integration of different therapeutic methods under the concept of combined-modality treatment still need to be further explored and verified. METHODS: Newly diagnosed stage Ⅲ / Ⅳ ENKTCL patients from Chinese National Cancer Center in the last two decades were retrospectively collected and analyzed. Overall survival (OS) and progression-free survival (PFS) were determined as primary endpoints. Log-rank tests and Cox proportional hazard models were performed to test for survival differences between subgroups and examine the univariable and multivariable associations. RESULTS: The study included 83 newly diagnosed stage Ⅲ / Ⅳ ENKTCL patients and reported a median OS of 26.07 months and an estimated 5-year OS of 41.3% with a median follow-up of 82.13 months. First-line asparaginase- compared to non-asparaginase-based regimens significantly prolonged PFS (P=0.007; HR=0.48, P=0.020) and showed a tendency to improve OS (P=0.064; HR=0.74, P=0.359). Gemcitabine-based regimens also exhibited a trend towards improved PFS (P=0.048; HR=0.59, P=0.164) and OS (P=0.008; HR=0.67, P=0.282) compared to non-gemcitabine-based ones. The asparaginase and gemcitabine combinations yielded a 5-year OS of 55.0% and led to significantly superior PFS (P=0.020; HR=0.40, P=0.022) and slightly better OS (P=0.054; HR=0.79, P=0.495) compared to the remaining regimens. First-line combined-modality treatment integrating chemotherapy and radiotherapy improved PFS (P=0.051) and OS (P=0.036) compared to chemotherapy alone. Four autologous hematopoietic stem cell transplantation recipients reached a median OS of 58.34 months. CONCLUSION: Asparaginase and gemcitabine alone brought favorable impact on PFS and OS; and the asparaginase and gemcitabine combination chemotherapy yielded the optimal efficacy, response duration and survival outcomes. Combined-modality treatment including potent chemotherapy supplemented by radiotherapy and/or consolidative transplantation could improve prognosis in newly diagnosed advanced-stage ENKTCLs.

10.
Clin Infect Dis ; 75(1): e1101-e1111, 2022 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-34536277

RESUMEN

BACKGROUND: The effect of low environmental temperature on viral shedding and disease severity of Coronavirus Disease 2019 (COVID-19) is uncertain. METHODS: We investigated the virological, clinical, pathological, and immunological changes in hamsters housed at room (21°C), low (12-15°C), and high (30-33°C) temperature after challenge by 105 plaque-forming units of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). RESULTS: The nasal turbinate, trachea, and lung viral load and live virus titer were significantly higher (~0.5-log10 gene copies/ß-actin, P < .05) in the low-temperature group at 7 days postinfection (dpi). The low-temperature group also demonstrated significantly higher level of tumor necrosis factor-α, interferon-γ (IFN-γ), interleukin-1ß, and C-C motif chemokine ligand 3, and lower level of the antiviral IFN-α in lung tissues at 4 dpi than the other 2 groups. Their lungs were grossly and diffusely hemorrhagic, with more severe and diffuse alveolar and peribronchiolar inflammatory infiltration, bronchial epithelial cell death, and significantly higher mean total lung histology scores. By 7 dpi, the low-temperature group still showed persistent and severe alveolar inflammation and hemorrhage, and little alveolar cell proliferative changes of recovery. The viral loads in the oral swabs of the low-temperature group were significantly higher than those of the other two groups from 10 to 17 dpi by about 0.5-1.0 log10 gene copies/ß-actin. The mean neutralizing antibody titer of the low-temperature group was significantly (P < .05) lower than that of the room temperature group at 7 dpi and 30 dpi. CONCLUSIONS: This study provided in vivo evidence that low environmental temperature exacerbated the degree of virus shedding, disease severity, and tissue proinflammatory cytokines/chemokines expression, and suppressed the neutralizing antibody response of SARS-CoV-2-infected hamsters. Keeping warm in winter may reduce the severity of COVID-19.


Asunto(s)
COVID-19 , Actinas , Animales , Anticuerpos Neutralizantes , Cricetinae , Modelos Animales de Enfermedad , Humanos , Pulmón , Mesocricetus , SARS-CoV-2 , Temperatura
11.
Ann Hematol ; 101(9): 2021-2034, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35798977

RESUMEN

The present study investigated the efficacy and toxicity profile of first-line asparaginase (ASP)-based versus non-ASP-based regimens in treating early-stage extranodal NK/T-cell lymphoma (ENKTCL) in non-anthracycline therapy era. This multi-center, real-world retrospective study consisted 305 newly diagnosed localized ENKTCL patients who were treated with sequential chemoradiation between 2010 and 2020 in China: 190 cases received ASP-based regimens and 115 cases received non-ASP-based regimens. Propensity score matching and multivariable analyses were used to compare survivals and toxicities between the two treatment groups. Non-ASP-based regimens achieved comparable survivals compared with ASP-based regimens in the entire cohort. The 5-year overall survival (OS), progression-free survival (PFS) rates were 84.7% and 73.5% for non-ASP-based regimens, and 87.7% (P=0.464) and 74.6% (P=0.702) for ASP-based regimens. The non-inferior survivals of non-ASP-based regimens were consistent after adjustment using PSM and multivariable analyses. However, survival benefits of ASP varied in different treatment modalities. Among patients receiving sequential chemotherapy and radiation (CT+RT±CT), ASP-based regimens achieved higher complete remission rate (54.3 vs. 34.5%, P=0.047) and more favorable survivals compared with non-ASP-based regimens (5-year OS, 87.0 vs. 69.0%, P=0.028). However, for patients receiving sequential radiation and chemotherapy (RT+CT), non-ASP-based regimens achieved comparable favorable survivals as ASP-based regimens. Besides, liver injury, malnutrition, and coagulative dysfunction were significantly more commonly documented in ASP-based regimens. These findings suggested that ASP was an effective agent in treating ENKTCL, especially among those receiving induction CT and RT. For patients who received upfront RT, non-ASP-based regimens might be a comparably effective and more tolerable treatment option.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Linfoma Extranodal de Células NK-T , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Quimioradioterapia , Humanos , Linfoma Extranodal de Células NK-T/diagnóstico , Linfoma Extranodal de Células NK-T/tratamiento farmacológico , Linfoma Extranodal de Células NK-T/radioterapia , Inducción de Remisión , Estudios Retrospectivos
12.
PLoS Pathog ; 15(11): e1008169, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31738790

RESUMEN

The unfolded protein response (UPR) in the endoplasmic reticulum (ER) constitutes a critical component of host innate immunity against microbial infections. In this report, we show that porcine reproductive and respiratory syndrome virus (PRRSV) utilizes the UPR machinery for its own benefit. We provide evidence that the virus targets the UPR central regulator GRP78 for proteasomal degradation via a mechanism that requires viral glycoprotein GP2a, while both IRE1-XBP1s and PERK-eIF2α-ATF4 signaling branches of the UPR are turned on at early stage of infection. The activated effector XBP1s was found to enter the nucleus, but ATF4 was unexpectedly diverted to cytoplasmic viral replication complexes by means of nonstructural proteins nsp2/3 to promote viral RNA synthesis. RNAi knockdown of either ATF4 or XBP1s dramatically attenuated virus titers, while overexpression caused increases. These observations reveal attractive host targets (e.g., ATF4 and XBP1s) for antiviral drugs and have implications in vaccine development.


Asunto(s)
Retículo Endoplásmico/virología , Síndrome Respiratorio y de la Reproducción Porcina/virología , Virus del Síndrome Respiratorio y Reproductivo Porcino/fisiología , Respuesta de Proteína Desplegada , Replicación Viral , eIF-2 Quinasa/metabolismo , Factor de Transcripción Activador 4/genética , Factor de Transcripción Activador 4/metabolismo , Animales , Retículo Endoplásmico/metabolismo , Chaperón BiP del Retículo Endoplásmico , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Síndrome Respiratorio y de la Reproducción Porcina/genética , Síndrome Respiratorio y de la Reproducción Porcina/metabolismo , Transducción de Señal , Porcinos , Proteína 1 de Unión a la X-Box/genética , Proteína 1 de Unión a la X-Box/metabolismo , eIF-2 Quinasa/genética
13.
Opt Express ; 29(24): 40231-40239, 2021 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-34809369

RESUMEN

We numerically study photo-induced waveguides using a single Bessel beam in a photorefractive (PR) medium. Under self-focusing nonlinearity, we demonstrate the possibility for creating complex waveguiding structures with multiple input/output channels. The truncation of the incoming Bessel beam, the nonlinearity of the PR medium, the light intensity, and the order and the size of the Bessel beam are the key parameters for achieving different configurations with high guiding efficiencies. As such, not only classical X or Y couplers but also more complex structures can be generated with up to 7 identified inputs/outputs. These results provide large opportunities for all-optical interconnects.

14.
J Infect Dis ; 222(5): 734-745, 2020 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-32563187

RESUMEN

Clinical manifestations of coronavirus disease 2019 (COVID-19) vary from asymptomatic virus shedding, nonspecific pharyngitis, to pneumonia with silent hypoxia and respiratory failure. Dendritic cells and macrophages are sentinel cells for innate and adaptive immunity that affect the pathogenesis of severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). The interplay between SARS-CoV-2 and these cell types remains unknown. We investigated infection and host responses of monocyte-derived dendritic cells (moDCs) and macrophages (MDMs) infected by SARS-CoV-2. MoDCs and MDMs were permissive to SARS-CoV-2 infection and protein expression but did not support productive virus replication. Importantly, SARS-CoV-2 launched an attenuated interferon response in both cell types and triggered significant proinflammatory cytokine/chemokine expression in MDMs but not moDCs. Investigations suggested that this attenuated immune response to SARS-CoV-2 in moDCs was associated with viral antagonism of STAT1 phosphorylation. These findings may explain the mild and insidious course of COVID-19 until late deterioration.


Asunto(s)
Betacoronavirus/fisiología , Infecciones por Coronavirus/inmunología , Células Dendríticas/inmunología , Interferones/inmunología , Monocitos/inmunología , Neumonía Viral/inmunología , Factor de Transcripción STAT1/antagonistas & inhibidores , Inmunidad Adaptativa , Animales , Betacoronavirus/inmunología , Betacoronavirus/aislamiento & purificación , Betacoronavirus/metabolismo , COVID-19 , Quimiocinas/metabolismo , Chlorocebus aethiops , Infecciones por Coronavirus/metabolismo , Infecciones por Coronavirus/virología , Citocinas/metabolismo , Células Dendríticas/metabolismo , Células Dendríticas/virología , Humanos , Macrófagos/inmunología , Macrófagos/virología , Monocitos/virología , Pandemias , Fosforilación , Neumonía Viral/metabolismo , Neumonía Viral/virología , SARS-CoV-2 , Factor de Transcripción STAT1/inmunología , Factor de Transcripción STAT1/metabolismo , Células Vero , Replicación Viral/fisiología , Esparcimiento de Virus
15.
Clin Infect Dis ; 71(6): 1400-1409, 2020 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-32270184

RESUMEN

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an emerging coronavirus that has resulted in more than 2 000 000 laboratory-confirmed cases including over 145 000 deaths. Although SARS-CoV-2 and SARS-CoV share a number of common clinical manifestations, SARS-CoV-2 appears to be highly efficient in person-to-person transmission and frequently causes asymptomatic or presymptomatic infections. However, the underlying mechanisms that confer these viral characteristics of high transmissibility and asymptomatic infection remain incompletely understood. METHODS: We comprehensively investigated the replication, cell tropism, and immune activation profile of SARS-CoV-2 infection in human lung tissues with SARS-CoV included as a comparison. RESULTS: SARS-CoV-2 infected and replicated in human lung tissues more efficiently than SARS-CoV. Within the 48-hour interval, SARS-CoV-2 generated 3.20-fold more infectious virus particles than did SARS-CoV from the infected lung tissues (P < .024). SARS-CoV-2 and SARS-CoV were similar in cell tropism, with both targeting types I and II pneumocytes and alveolar macrophages. Importantly, despite the more efficient virus replication, SARS-CoV-2 did not significantly induce types I, II, or III interferons in the infected human lung tissues. In addition, while SARS-CoV infection upregulated the expression of 11 out of 13 (84.62%) representative proinflammatory cytokines/chemokines, SARS-CoV-2 infection only upregulated 5 of these 13 (38.46%) key inflammatory mediators despite replicating more efficiently. CONCLUSIONS: Our study provides the first quantitative data on the comparative replication capacity and immune activation profile of SARS-CoV-2 and SARS-CoV infection in human lung tissues. Our results provide important insights into the pathogenesis, high transmissibility, and asymptomatic infection of SARS-CoV-2.


Asunto(s)
Betacoronavirus/fisiología , Infecciones por Coronavirus/inmunología , Inmunidad Innata/inmunología , Neumonía Viral/inmunología , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/fisiología , Replicación Viral/inmunología , COVID-19 , Quimiocinas/inmunología , Infecciones por Coronavirus/virología , Citocinas/inmunología , Humanos , Interferones/inmunología , Pulmón/inmunología , Pulmón/virología , Pandemias , Neumonía Viral/virología , SARS-CoV-2
16.
Ann Hematol ; 99(6): 1303-1309, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32333152

RESUMEN

Coagulative dysfunction is frequently observed among patients with extranodal nasal-type natural killer/T cell lymphoma (NKTCL) in our clinical practice. However, the true prognostic value of coagulation factors in patients with NKTCL has not been evaluated systemically. Data for patients with stage I/II NKTCL who were treated in the Cancer Hospital, Chinese Academy of Medical Sciences, from January 2008 to January 2019 were collected retrospectively. The patients enrolled in this study were initially diagnosed as having early-stage disease. The patients' baseline characteristics and pretreatment laboratory tests for coagulation function, including fibrinogen (FIB) and D-dimer (D-D), were reviewed and analyzed. The influence of coagulative factors on the responses and prognosis of patients with early-stage NKTCL was evaluated. Among 394 patients assessed, 154 were included in this study. Abnormal coagulation function was found in nearly half of the patients (48.1%). Univariate analysis showed that reduced complete remission (CR) was associated with elevated D-D (P = 0.001) and elevated FIB levels (P = 0.006). The D-D level was demonstrated as associated with unfavorable progression-free survival (PFS) (P = 0.003) and overall survival (OS) (P = 0.002). Multivariate analysis indicated that an elevated D-D level was an independent factor for poor clinical response (P = 0.019), PFS (P = 0.046), and OS (P = 0.024). Elevated pretreatment levels of coagulation factors, especially D-D and plasma FIB, are unfavorable predictors for clinical response, OS, and PFS in early-stage NKTCL.


Asunto(s)
Factores de Coagulación Sanguínea/metabolismo , Detección Precoz del Cáncer/métodos , Linfoma Extranodal de Células NK-T/sangre , Linfoma Extranodal de Células NK-T/diagnóstico por imagen , Adolescente , Adulto , Anciano , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias/métodos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Pronóstico , Estudios Retrospectivos , Adulto Joven
17.
J Virol ; 92(24)2018 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-30282705

RESUMEN

Porcine reproductive and respiratory syndrome virus (PRRSV) is a positive-stranded RNA virus belonging to the family Arteriviridae Synthesis of the viral RNA is directed by replication/transcription complexes (RTC) that are mainly composed of a network of PRRSV nonstructural proteins (nsps) and likely cellular proteins. Here, we mapped the interaction network among PRRSV nsps by using yeast two-hybrid screening in conjunction with coimmunoprecipitation (co-IP) and cotransfection assays. We identified a total of 24 novel interactions and found that the interactions were centered on open reading frame 1b (ORF1b)-encoded nsps that were mainly connected by the transmembrane proteins nsp2, nsp3, and nsp5. Interestingly, the interactions of the core enzymes nsp9 and nsp10 with transmembrane proteins did not occur in a straightforward manner, as they worked in the co-IP assay but were poorly capable of finding each other within intact mammalian cells. Further proof that they can interact within cells required the engineering of N-terminal truncations of both nsp9 and nsp10. However, despite the poor colocalization relationship in cotransfected cells, both nsp9 and nsp10 came together with membrane proteins (e.g., nsp2) at the viral replication and transcription complexes (RTC) in PRRSV-infected cells. Thus, our results indicate the existence of a complex interaction network among PRRSV nsps and raise the possibility that the recruitment of key replicase proteins to membrane-associated nsps may involve some regulatory mechanisms during infection.IMPORTANCE Synthesis of PRRSV RNAs within host cells depends on the efficient and correct assembly of RTC that takes places on modified intracellular membranes. As an important step toward dissecting this poorly understood event, we investigated the interaction network among PRRSV nsps. Our studies established a comprehensive interaction map for PRRSV nsps and revealed important players within the network. The results also highlight the likely existence of a regulated recruitment of the PRRSV core enzymes nsp9 and nsp10 to viral membrane nsps during PRRSV RTC assembly.


Asunto(s)
Virus del Síndrome Respiratorio y Reproductivo Porcino/fisiología , Mapas de Interacción de Proteínas , Proteínas no Estructurales Virales/metabolismo , Animales , Redes Reguladoras de Genes , Inmunoprecipitación , Virus del Síndrome Respiratorio y Reproductivo Porcino/metabolismo , Porcinos , Técnicas del Sistema de Dos Híbridos , Proteínas no Estructurales Virales/química , Replicación Viral
18.
Signal Transduct Target Ther ; 9(1): 192, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39090094

RESUMEN

Metastasis remains a pivotal characteristic of cancer and is the primary contributor to cancer-associated mortality. Despite its significance, the mechanisms governing metastasis are not fully elucidated. Contemporary findings in the domain of cancer biology have shed light on the molecular aspects of this intricate process. Tumor cells undergoing invasion engage with other cellular entities and proteins en route to their destination. Insights into these engagements have enhanced our comprehension of the principles directing the movement and adaptability of metastatic cells. The tumor microenvironment plays a pivotal role in facilitating the invasion and proliferation of cancer cells by enabling tumor cells to navigate through stromal barriers. Such attributes are influenced by genetic and epigenetic changes occurring in the tumor cells and their surrounding milieu. A profound understanding of the metastatic process's biological mechanisms is indispensable for devising efficacious therapeutic strategies. This review delves into recent developments concerning metastasis-associated genes, important signaling pathways, tumor microenvironment, metabolic processes, peripheral immunity, and mechanical forces and cancer metastasis. In addition, we combine recent advances with a particular emphasis on the prospect of developing effective interventions including the most popular cancer immunotherapies and nanotechnology to combat metastasis. We have also identified the limitations of current research on tumor metastasis, encompassing drug resistance, restricted animal models, inadequate biomarkers and early detection methods, as well as heterogeneity among others. It is anticipated that this comprehensive review will significantly contribute to the advancement of cancer metastasis research.


Asunto(s)
Metástasis de la Neoplasia , Neoplasias , Microambiente Tumoral , Humanos , Microambiente Tumoral/genética , Microambiente Tumoral/efectos de los fármacos , Neoplasias/genética , Neoplasias/patología , Neoplasias/terapia , Animales , Inmunoterapia , Transducción de Señal
19.
Small Methods ; 8(8): e2301319, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38178653

RESUMEN

The nitrogen doping (N-doping) treatment for niobium superconducting radio-frequency (SRF) cavities is one of the key enabling technologies that support the development of more efficient future large accelerators. However, the N-doping results have diverged due to a complex chemical profile under the nitrogen-doped surface. Particularly, under industrial-scale production conditions, it is difficult to understand the underlying mechanism thus hindering performance improvement. Herein, a combination of spatially resolved and surface-sensitive approaches is employed to establish the detailed near-surface phase composition of thermally processed niobium. The results show that intermediate phase segregations, particularly the nanometric carbon-rich phase, can impede the nitridation process and limit the interactions between nitrogen and the niobium sub-surface. In comparison, the removal of the carbon-rich layer at the Nb surface leads to enhanced nitrogen binding at the Nb surface. Combining the RF test results, it is shown that the complex uniformity and grain boundary penetrations of impurity elements have a direct correlation with the mid-field quench behavior in the N-doped Nb cavities. Therefore, proper control of the nanometric intermediate phase formation in discrete thermal steps is critical in improving the ultimate performance and production yield of the Nb cavities.

20.
EBioMedicine ; 99: 104916, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38101297

RESUMEN

BACKGROUND: Earlier Omicron subvariants including BA.1, BA.2, and BA.5 emerged in waves, with a subvariant replacing the previous one every few months. More recently, the post-BA.2/5 subvariants have acquired convergent substitutions in spike that facilitated their escape from humoral immunity and gained ACE2 binding capacity. However, the intrinsic pathogenicity and replication fitness of the evaluated post-BA.2/5 subvariants are not fully understood. METHODS: We systemically investigated the replication fitness and intrinsic pathogenicity of representative post-BA.2/5 subvariants (BL.1, BQ.1, BQ.1.1, XBB.1, CH.1.1, and XBB.1.5) in weanling (3-4 weeks), adult (8-10 weeks), and aged (10-12 months) mice. In addition, to better model Omicron replication in the human nasal epithelium, we further investigated the replication capacity of the post-BA.2/5 subvariants in human primary nasal epithelial cells. FINDINGS: We found that the evaluated post-BA.2/5 subvariants are consistently attenuated in mouse lungs but not in nasal turbinates when compared with their ancestral subvariants BA.2/5. Further investigations in primary human nasal epithelial cells revealed a gained replication fitness of XBB.1 and XBB.1.5 when compared to BA.2 and BA.5.2. INTERPRETATION: Our study revealed that the post-BA.2/5 subvariants are attenuated in lungs while increased in replication fitness in the nasal epithelium, indicating rapid adaptation of the circulating Omicron subvariants in the human populations. FUNDING: The full list of funding can be found at the Acknowledgements section.


Asunto(s)
COVID-19 , SARS-CoV-2 , Adulto , Humanos , Animales , Ratones , Virulencia , Células Epiteliales , Mucosa Nasal
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