Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 79
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
J Infect Chemother ; 29(9): 869-874, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37178973

RESUMEN

BACKGROUND: Convalescent plasma is a potential therapeutic option for patients with coronavirus disease 2019 (COVID-19). Despite its use for treating several viral infections, we lack comprehensive data on its efficacy against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). METHODS: We conducted a multicenter, open-label, randomized controlled trial of convalescent plasma therapy with high neutralizing activity against SARS-CoV-2 in high-risk patients within five days after the onset of COVID-19 symptoms. The primary endpoint was the time-weighted average change in the SARS-CoV-2 viral load in nasopharyngeal swabs from days 0-5. RESULTS: Between February 24, 2021, and November 30, 2021, 25 patients were randomly assigned to either convalescent plasma (n = 14) or standard of care (n = 11) groups. Four patients discontinued their allocated convalescent plasma, and 21 were included in the modified intention-to-treat analysis. The median interval between the symptom onset and plasma administration was 4.5 days (interquartile range, 3-5 days). The primary outcome of the time-weighted average change in the SARS-CoV-2 viral load in nasopharyngeal swabs did not significantly differ between days 0-5 (1.2 log10 copies/mL in the convalescent plasma vs. 1.2 log10 copies/mL in the standard of care (effect estimate, 0.0 [95% confidence interval, -0.8-0.7]; P = 0.94)). No deaths were observed in either group. CONCLUSIONS: The early administration of convalescent plasma with high neutralizing activity did not contribute to a decrease in the viral load within five days compared with the standard of care alone.


Asunto(s)
COVID-19 , Humanos , COVID-19/terapia , SARS-CoV-2 , Japón , Sueroterapia para COVID-19 , Inmunización Pasiva/efectos adversos , Resultado del Tratamiento
2.
Emerg Infect Dis ; 28(4): 870-872, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35148495

RESUMEN

A 32-year-old man in Japan experienced respiratory failure after receiving the first dose of coronavirus disease (COVID-19) vaccine. He was treated with noninvasive ventilation and corticosteroids. Serologic test results suggested previous COVID-19; therefore, he received a diagnosis of multisystem inflammatory syndrome. COVID-19 vaccination could be a trigger for this condition.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Adulto , COVID-19/prevención & control , Vacunas contra la COVID-19/efectos adversos , Humanos , Masculino , SARS-CoV-2 , Vacunas Sintéticas , Vacunas de ARNm
3.
Exp Cell Res ; 409(1): 112893, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34695436

RESUMEN

Nuclear trafficking peptide (NTP), a cell-penetrating peptide (CPP) composed of 10 amino acids (aa) (RIFIHFRIGC), has potent nuclear trafficking activity. Recently, we established a protein-based cell engineering system by using NTP, but it remained elusive how NTP functions as a CPP with nuclear orientation. In the present study, we identified importin subunit ß1 (IMB1) and transportin 1 (TNPO1) as cellular proteins underlying the activity of NTP. These karyopherin nuclear transport receptors were identified as candidate molecules by liquid chromatography/mass spectrometry analysis, and downregulation of each protein by small interfering RNA significantly reduced NTP activity (P < 0.01). Biochemical analyses revealed that NTP bound directly to both molecules, and the forced expression of an IMB1 fragment (296-516 aa) or TNPO1 fragment (1-297 aa), which both contain binding sites to NTP, reduced nuclear NTP-green fluorescent protein (GFP) levels when it was added to cell culture medium. NTP is derived from viral protein R (Vpr) of human immunodeficiency virus-1, and Vpr enters the nucleus and exerts pleiotropic functions. Notably, Vpr bound directly to IMB1 and TNPO1, and its function was significantly impaired by the forced expression of the 296-516-aa fragment of IMB1 and 1-297-aa fragment of TNPO1. Interestingly, NTP completely blocked the physical association of Vpr with IMB1 and TNPO1. Although the nuclear localization mechanism of Vpr remains unknown, our data suggest that NTP functions as a novel nuclear localization signal of Vpr.


Asunto(s)
Núcleo Celular/metabolismo , Carioferinas/metabolismo , Señales de Localización Nuclear/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Transporte Activo de Núcleo Celular/fisiología , Línea Celular Tumoral , Citoplasma/metabolismo , Proteínas Fluorescentes Verdes/metabolismo , Células HeLa , Humanos , beta Carioferinas/metabolismo , Productos del Gen vpr del Virus de la Inmunodeficiencia Humana/metabolismo
4.
J Infect Chemother ; 28(7): 962-964, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35461768

RESUMEN

There have been several reports of breakthrough infections, which are defined as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections among individuals who had received at least two doses of vaccine at least 14 days before the onset of infection, but data on the antibody titers, including SARS-CoV-2 neutralizing antibody activity, and the clinical course of individuals with breakthrough infections are limited. We encountered a case of breakthrough infection with the SARS-CoV-2 delta variant in a 31-year-old female healthcare worker (the index case, Case 1) and a secondary case (Case 2) in her unvaccinated 33-year-old husband. We studied the role of the anti-spike immunoglobulin G (IgG) and neutralizing antibody activity in the two case patients. Case 1 had high anti-spike IgG detected on day 3 of the illness, with low neutralizing antibody activity. The neutralizing antibody activity started to increase on day 5 of the illness. In Case 2 both the anti-spike IgG and the neutralizing antibody activity remained low from days 4-11 of illness, and the anti-spike IgG gradually increased from day 9. In Case 1, the fever broke within 4 days of onset, coinciding with the rise in neutralizing antibodies, whereas the fever took 7 days to resolve in Case 2. SARS-CoV-2 infection can occur even in vaccinated individuals, but vaccination may contribute to milder clinical symptoms because neutralizing antibodies are induced earlier in vaccinated individuals than in unvaccinated individuals.


Asunto(s)
COVID-19 , SARS-CoV-2 , Adulto , Anticuerpos Neutralizantes , Anticuerpos Antivirales , COVID-19/prevención & control , Vacunas contra la COVID-19 , Femenino , Humanos , Inmunoglobulina G , Vacunación
5.
J Infect Chemother ; 28(7): 971-974, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35184976

RESUMEN

Corticosteroids are widely used to treat severe COVID-19, but in immunocompromised individuals, who are susceptible to persistent infection, long term corticosteroid use may delay viral clearance. We present a case of prolonged SARS-CoV-2 infection in a man with significantly impaired B-cell immunity due to non-Hodgkin lymphoma which had been treated with rituximab. SARS-CoV-2 shedding persisted, despite treatment with remdesivir. Viral sequencing confirmed the persistence of the same viral strain, ruling out the possibility of reinfection. Although SARS-CoV-2 IgG, IgA and IgM remained negative throughout the treatment period, after reduction of the corticosteroid dose, PCR became negative. Long-term corticosteroid treatment, especially in immunocompromised individuals, may result in suppression of cell-mediated immunity and prolonged SARS-CoV-2 infection.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , Anticuerpos Antivirales , Humanos , Huésped Inmunocomprometido , Masculino , Rituximab/efectos adversos , SARS-CoV-2
6.
Transfusion ; 61(7): 1998-2007, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34096059

RESUMEN

BACKGROUND: In order to tackle the COVID-19 pandemic, a COVID-19 convalescent plasma (CCP) procurement program was initiated in Japan in April 2020. The program was a collaboration between a government-managed national hospital, an infectious disease research institute, and a blood banking organization. Each party assumed different responsibilities: recruitment, SARS-CoV-2 antibody profiling, and plasmapheresis; conduction of screening tests; and SARS-CoV-2 blood testing, respectively. METHODS: We adopted a two-point screening approach before the collected CCP was labeled as a CCP product for investigational use, for which we mainly tested anti-SARS-CoV-2 antibody eligibility and blood product eligibility. Anti-SARS-CoV-2 spike protein titer was measured using enzyme-linked immunosorbent assay, and the IC50 value was denoted as the neutralizing activity. Blood donor eligibility was extended beyond the normal blood donation guidelines to include a broader range of participants. After both eligibility criteria were confirmed, participants were asked to revisit the hospital for blood donation, which is a unique aspect of the Japanese CCP program, as most donations are taking place in normal blood donation venues in other countries. Some donors were re-scheduled for repeat plasma donations. As public interest in anti-SARS-CoV-2 antibodies increased, test results were given to the participants. RESULTS: As of September 17, 2020, our collection of CCP products was sufficient to treat more than 100 patients. As a result, projects for administration and distribution are also being conducted. CONCLUSIONS: We successfully implemented a CCP procurement scheme with the goal to expand to other parts of the country to improve treatment options for COVID-19.


Asunto(s)
Donantes de Sangre , COVID-19/inmunología , COVID-19/virología , Convalecencia , Sueros Inmunes/inmunología , SARS-CoV-2/inmunología , Adulto , Anciano , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Conservación de la Sangre , COVID-19/diagnóstico , COVID-19/epidemiología , Femenino , Humanos , Inmunización Pasiva/métodos , Japón , Masculino , Tamizaje Masivo , Persona de Mediana Edad , Pandemias , Plasmaféresis , Adulto Joven
7.
J Infect Chemother ; 27(6): 808-813, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33531292

RESUMEN

INTRODUCTION: Among patients with coronavirus disease 2019 (COVID-19), the factors that affect anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody production remain unclear. This study aimed to identify such factors among patients convalescing from COVID-19. METHODS: This study comprised patients who had been diagnosed with COVID-19 between January 1 and June 30, 2020 and gave consent for anti-SARS-CoV-2 spike protein antibody measurement using enzyme-linked immunosorbent assay during their acute and/or convalescent phases. Factors related to elevated antibody titers and the relationship between the days from disease onset and the development of antibody titers were assessed. RESULTS: A total of 84 participants enrolled in the study. Nineteen participants had antibody titers measured during the convalescent phase only, and 65 participants had antibody titers measured during the acute and convalescent phases. The antibody titers peaked in weeks 5 and 6. The stepwise multivariate log-normal analysis revealed that male sex (P = 0.04), diabetes mellitus (P = 0.03), and high C-reactive protein levels during the disease course (P < 0.001) were associated with elevated IgG antibodies. Glucocorticoid use was not associated with antibody titers. CONCLUSION: The study found that high values of maximum CRP levels during the acute phase, male sex, and diabetes mellitus were associated with elevated antibody titers. Antibody titers tended to be highest in the first 5 or 6 weeks after the onset of symptoms.


Asunto(s)
Anticuerpos Antivirales/inmunología , Formación de Anticuerpos , COVID-19/inmunología , Adulto , Anciano , Antagonistas de Receptores de Angiotensina , Inhibidores de la Enzima Convertidora de Angiotensina , Femenino , Humanos , Inmunoglobulina G/inmunología , Masculino , Persona de Mediana Edad , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus/inmunología
8.
J Infect Chemother ; 27(7): 1063-1067, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33962861

RESUMEN

INTRODUCTION: "Re-infection" with COVID-19 is a growing concern; re-infection cases have reported worldwide. However, the clinical characteristics of SARS-CoV-2 re-infection, including the levels and role of anti-SARS-CoV-2 Spike protein IgG antibodies and the half-maximal concentration (IC50) of neutralizing antibodies remain unknown. METHODS: Both the epidemiological and clinical information has been collected during two episodes of COVID-19 in a patient. Laboratory results, including RT-PCR, Ct values, anti-SARS-CoV-2 Spike protein IgG antibodies, and the IC50 of neutralizing antibodies levels were analyzed on the patient. RESULTS: The patient was a 58-year-old man who developed moderate COVID-19 pneumonia with oxygen demand (cannula 2 L/min) in the first episode. By day 30, he recuperated and was discharged after testing negative for SARS-CoV-2. After two and a half months, his three family members showed COVID-19 symptoms and tested positive for SARS-CoV-2. He tested positive for SARS-CoV-2 once again and was asymptomatic (the second episode). The IC50 of neutralizing antibodies against SARS-CoV-2 greatly increased from 50.0 µg/mL (after the first episode) to 14.8 µg/mL (after the second episode), and remained strongly reactive (20.1 µl/mL) after 47 days of the second episode. CONCLUSIONS: Epidemiological, clinical, and serological analyses confirmed that the patient had re-infection instead of persistent viral shedding from first infection. Our results suggest that SARS-CoV-2 re-infection may manifest as asymptomatic with increased neutralizing antibody levels. Further studies such as the virus characteristics, immunology, and epidemiology on SARS-CoV-2 re-infection are needed.


Asunto(s)
Anticuerpos Neutralizantes , COVID-19 , Anticuerpos Antivirales , Humanos , Japón , Masculino , Persona de Mediana Edad , Reinfección , SARS-CoV-2
9.
Br J Cancer ; 122(6): 823-834, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31959920

RESUMEN

BACKGROUND: Immune checkpoint blockade (ICB) therapy improved the prognosis of cancer patients, but general administration of ICBs occasionally induces side effects that include immune-related adverse events and tumour hyper-progression. Here, we established a protein-based system, by which endogenous expression of IC molecule in natural killer (NK) cells was transiently repressed on enhancement of their antitumour activity. METHODS: A protein-based genome modulator (GM) system is composed of a transcription activator-like effector (TALE), DNA methyltransferase and a newly identified potent cell-penetrating peptide with nuclear-trafficking property named NTP. TALE was designed to target the promoter region of the programmed cell death-1 (PD-1) gene. After culturing human NK cells in the presence of NTP-GM protein, we examined endogenous PD-1 expression and antitumour activity of the treated cells. RESULTS: NTP-GM protein efficiently downregulated PD-1 expression in NK cells with increased CpG DNA methylation in the promoter region. The antitumour activity of the treated NK cells was enhanced, and repeated intraperitoneal administrations of the treated NK cells attenuated tumour growth of programmed death-ligand 1-positive tumour cells in vivo. CONCLUSIONS: Because the incorporated NTP-GM protein was quickly degraded and negligible in the administered NK cells, the NTP-GM system could be an alternative option of an ICB without side effects.


Asunto(s)
Represión Epigenética/inmunología , Proteínas de Punto de Control Inmunitario/inmunología , Células Asesinas Naturales/inmunología , Neoplasias/inmunología , Receptor de Muerte Celular Programada 1/inmunología , Animales , Humanos , Ratones , Pronóstico
10.
Exp Mol Pathol ; 114: 104433, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32243892

RESUMEN

Combination antiretroviral therapy (cART) has greatly improved the prognosis of patients with human immunodeficiency virus type-1 (HIV-1) infection. However, cardiovascular disease (CVD) remains a serious issue even in the post-cART era. Viral protein R (Vpr), an accessory gene product of HIV-1, exerts pleiotropic activities such as the induction of DNA damage signals, apoptosis by mitochondrial membrane depolarization, G2/M-phase cell cycle abnormalities, and retrotransposition. Importantly, some of these cellular responses are induced by the trans-acting activity of Vpr. Recently, we established an enzyme-linked immunosorbent assay to detect Vpr and reported that about 22% of blood samples from 100 HIV-1-positive patients were positive for Vpr. Here, we investigated the biological effects of recombinant Vpr (rVpr) in vivo. We observed that repeated injections of rVpr increased the copy number of long interspersed element-1 (L1) in the heart genome in mice. rVpr also increased the number of cells positive for senescence-associated ß-galactosidase (SA-ß-gal) and fibrosis in the heart. Notably, co-administration of a reverse transcriptase inhibitor reduced the number of rVpr-induced SA-ß-gal-positive cells and fibrosis concomitantly with the attenuation of L1 retrotransposition. Interestingly, a Vpr mutant defective for mitochondrial dysfunction also induced heart senescence and increased L1 copy number. Together with a recent report that L1 retrotransposition functions as a molecular basis of senescence, our current data suggest that rVpr-induced L1 retrotransposition is linked with senescence in heart tissue. We would propose that Vpr in the bloodstream may be one of risk factors for CVD, and that its monitoring will lead to well understanding of the heterogeneity and multifactorial mechanisms of CVD in HIV-1 patients.


Asunto(s)
Senescencia Celular/genética , Infecciones por VIH/genética , Retroelementos/genética , Productos del Gen vpr del Virus de la Inmunodeficiencia Humana/genética , Animales , Infecciones por VIH/virología , VIH-1/patogenicidad , Corazón/fisiopatología , Corazón/virología , Humanos , Ratones
11.
Retrovirology ; 15(1): 8, 2018 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-29338752

RESUMEN

BACKGROUND: Viral protein R (Vpr) is an accessory protein of HIV-1, which is potentially involved in the infection of macrophages and the induction of the ataxia-telangiectasia and Rad3-related protein (ATR)-mediated DNA damage response (DDR). It was recently proposed that the SLX4 complex of structure-specific endonuclease is involved in Vpr-induced DDR, which implies that aberrant DNA structures are responsible for this phenomenon. However, the mechanism by which Vpr alters the DNA structures remains unclear. RESULTS: We found that Vpr unwinds double-stranded DNA (dsDNA) and invokes the loading of RPA70, which is a single-stranded DNA-binding subunit of RPA that activates the ATR-dependent DDR. We demonstrated that Vpr influenced RPA70 to accumulate in the corresponding region utilizing the LacO/LacR system, in which Vpr can be tethered to the LacO locus. Interestingly, RPA70 recruitment required chromatin remodelling via Vpr-mediated ubiquitination of histone H2B. On the contrary, Q65R mutant of Vpr, which lacks ubiquitination activity, was deficient in both chromatin remodelling and RPA70 loading on to the chromatin. Moreover, Vpr-induced unwinding of dsDNA coincidently resulted in the accumulation of negatively supercoiled DNA and covalent complexes of topoisomerase 1 and DNA, which caused DNA double-strand breaks (DSBs) and DSB-directed integration of proviral DNA. Lastly, we noted the dependence of Vpr-promoted HIV-1 infection in resting macrophages on topoisomerase 1. CONCLUSIONS: The findings of this study indicate that Vpr-induced structural alteration of DNA is a primary event that triggers both DDR and DSB, which ultimately contributes to HIV-1 infection.


Asunto(s)
Daño del ADN/fisiología , ADN-Topoisomerasas de Tipo I/metabolismo , ADN Superhelicoidal/metabolismo , VIH-1/química , Productos del Gen vpr del Virus de la Inmunodeficiencia Humana/fisiología , Línea Celular , Cromatina/metabolismo , Roturas del ADN de Doble Cadena , ADN-Topoisomerasas de Tipo I/genética , Regulación hacia Abajo , Histonas/metabolismo , Humanos , Macrófagos/virología , Modelos Biológicos , Proteína de Replicación A/metabolismo , Sumoilación , Ubiquitinación , Integración Viral
12.
FASEB J ; 30(12): 4149-4158, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27601443

RESUMEN

Fatty acids are taken up by cells and incorporated into complex lipids such as neutral lipids and glycerophospholipids. Glycerophospholipids are major constituents of cellular membranes. More than 1000 molecular species of glycerophospholipids differ in their polar head groups and fatty acid compositions. They are related to cellular functions and diseases and have been well analyzed by mass spectrometry. However, intracellular imaging of fatty acids and glycerophospholipids has not been successful due to insufficient resolution using conventional methods. Here, we developed a method for labeling fatty acids with bromine (Br) and applied scanning X-ray fluorescence microscopy (SXFM) to obtain intracellular Br mapping data with submicrometer resolution. Mass spectrometry showed that cells took up Br-labeled fatty acids and metabolized them mainly into glycerophospholipids in CHO cells. Most Br signals observed by SXFM were in the perinuclear region. Higher resolution revealed a spot-like distribution of Br in the cytoplasm. The current method enabled successful visualization of intracellular Br-labeled fatty acids. Single-element labeling combined with SXFM technology facilitates the intracellular imaging of fatty acids, which provides a new tool to determine dynamic changes in fatty acids and their derivatives at the single-cell level.-Shimura, M., Shindou, H., Szyrwiel, L., Tokuoka, S. M., Hamano, F., Matsuyama, S., Okamoto, M., Matsunaga, A., Kita, Y., Ishizaka, Y., Yamauchi, K., Kohmura, Y., Lobinski, R., Shimizu, I., Shimizu, T. Imaging of intracellular fatty acids by scanning X-ray fluorescence microscopy.


Asunto(s)
Membrana Celular/metabolismo , Ácidos Grasos/metabolismo , Glicerofosfolípidos/metabolismo , Animales , Células CHO , Cricetinae , Cricetulus , Citoplasma/metabolismo , Metabolismo de los Lípidos , Lípidos , Microscopía Fluorescente/métodos , Rayos X
13.
J Biol Chem ; 289(37): 25476-85, 2014 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-25053411

RESUMEN

Long interspersed element 1 (L1) is a retroelement constituting ∼17% of the human genome. A single human cell has 80-100 copies of L1 capable of retrotransposition (L1-RTP), ∼10% of which are "hot L1" copies, meaning they are primed for "jumping" within the genome. Recent studies demonstrated induction of L1 activity by drugs of abuse or low molecular weight compounds, but little is known about the underlying mechanism. The aim of this study was to identify the mechanism and effects of methamphetamine (METH) and cocaine on L1-RTP. Our results revealed that METH and cocaine induced L1-RTP in neuronal cell lines. This effect was found to be reverse transcriptase-dependent. However, METH and cocaine did not induce double-strand breaks. RNA interference experiments combined with add-back of siRNA-resistant cDNAs revealed that the induction of L1-RTP by METH or cocaine depends on the activation of cAMP response element-binding protein (CREB). METH or cocaine recruited the L1-encoded open reading frame 1 (ORF1) to chromatin in a CREB-dependent manner. These data suggest that the cellular cascades underlying METH- and cocaine-induced L1-RTP are different from those behind L1-RTP triggered by DNA damage; CREB is involved in drug-induced L1-RTP. L1-RTP caused by drugs of abuse is a novel type of genomic instability, and analysis of this phenomenon might be a novel approach to studying substance-use disorders.


Asunto(s)
Cocaína/administración & dosificación , Inestabilidad Genómica/efectos de los fármacos , Elementos de Nucleótido Esparcido Largo/efectos de los fármacos , Metanfetamina/administración & dosificación , Proteína de Unión a CREB/metabolismo , Línea Celular , Cromatina/efectos de los fármacos , Daño del ADN/efectos de los fármacos , Daño del ADN/genética , Inestabilidad Genómica/genética , Humanos , Neuronas/efectos de los fármacos , Interferencia de ARN , ADN Polimerasa Dirigida por ARN/metabolismo
14.
PLoS Pathog ; 9(12): e1003812, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24339781

RESUMEN

The precise role of viral protein R (Vpr), an HIV-1-encoded protein, during HIV-1 infection and its contribution to the development of AIDS remain unclear. Previous reports have shown that Vpr has the ability to cause G2 cell cycle arrest and apoptosis in HIV-1-infected cells in vitro. In addition, vpr is highly conserved in transmitted/founder HIV-1s and in all primate lentiviruses, which are evolutionarily related to HIV-1. Although these findings suggest an important role of Vpr in HIV-1 pathogenesis, its direct evidence in vivo has not been shown. Here, by using a human hematopoietic stem cell-transplanted humanized mouse model, we demonstrated that Vpr causes G2 cell cycle arrest and apoptosis predominantly in proliferating CCR5(+) CD4(+) T cells, which mainly consist of regulatory CD4(+) T cells (Tregs), resulting in Treg depletion and enhanced virus production during acute infection. The Vpr-dependent enhancement of virus replication and Treg depletion is observed in CCR5-tropic but not CXCR4-tropic HIV-1-infected mice, suggesting that these effects are dependent on the coreceptor usage by HIV-1. Immune activation was observed in CCR5-tropic wild-type but not in vpr-deficient HIV-1-infected humanized mice. When humanized mice were treated with denileukin diftitox (DD), to deplete Tregs, DD-treated humanized mice showed massive activation/proliferation of memory T cells compared to the untreated group. This activation/proliferation enhanced CCR5 expression in memory CD4(+) T cells and rendered them more susceptible to CCR5-tropic wild-type HIV-1 infection than to vpr-deficient virus. Taken together, these results suggest that Vpr takes advantage of proliferating CCR5(+) CD4(+) T cells for enhancing viremia of CCR5-tropic HIV-1. Because Tregs exist in a higher cycling state than other T cell subsets, Tregs appear to be more vulnerable to exploitation by Vpr during acute HIV-1 infection.


Asunto(s)
Linfocitos T CD4-Positivos/virología , Infecciones por VIH/inmunología , Infecciones por VIH/virología , VIH-1/fisiología , Replicación Viral , Productos del Gen vpr del Virus de la Inmunodeficiencia Humana/fisiología , Enfermedad Aguda , Animales , Animales Recién Nacidos , Linfocitos T CD4-Positivos/inmunología , Proliferación Celular , Células Cultivadas , Humanos , Ratones , Ratones Endogámicos NOD , Ratones SCID , Ratones Transgénicos , Viremia/inmunología
15.
Microbiol Immunol ; 59(7): 398-409, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25990091

RESUMEN

Viral protein R (Vpr) of HIV-1 plays an important role in viral replication in macrophages. Various lines of evidence suggest that expression of Vpr in macrophages causes immunopathogenesis; however, the underlying mechanism is not yet fully understood. In this study, it was shown that recombinant Vpr (rVpr) induces retrotransposition of long interspersed element-1 in RAW264.7, a macrophage-like cell line, and activates reverse transcriptase-dependent immunotoxic cascades including production of IFN-ß and phosphorylation of signal transducer and activator of transcription 1 (STAT1). Knockout experiments based on the CRISPR/Cas9 nickase system further demonstrated that cyclic guanosine monophosphate-adenosine monophosphate synthase (cGAS) and stimulator of interferon gene (STING) are responsible for IFN-ß production and STAT1 phosphorylation, respectively. Moreover, rVpr was found to increase production of glutaminase C, a regulator of glutamate synthesis, which is also dependent on the cGAS-STING pathway. Taken together with reports that glutaminase C is involved in the pathogenesis of HIV-associated neurocognitive disorder (HAND) and that Vpr is detectable in the cerebrospinal fluid of HIV-1-positive patients, a possible role of Vpr-induced L1-RTP and immunotoxic cascades in the development of HAND is discussed.


Asunto(s)
Glutamatos/biosíntesis , Infecciones por VIH/metabolismo , VIH-1/genética , VIH-1/metabolismo , Factor de Transcripción STAT1/metabolismo , Productos del Gen vpr del Virus de la Inmunodeficiencia Humana/metabolismo , Animales , Infecciones por VIH/genética , Infecciones por VIH/virología , Humanos , Elementos de Nucleótido Esparcido Largo , Macrófagos/metabolismo , Macrófagos/virología , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones , Nucleotidiltransferasas/genética , Nucleotidiltransferasas/metabolismo , Fosforilación , Células RAW 264.7 , Factor de Transcripción STAT1/genética , Transducción de Señal , Productos del Gen vpr del Virus de la Inmunodeficiencia Humana/genética
16.
Exp Lung Res ; 41(1): 21-31, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25275723

RESUMEN

INTRODUCTION: Pulmonary hypertension (PH) is characterized by increased pressure in the pulmonary artery and right ventricular hypertrophy (RVH). Recently, angiotensin-converting enzyme 2 (ACE2), which converts angiotensin (Ang) II into Ang-(1-7), was shown to inhibit experimental PH. Here we identified a novel ACE2 activator and investigated how the compound reduced monocrotaline (MCT)-induced PH. METHODS: To induce PH, Sprague-Dawley rats were injected subcutaneously with MCT, followed by the continuous administration of NCP-2454, an ACE2 activator, using osmotic pumps. Pulmonary arterial compliance was monitored every week until 4 weeks post-injection (wpi). RVH and lung remodeling was evaluated using lung tissue at 4 wpi. RESULTS: NCP-2454 upregulated the production of Ang-(1-7) when incubated with ACE2 and Ang II. Notably, a continuous infusion of NCP-2454 significantly improved pulmonary arterial compliance, right ventricular systolic pressure, and RVH in MCT-treated rats. Interestingly, NCP-2454 increased the relative expression of ACE2 and MAS mRNA in lung tissue, especially in MCT-treated rats. In addition, the compound inhibited the MCT-induced overexpression of transforming growth factor ß, phosphorylation of signal transducer and activator of transcription-3 (STAT3), and interleukin-6 production. The compound also restored the expression of caveolin-1 (Cav-1), which negatively regulates the Janus kinase-STAT signaling cascade. CONCLUSIONS: NCP-2454 prevented MCT-induced PH by suppressing intracellular inflammatory cascades, an upstream molecular change of which is the disruption of Cav-1 expression.


Asunto(s)
Caveolina 1/metabolismo , Hipertensión Pulmonar/prevención & control , Oxazoles/uso terapéutico , Peptidil-Dipeptidasa A/efectos de los fármacos , Pirimidinas/uso terapéutico , Enzima Convertidora de Angiotensina 2 , Animales , Evaluación Preclínica de Medicamentos , Activación Enzimática/efectos de los fármacos , Retroalimentación Fisiológica/efectos de los fármacos , Ventrículos Cardíacos/efectos de los fármacos , Hipertensión Pulmonar/inducido químicamente , Hipertensión Pulmonar/metabolismo , Hipertrofia Ventricular Derecha/prevención & control , Quinasas Janus/metabolismo , Masculino , Monocrotalina , Oxazoles/farmacología , Peptidil-Dipeptidasa A/metabolismo , Pirimidinas/farmacología , Ratas Sprague-Dawley , Factores de Transcripción STAT/metabolismo , Factor de Crecimiento Transformador beta/metabolismo
17.
Nanomedicine ; 11(1): 229-38, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25229542

RESUMEN

Multi-modal thermo-sensitive polymer-modified liposomes (MTPLs) containing an anticancer drug, MR contrast agent, and fluorescent dye have been investigated as "theranostic" nanodevices that can be used to monitor drug delivery in cancer therapy. Here, we measured the physical characteristics of MTPLs, observed the dynamics of MTPLs in vivo, visualized heat-triggered drug release using MRI, and evaluated the treatment effects of the MTPLs with and without heating. In vitro experiments demonstrated that the MTPLs released drugs at temperatures above 41°C. In vivo MTPLs accumulated in tumor tissue, with the accumulation maximized for 4-12hours. MR signal in the tumor was significantly elevated after mild heating for 15 minutes, indicating release of the contrast agent from the MTPLs was facilitated by heat-triggering. Tumor size after treatment with MTPLs and heating was significantly smaller than those of the control groups. In conclusion, MTPLs with MRI are useful for low-invasive cancer theranostics.


Asunto(s)
Antineoplásicos/química , Sistemas de Liberación de Medicamentos , Liposomas/química , Neoplasias/patología , Polímeros/química , Animales , Línea Celular Tumoral , Medios de Contraste/química , Doxorrubicina/administración & dosificación , Femenino , Colorantes Fluorescentes/química , Calor , Imagen por Resonancia Magnética , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Nanomedicina , Nanopartículas/química , Trasplante de Neoplasias , Neoplasias/metabolismo
18.
Rheumatology (Oxford) ; 53(7): 1219-28, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24599914

RESUMEN

OBJECTIVE: The gamma-aminobutyric acid type B receptors (GABAR(B)) are G-protein coupled receptors for GABA, the main inhibitory neurotransmitter in the brain. We identified GABAR(B) subunits as candidate antigens in patients with SLE using a random peptide display library. The aim of this study was to investigate the possible link between anti-GABAR(B) antibodies and disease activity and NPSLE. METHODS: ELISA was performed with recombinant proteins of GABAR(B1b) and GABAR(B2) on serum samples from patients with SLE (n = 88), scleroderma (n = 20), myositis (n = 20) or vasculitis (n = 20) as well as healthy subjects (n = 20). Cerebrospinal fluid (CSF) from 23 patients with SLE was also examined. RESULTS: Autoantibodies to GABAR(Bs) were exclusive to patients with SLE (P < 0.001) and positively associated with SLEDAI (anti-GABAR(B1b), P = 0.001; anti-GABAR(B2), P < 0.001). Of note, autoantibodies were positively linked with NPSLE (anti-GABAR(B1b), P = 0.02; anti-GABAR(B2), P = 0.03). Moreover, anti-GABAR(Bs) was detected in 61.5% of CSF samples from patients with active NPSLE, a frequency that was significantly higher than that for patients with non-SLE syndromes. CONCLUSION: Anti-GABAR(B) antibodies could represent novel candidate markers for disease activity and NPSLE.


Asunto(s)
Autoanticuerpos/sangre , Vasculitis por Lupus del Sistema Nervioso Central/diagnóstico , Receptores de GABA-B/inmunología , Adulto , Anciano , Autoanticuerpos/líquido cefalorraquídeo , Biomarcadores/sangre , Biomarcadores/líquido cefalorraquídeo , Estudios de Casos y Controles , Femenino , Humanos , Vasculitis por Lupus del Sistema Nervioso Central/inmunología , Vasculitis por Lupus del Sistema Nervioso Central/metabolismo , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad
19.
PLoS One ; 19(1): e0296502, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38166062

RESUMEN

BACKGROUND: Despite effective antiretroviral therapy, patients with human immunodeficiency virus type-1 (HIV) suffer from a high frequency of malignancies, but related risk factors remain elusive. Here, we focused on blood-circulating viral protein R (Vpr) of HIV, which induces proinflammatory cytokine production and genotoxicity by exogenous functions. METHODS AND FINDINGS: A total 404 blood samples of HIV patients comprising of 126 patients with malignancies (tumor group) and 278 patients without malignancies (non-tumor group), each of 96 samples was first selected by one-to-one propensity score matching. By a detergent-free enzyme-linked immunosorbent assays (detection limit, 3.9 ng/mL), we detected Vpr at a higher frequency in the matched tumor group (56.3%) than in the matched non-tumor group (39.6%) (P = 0.030), although there was no different distribution of Vpr levels (P = 0.372). We also detected anti-Vpr immunoglobulin (IgG), less frequently in the tumor group compared with the tumor group (22.9% for tumor group vs. 44.8% for non-tumor group, P = 0.002), and the proportion of patients positive for Vpr but negative of anti-Vpr IgG was significantly higher in the tumor group than in the non-tumor group (38.6% vs. 15.6%, respectively, P < 0.001). Additionally, Interleukin-6 (IL-6), the levels of which were high in HIV-1 infected patients (P < 0.001) compared to non-HIV-infected individuals, was significantly higher in advanced cases of tumors (P < 0.001), and IL-6 level was correlated with Vpr in the non-tumor group (P = 0.010). Finally, multivariate logistic regression analysis suggested a positive link of Vpr with tumor occurrence in HIV patients (P = 0.002). CONCLUSION: Vpr and IL-6 could be risk factors of HIV-1 associated malignancies, and it would be importance to monitor these molecules for well managing people living with HIV-1.


Asunto(s)
Infecciones por VIH , VIH-1 , Neoplasias , Humanos , Interleucina-6 , Productos del Gen vpr del Virus de la Inmunodeficiencia Humana , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/metabolismo , Estudios de Cohortes , Factores de Riesgo , Inmunoglobulina G
20.
Retrovirology ; 10: 21, 2013 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-23432899

RESUMEN

BACKGROUND: The prevention of persistent human immunodeficiency virus type 1 (HIV-1) infection requires the clarification of the mode of viral transduction into resting macrophages. Recently, DNA double-strand breaks (DSBs) were shown to enhance infection by D64A virus, which has a defective integrase catalytic activity (IN-CA). However, the mechanism by which DSBs upregulate viral transduction was unclear. Here we analyzed the roles of DSBs during IN-CA-independent viral transduction into macrophages. RESULTS: We used cellular systems with rare-cutting endonucleases and found that D64A virus integrated efficiently into the sites of artificially induced DSBs. This IN-CA-independent viral transduction was blocked by an inhibitor of ataxia telangiectasia mutated protein (ATM) but was resistant to raltegravir (RAL), an inhibitor of integrase activity during strand transfer. Moreover, Vpr, an accessory gene product of HIV-1, induced DSBs in resting macrophages and significantly enhanced the rate of IN-CA-independent viral transduction into macrophages with concomitant production of secondary viruses. CONCLUSION: DSBs contribute to the IN-CA-independent viral infection of macrophages, which is resistant to RAL. Thus, the ATM-dependent cellular pathway and Vpr-induced DNA damage are novel targets for preventing persistent HIV-1 infection.


Asunto(s)
Daño del ADN/fisiología , Integrasa de VIH/metabolismo , VIH-1/patogenicidad , Macrófagos/virología , Integración Viral/fisiología , Proteínas de la Ataxia Telangiectasia Mutada , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Línea Celular , Roturas del ADN de Doble Cadena , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Farmacorresistencia Viral , Células HEK293 , Integrasa de VIH/genética , VIH-1/enzimología , VIH-1/fisiología , Humanos , Inhibidores de Integrasa/farmacología , Macrófagos/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Pirrolidinonas/farmacología , Raltegravir Potásico , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/metabolismo , Integración Viral/genética , Productos del Gen vpr del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen vpr del Virus de la Inmunodeficiencia Humana/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA