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1.
Preprint en Inglés | bioRxiv | ID: ppbiorxiv-520799

RESUMEN

Serum titers of SARS-CoV-2 neutralizing antibodies (nAb) correlate well with protection from symptomatic COVID-19, but decay rapidly in the months following vaccination or infection. In contrast, measles-protective nAb titers are life-long after measles vaccination, possibly due to persistence of the live-attenuated virus in lymphoid tissues. We therefore sought to generate a live recombinant measles vaccine capable of driving high SARS-CoV-2 nAb responses. Since previous clinical testing of a live measles vaccine encoding a SARS-CoV-2 spike glycoprotein resulted in suboptimal anti-spike antibody titers, our new vectors were designed to encode prefusion-stabilized SARS-CoV-2 spike glycoproteins, trimerized via an inserted peptide domain and displayed on a dodecahedral miniferritin scaffold. Additionally, to circumvent the blunting of vaccine efficacy by preformed anti-measles antibodies, we extensively modified the measles surface glycoproteins. Comprehensive in vivo mouse testing demonstrated potent induction of high titer nAb in measles-immune mice and confirmed the significant incremental contributions to overall potency afforded by prefusion stabilization, trimerization, and miniferritin-display of the SARS-CoV-2 spike glycoprotein, and vaccine resurfacing. In animals primed and boosted with a MeV vaccine encoding the ancestral SARS-CoV-2 spike, high titer nAb responses against ancestral virus strains were only weakly cross-reactive with the omicron variant. However, in primed animals that were boosted with a MeV vaccine encoding the omicron BA.1 spike, antibody titers to both ancestral and omicron strains were robustly elevated and the passive transfer of serum from these animals protected K18-ACE2 mice from infection and morbidity after exposure to BA.1 and WA1/2020 strains. Our results demonstrate that antigen engineering can enable the development of potent measles-based SARS-CoV-2 vaccine candidates.

2.
Preprint en Inglés | bioRxiv | ID: ppbiorxiv-464660

RESUMEN

An orally active vaccine capable of boosting SARS-CoV-2 immune responses in previously infected or vaccinated individuals would help efforts to achieve and sustain herd immunity. Unlike mRNA-loaded lipid nanoparticles and recombinant replication-defective adenoviruses, replicating vesicular stomatitis viruses with SARS-CoV-2 spike glycoproteins (VSV-SARS2) were poorly immunogenic after intramuscular administration in clinical trials. Here, by G protein trans-complementation, we generated VSV-SARS2(+G) virions with expanded target cell tropism. Compared to parental VSV-SARS2, G-supplemented viruses were orally active in virus-naive and vaccine-primed cynomolgus macaques, powerfully boosting SARS-CoV-2 neutralizing antibody titers. Clinical testing of this oral VSV-SARS2(+G) vaccine is planned.

3.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-931226

RESUMEN

Suppression of cellular O-linked β-N-acetylglucosaminylation (O-GlcNAcylation) can repress prolifera-tion and migration of various cancer cells,which opens a new avenue for cancer therapy.Based on the regulation of insulin gene transcription,we designed a cell-based fluorescent reporter capable of sensing cellular O-GlcNAcylation in HEK293T cells.The fluorescent reporter mainly consists of a reporter (green fluorescent protein (GFP)),an internal reference (red fluorescent protein),and an operator (neuronal differentiation 1),which serves as a "sweet switch" to control GFP expression in response to cellular O-GlcNAcylation changes.The fluorescent reporter can efficiently sense reduced levels of cellular O-GlcNAcylation in several cell lines.Using the fluorescent reporter,we screened 120 natural products and obtained one compound,sesamin,which could markedly inhibit protein O-GlcNAcylation in HeLa and human colorectal carcinoma-116 cells and repress their migration in vitro.Altogether,the present study demonstrated the development of a novel strategy for anti-tumor drug screening,as well as for con-ducting gene transcription studies.

4.
Journal of Integrative Medicine ; (12): 110-123, 2017.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-346269

RESUMEN

The efficacy of traditional Chinese medicine (TCM) treatments for Western medicine (WM) diseases relies heavily on the proper classification of patients into TCM syndrome types. The authors developed a data-driven method for solving the classification problem, where syndrome types were identified and quantified based on statistical patterns detected in unlabeled symptom survey data. The new method is a generalization of latent class analysis (LCA), which has been widely applied in WM research to solve a similar problem, i.e., to identify subtypes of a patient population in the absence of a gold standard. A well-known weakness of LCA is that it makes an unrealistically strong independence assumption. The authors relaxed the assumption by first detecting symptom co-occurrence patterns from survey data and used those statistical patterns instead of the symptoms as features for LCA. This new method consists of six steps: data collection, symptom co-occurrence pattern discovery, statistical pattern interpretation, syndrome identification, syndrome type identification and syndrome type classification. A software package called Lantern has been developed to support the application of the method. The method was illustrated using a data set on vascular mild cognitive impairment.


Asunto(s)
Humanos , Recolección de Datos , Interpretación Estadística de Datos , Diagnóstico Diferencial , Medicina Tradicional China
5.
Journal of Integrative Medicine ; (12): 186-200, 2017.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-346260

RESUMEN

<p><b>OBJECTIVE</b>To treat patients with vascular mild cognitive impairment (VMCI) using traditional Chinese medicine (TCM), it is necessary to classify the patients into TCM syndrome types and to apply different treatments to different types. In this paper, we investigate how to properly carry out the classification for patients with VMCI aged 50 or above using a novel data-driven method known as latent tree analysis (LTA).</p><p><b>METHOD</b>A cross-sectional survey on VMCI was carried out in several regions in Northern China between February 2008 and February 2012 which resulted in a data set that involves 803 patients and 93 symptoms. LTA was performed on the data to reveal symptom co-occurrence patterns, and the patients were partitioned into clusters in multiple ways based on the patterns. The patient clusters were matched up with syndrome types, and population statistics of the clusters are used to quantify the syndrome types and to establish classification rules.</p><p><b>RESULTS</b>Eight syndrome types are identified: Qi deficiency, Qi stagnation, Blood deficiency, Blood stasis, Phlegm-dampness, Fire-heat, Yang deficiency, and Yin deficiency. The prevalence and symptom occurrence characteristics of each syndrome type are determined. Quantitative classification rules are established for determining whether a patient belongs to each of the syndrome types.</p><p><b>CONCLUSION</b>A solution for the TCM syndrome classification problem for patients with VMCI and aged 50 or above is established based on the LTA of unlabeled symptom survey data. The results can be used as a reference in clinic practice to improve the quality of syndrome differentiation and to reduce diagnosis variances across physicians. They can also be used for patient selection in research projects aimed at finding biomarkers for the syndrome types and in randomized control trials aimed at determining the efficacy of TCM treatments of VMCI.</p>

6.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-671770

RESUMEN

Objective: In China, doctors at TCM hospitals and clinics often divide patients with a Western medicine (WM) disease into several syndrome classes from the TCM perspective and treat patients in different classes using different principles. A key problem is how to carry out the classification properly. We propose an evidence-based ap-proach for solving the problem where evidence is obtained by analyzing unlabeled symptom data using latent tree models.Method: In previous work, we have shown how latent tree analysis of symptom data can be used to identify TCM syndrome classes among patients with a WM disease. In the paper, we investigate how to establish classification rules for distinguishing between the classes.Results: We have applied the method to a data set about Vascular Mild Cognitive Impairment that involves 93 symptoms and 803 patients. Nine syndrome types are identified, along with the corresponding classification rules. Conclusions: An evidence-based approach to the TCM patient classification prob-lem has been developed. The approach can be used to answer the following questions about a WM disease: What TCM syndrome classes are there? What are the sizes of the classes? What are the statistical characteristics of each class? How can one differentiate between the different classes?

7.
Biochem Biophys Res Commun ; 438(2): 427-32, 2013 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-23899520

RESUMEN

Intricate cross-talks exist among multiple post-translational modifications that play critical roles in various cellular events, such as the control of gene expression and regulation of protein function. Here, the cross-talk between O-GlcNAcylation and ubiquitination was investigated in HEK293T cells. By PCR array, 84 ubiquitination-related genes were explored in transcription level in response to the elevation of total protein O-GlcNAcylation due to over-expression of OGT, inhibition of OGA or GlcN treatment. Varied genes were transcriptionally regulated by using different method. But FBXW10, an F-box protein targeting specific proteins for ubiquitination, could be negatively regulated in all ways, suggesting its regulation by protein O-GlcNAcylation. By RT-PCR and Western blot analysis, it was found that FBXW10 could be sharply down-regulated in mRNA and protein level in GlcN-treated cells in a time-dependent way, in line with the enhancement of protein O-GlcNAcylation. It was also found that endogenous FBXW10 was modified by O-GlcNAc in HEK293T cells, implying O-GlcNAcylation might regulate FBXW10 in multiple levels. These findings indicate that O-GlcNAcylation is involved in the regulation of ubiquitination-related genes, and help us understand the cross-talk between O-GlcNAcylation and ubiquitination.


Asunto(s)
Proteínas F-Box/metabolismo , Regulación de la Expresión Génica , N-Acetilglucosaminiltransferasas/metabolismo , Transcripción Genética , Proteínas F-Box/genética , Perfilación de la Expresión Génica , Células HEK293 , Humanos , Plásmidos , Procesamiento Proteico-Postraduccional , ARN Mensajero/metabolismo , Ubiquitina/química , Ubiquitinación
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