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1.
Avian Pathol ; 53(1): 14-32, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38009206

RESUMO

RESEARCH HIGHLIGHTS: A thermostable, safe, and effective NDV GVII recombinant vaccine was generated.Fusion gene replacement with GVII did not affect GI K148/08 virus thermostability.Strain rK148/GVII-F provided adequate protection against a lethal NDV challenge.Oropharyngeal shedding was significantly reduced on post-challenge days 5 and 7.


Assuntos
Doença de Newcastle , Doenças das Aves Domésticas , Vacinas Virais , Animais , Galinhas , Vírus da Doença de Newcastle/genética , Vacinas Atenuadas , Genótipo , Vacinas Sintéticas , Doenças das Aves Domésticas/prevenção & controle , Anticorpos Antivirais
2.
Avian Pathol ; 52(2): 100-107, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36377478

RESUMO

In 2020, the Y280-lineage H9N2 low-pathogenic avian influenza virus (LPAIV) was introduced into South Korea for the first time. Current vaccines are focused on the control of Y439-like viruses; however, there are continuous reports of decrease in egg production and secondary infections caused by Y280-lineage H9N2 LPAI infection in chickens. Therefore, there is an urgent need to develop effective novel vaccines against Y280-lineage H9N2 LPAI. Most commercialized avian influenza vaccines are oil-adjuvanted inactivated vaccines, which are labour-intensive to administer and require higher dosage. In this study, rK148/Y280-HA, a novel recombinant Newcastle disease virus (NDV) vectored vaccine against Y280-lineage H9N2 LPAI, was developed and evaluated using two mass-applicable administration methods, spray vaccination and drinking water vaccination. Regardless of low serum antibody haemagglutination inhibition titres against NDV and Y280-lineage H9N2 LPAI after applying the rK148/Y280-HA vaccine, vaccination with either administration method protected chickens against virulent NDV and Y280-lineage H9N2 LPAIV after the challenge. Taken together, these results indicate that the rK148/Y280 vaccine can be administered using facile mass-application methods to provide protection against the Y280-lineage LPAI.RESEARCH HIGHLIGHTS NDV vectored vaccine harbouring Y280-lineage H9N2 HA protein was successfully generated.NDV vectored vaccine provides protection against NDV.NDV vectored vaccine with H9N2 HA protects against homologous H9N2 LPAIV.


Assuntos
Vírus da Influenza A Subtipo H9N2 , Vacinas contra Influenza , Influenza Aviária , Doença de Newcastle , Vacinas Virais , Animais , Vírus da Doença de Newcastle , Hemaglutininas , Galinhas , Anticorpos Antivirais , Replicação Viral
3.
Sensors (Basel) ; 23(21)2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37960462

RESUMO

Due to the immutability of blockchain, the integration with big-data systems creates limitations on redundancy, scalability, cost, and latency. Additionally, large amounts of invaluable data result in the waste of energy and storage resources. As a result, the demand for data deletion possibilities in blockchain has risen over the last decade. Although several prior studies have introduced methods to address data modification features in blockchain, most of the proposed systems need shorter deletion delays and security requirements. This study proposes a novel blockchain architecture called Unlichain that provides data-modification features within public blockchain architecture. To achieve this goal, Unlichain employed a new indexing technique that defines the deletion time for predefined lifetime data. The indexing technique also enables the deletion possibility for unknown lifetime data. Unlichain employs a new metadata verification consensus among full and meta nodes to avoid delays and extra storage usage. Moreover, Unlichain motivates network nodes to include more transactions in a new block, which motivates nodes to scan for expired data during block mining. The evaluations proved that Unlichain architecture successfully enables instant data deletion while the existing solutions suffer from block dependency issues. Additionally, storage usage is reduced by up to 10%.

4.
Sensors (Basel) ; 23(21)2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37960388

RESUMO

Radiator reliability is crucial in environments characterized by high temperatures and friction, where prompt interventions are often required to prevent system failures. This study introduces a proactive approach to radiator fault diagnosis, leveraging the integration of the Gaussian Mixture Model and Long-Short Term Memory autoencoders. Vibration signals from radiators were systematically collected through randomized durability vibration bench tests, resulting in four operating states-two normal, one unknown, and one faulty. Time-domain statistical features of these signals were extracted and subjected to Principal Component Analysis to facilitate efficient data interpretation. Subsequently, this study discusses the comparative effectiveness of the Gaussian Mixture Model and Long Short-Term Memory in fault detection. Gaussian Mixture Models are deployed for initial fault classification, leveraging their clustering capabilities, while Long-Short Term Memory autoencoders excel in capturing time-dependent sequences, facilitating advanced anomaly detection for previously unencountered faults. This alignment offers a potent and adaptable solution for radiator fault diagnosis, particularly in challenging high-temperature or high-friction environments. Consequently, the proposed methodology not only provides a robust framework for early-stage fault diagnosis but also effectively balances diagnostic capabilities during operation. Additionally, this study presents the foundation for advancing reliability life assessment in accelerated life testing, achieved through dynamic threshold adjustments using both the absolute log-likelihood distribution of the Gaussian Mixture Model and the reconstruction error distribution of the Long-Short Term Memory autoencoder model.

5.
J Integr Plant Biol ; 63(8): 1505-1520, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34051041

RESUMO

Influenza epidemics frequently and unpredictably break out all over the world, and seriously affect the breeding industry and human activity. Inactivated and live attenuated viruses have been used as protective vaccines but exhibit high risks for biosafety. Subunit vaccines enjoy high biosafety and specificity but have a few weak points compared to inactivated virus or live attenuated virus vaccines, especially in low immunogenicity. In this study, we developed a new subunit vaccine platform for a potent, adjuvant-free, and multivalent vaccination. The ectodomains of hemagglutinins (HAs) of influenza viruses were expressed in plants as trimers (tHAs) to mimic their native forms. tHAs in plant extracts were directly used without purification for binding to inactivated Lactococcus (iLact) to produce iLact-tHAs, an antigen-carrying bacteria-like particle (BLP). tHAs BLP showed strong immune responses in mice and chickens without adjuvants. Moreover, simultaneous injection of two different antigens by two different formulas, tHAH5N6 + H9N2 BLP or a combination of tHAH5N6 BLP and tHAH9N2 BLP, led to strong immune responses to both antigens. Based on these results, we propose combinations of plant-based antigen production and BLP-based delivery as a highly potent and cost-effective platform for multivalent vaccination for subunit vaccines.


Assuntos
Adjuvantes Imunológicos/farmacologia , Vírus da Influenza A Subtipo H9N2/imunologia , Vacinas contra Influenza/imunologia , Lactococcus/virologia , Nicotiana/genética , Vacinas Combinadas/imunologia , Animais , Antígenos Virais/imunologia , Galinhas/imunologia , Retículo Endoplasmático/metabolismo , Hemaglutininas/química , Hemaglutininas/metabolismo , Imunidade/efeitos dos fármacos , Imunização , Camundongos , Extratos Vegetais/isolamento & purificação , Plantas Geneticamente Modificadas , Domínios Proteicos , Multimerização Proteica
6.
Sensors (Basel) ; 20(18)2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32899751

RESUMO

This study focuses on driver-behavior identification and its application to finding embedded solutions in a connected car environment. We present a lightweight, end-to-end deep-learning framework for performing driver-behavior identification using in-vehicle controller area network (CAN-BUS) sensor data. The proposed method outperforms the state-of-the-art driver-behavior profiling models. Particularly, it exhibits significantly reduced computations (i.e., reduced numbers both of floating-point operations and parameters), more efficient memory usage (compact model size), and less inference time. The proposed architecture features depth-wise convolution, along with augmented recurrent neural networks (long short-term memory or gated recurrent unit), for time-series classification. The minimum time-step length (window size) required in the proposed method is significantly lower than that required by recent algorithms. We compared our results with compressed versions of existing models by applying efficient channel pruning on several layers of current models. Furthermore, our network can adapt to new classes using sparse-learning techniques, that is, by freezing relatively strong nodes at the fully connected layer for the existing classes and improving the weaker nodes by retraining them using data regarding the new classes. We successfully deploy the proposed method in a container environment using NVIDIA Docker in an embedded system (Xavier, TX2, and Nano) and comprehensively evaluate it with regard to numerous performance metrics.

7.
Sensors (Basel) ; 16(6)2016 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-27294941

RESUMO

Sensor fusion techniques have made a significant contribution to the success of the recently emerging mobile applications era because a variety of mobile applications operate based on multi-sensing information from the surrounding environment, such as navigation systems, fitness trackers, interactive virtual reality games, etc. For these applications, the accuracy of sensing information plays an important role to improve the user experience (UX) quality, especially with gyroscopes and accelerometers. Therefore, in this paper, we proposed a novel mechanism to resolve the gyro drift problem, which negatively affects the accuracy of orientation computations in the indirect Kalman filter based sensor fusion. Our mechanism focuses on addressing the issues of external feedback loops and non-gyro error elements contained in the state vectors of an indirect Kalman filter. Moreover, the mechanism is implemented in the device-driver layer, providing lower process latency and transparency capabilities for the upper applications. These advances are relevant to millions of legacy applications since utilizing our mechanism does not require the existing applications to be re-programmed. The experimental results show that the root mean square errors (RMSE) before and after applying our mechanism are significantly reduced from 6.3 × 10(-1) to 5.3 × 10(-7), respectively.

8.
Chemosphere ; 361: 142539, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38844110

RESUMO

The feasibility of using hexagonal boron nitride (h-BN) to treat heavy metal Cr(III) from model contaminated groundwater was evaluated in this study by adsorption experiments and characterizations. To the best of our knowledge, this study is the first attempt to conduct the adsorption of Cr(III) by h-BN under various experimental conditions such as exposure time, ratio of adsorbates and adsorbents, solution pH, background ions with different ionic strength, and the presence of humic acids (HA) in model contaminated groundwater. The optimized h-BN showed excellent maximum adsorption capacity (i.e., 177 mg ∙ g-1) when the concentrations of Cr(III) and h-BN were 10 and 10 mg ∙ L-1, respectively. Subsequently, we confirmed there was a negligible change in the adsorption performance of Cr(III) by h-BN in the presence of co-ions (i.e., K and Mg) in concentrations in a range from 50 to 1000 mg ∙ L-1. Furthermore, the adsorption performance of Cr(III) gradually improved with HA concentrations from 2.5 to 25 mg ∙ L-1. Interestingly, the maximum adsorption performance of Cr(III) by both HA and h-BN increased until 500 mg ∙ g-1 in the presence of 25 mg ∙ L-1 HA. The adsorption mechanism was clarified by Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy. Additionally, we successfully confirmed that h-BN could be reused until five cycles. On the basis of the adsorption performance results and characterizations, h-BN can be utilized as an efficient and practical adsorbent to treat Cr(III) in groundwater treatment.


Assuntos
Compostos de Boro , Cromo , Água Subterrânea , Poluentes Químicos da Água , Adsorção , Cromo/química , Água Subterrânea/química , Poluentes Químicos da Água/química , Compostos de Boro/química , Purificação da Água/métodos , Substâncias Húmicas/análise , Concentração de Íons de Hidrogênio , Íons/química
9.
J Hazard Mater ; 469: 134072, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38522201

RESUMO

Acid leaching has been widely applied to treat contaminated soil, however, it contains several inorganic pollutants. The decommissioning of nuclear power plants introduces radioactive and soluble U(VI), a substance posing chemical toxicity to humans. Our investigation sought to ascertain the efficacy of hexagonal boron nitride (h-BN), an highly efficient adsorbent, in treating U(VI) in wastewater. The adsorption equilibrium of U(VI) by h-BN reached saturation within a mere 2 h. The adsorption of U(VI) by h-BN appears to be facilitated through electrostatic attraction, as evidenced by the observed impact of pH variations, acidic agents (i.e., HCl or H2SO4), and the presence of background ions on the adsorption performance. A reusability test demonstrated the successful completion of five cycles of adsorption/desorption, relying on the surface characteristics of h-BN as influenced by solution pH. Based on the experimental variables of initial U(VI) concentration, exposure time, temperature, pH, and the presence of background ions/organic matter, a feature importance analysis using random forest (RF) was carried out to evaluate the correlation between performances and conditions. To the best of our knowledge, this study is the first attempt to conduct the adsorption of U(VI) generated from real contaminated soil by h-BN, followed by interpretation of the correlation between performance and conditions using RF. Lastly, a. plausible adsorption mechanism between U(VI) and h-BN was explained based on the experimental results, characterizations, and a. comparison with previous adsorption studies on the removal of heavy metals by h-BN.

10.
Vaccine ; 42(18): 3756-3767, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38724417

RESUMO

A Newcastle disease virus (NDV)-vectored vaccine expressing clade 2.3.4.4b H5 Hemagglutinin was developed and assessed for efficacy against H5N1 highly pathogenic avian influenza (HPAI) in specific pathogen-free (SPF) chickens, broilers, and domestic ducks. In SPF chickens, the live recombinant NDV-vectored vaccine, rK148/22-H5, achieved complete survival against HPAI and NDV challenges and significantly reduced viral shedding. Notably, the live rK148/22-H5 vaccine conferred good clinical protection in broilers despite the presence of maternally derived antibodies. Good clinical protection was observed in domestic ducks, with decreased viral shedding. It demonstrated complete survival and reduced cloacal viral shedding when used as an inactivated vaccine from SPF chickens. The rK148/22-H5 vaccine is potentially a viable and supportive option for biosecurity measure, effectively protecting in chickens against the deadly clade 2.3.4.4b H5 HPAI and NDV infections. Furthermore, it aligns with the strategy of Differentiating Infected from Vaccinated Animals (DIVA).


Assuntos
Anticorpos Antivirais , Galinhas , Patos , Glicoproteínas de Hemaglutininação de Vírus da Influenza , Virus da Influenza A Subtipo H5N1 , Influenza Aviária , Vírus da Doença de Newcastle , Vacinas de Produtos Inativados , Vacinas Sintéticas , Eliminação de Partículas Virais , Animais , Galinhas/imunologia , Influenza Aviária/prevenção & controle , Influenza Aviária/imunologia , Vírus da Doença de Newcastle/imunologia , Vírus da Doença de Newcastle/genética , Virus da Influenza A Subtipo H5N1/imunologia , Virus da Influenza A Subtipo H5N1/genética , Virus da Influenza A Subtipo H5N1/patogenicidade , Patos/virologia , Patos/imunologia , Vacinas de Produtos Inativados/imunologia , Vacinas de Produtos Inativados/administração & dosagem , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/sangue , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vacinas contra Influenza/imunologia , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/genética , Organismos Livres de Patógenos Específicos , Vacinas Atenuadas/imunologia , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/genética , Doenças das Aves Domésticas/prevenção & controle , Doenças das Aves Domésticas/virologia , Doenças das Aves Domésticas/imunologia , Doença de Newcastle/prevenção & controle , Doença de Newcastle/imunologia , Vacinas Virais/imunologia , Vacinas Virais/administração & dosagem , Vacinas Virais/genética
11.
Vaccine ; 41(33): 4787-4797, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37355454

RESUMO

Coronavirus disease 2019 (Covid-19) caused by the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) became a pandemic, causing significant burden on public health worldwide. Although the timely development and production of mRNA and adenoviral vector vaccines against SARS-CoV-2 have been successful, issues still exist in vaccine platforms for wide use and production. With the potential for proliferative capability and heat stability, the Newcastle disease virus (NDV)-vectored vaccine is a highly economical and conceivable candidate for treating emerging diseases. In this study, a recombinant NDV-vectored vaccine expressing the spike (S) protein of SARS-CoV-2, rK148/beta-S, was developed and evaluated for its efficacy against SARS-CoV-2 in K18-hACE-2 transgenic mice. Intramuscular vaccination with low dose (106.0 EID50) conferred a survival rate of 76 % after lethal challenge of a SARS-CoV-2 beta (B.1.351) variant. When administered with a high dose (107.0 EID50), vaccinated mice exhibited 100 % survival rate and reduced lung viral load against both beta and delta variants (B.1.617.2). Together with the protective immunity, rK148/beta-S is an accessible and cost-effective SARS-CoV-2 vaccine.


Assuntos
COVID-19 , Vacinas Virais , Camundongos , Animais , Humanos , COVID-19/prevenção & controle , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/genética , Vacinas contra COVID-19 , Vírus da Doença de Newcastle/genética , Camundongos Transgênicos , Vacinas Virais/genética , Anticorpos Antivirais , Anticorpos Neutralizantes
12.
Cells ; 10(11)2021 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-34831339

RESUMO

Apoptotic cells generated during development and for tissue homeostasis are swiftly and continuously removed by phagocytes via a process called efferocytosis. Efficient efferocytosis can be achieved via transcriptional modulation in phagocytes that have engulfed apoptotic cells. However, such modulation and its effect on efferocytosis are not completely understood. Here, we report that phagocytes are recruited to apoptotic cells being cleared through the Mcp-1-Ccr2 axis, which facilitates clearance of apoptotic cells. We identified Mcp-1 as a modulated transcript using a microarray and found that Mcp-1 secretion was augmented in phagocytes engulfing apoptotic cells. This augmented Mcp-1 secretion was impaired by blocking phagolysosomal degradation of apoptotic cells. Conditioned medium from wild type (WT) phagocytes promoted cell migration, but that from Mcp-1-/- phagocytes did not. In addition, blockade of Ccr2, the receptor for Mcp-1, abrogated cell migration to conditioned medium from phagocytes incubated with apoptotic cells. The intrinsic efferocytosis activity of Mcp-1-/- and Ccr2-/- phagocytes was unaltered, but clearance of apoptotic cells was less efficient in the peritoneum of Mcp-1-/- and Ccr2-/- mice than in that of WT mice because fewer Ccr2-positive phagocytes were recruited. Taken together, our findings demonstrate a mechanism by which not only apoptotic cells but also phagocytes induce chemoattraction to recruit phagocytes to sites where apoptotic cells are cleared for efficient efferocytosis.


Assuntos
Quimiocina CCL2/metabolismo , Quimiotaxia , Fagócitos/citologia , Fagocitose , Receptores CCR2/metabolismo , Transdução de Sinais , Ácidos/metabolismo , Animais , Apoptose , Meios de Cultivo Condicionados/farmacologia , Lisossomos/metabolismo , Camundongos Endogâmicos C57BL
13.
Healthcare (Basel) ; 9(6)2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34199705

RESUMO

We evaluated the benefits of the MotionFree algorithm through phantom and patient studies. The various sizes of phantom and vacuum vials were linked to RPM moving with or without MotionFree application. A total of 600 patients were divided into six groups by breathing protocols and CT scanning time. Breathing protocols were applied as follows: (a) patients who underwent scanning without any breathing instructions; (b) patients who were instructed to hold their breath after expiration during CT scan; and (c) patients who were instructed to breathe naturally. The length of PET/CT misregistration was measured and we defined the misregistration when it exceeded 10 mm. In the phantom tests, the images produced by the MotionFree algorithm were observed to have excellent agreement with static images. There were significant differences in PET/CT misregistration according to CT scanning time and each breathing protocol. When applying the type (c) protocol, decreasing the CT scanning time significantly reduced the frequency and length of misregistrations (p < 0.05). The MotionFree application is able to correct respiratory motion artifacts and to accurately quantify lesions. The shorter time of CT scan can reduce the frequency, and the natural breathing protocol also decreases the lengths of misregistrations.

14.
Cells ; 10(10)2021 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-34685684

RESUMO

Swift and continuous phagocytosis of apoptotic cells can be achieved by modulation of calcium flux in phagocytes. However, the molecular mechanism by which apoptotic cells modulate calcium flux in phagocytes is incompletely understood. Here, using biophysical, biochemical, pharmaceutical, and genetic approaches, we show that apoptotic cells induced the Orai1-STIM1 interaction, leading to store-operated calcium entry (SOCE) in phagocytes through the Mertk-phospholipase C (PLC) γ1-inositol 1,4,5-triphosphate receptor (IP3R) axis. Apoptotic cells induced calcium release from the endoplasmic reticulum, which led to the Orai1-STIM1 association and, consequently, SOCE in phagocytes. This association was attenuated by masking phosphatidylserine. In addition, the depletion of Mertk, which indirectly senses phosphatidylserine on apoptotic cells, reduced the phosphorylation levels of PLCγ1 and IP3R, resulting in attenuation of the Orai1-STIM1 interaction and inefficient SOCE upon apoptotic cell stimulation. Taken together, our observations uncover the mechanism of how phagocytes engulfing apoptotic cells elevate the calcium level.


Assuntos
Apoptose , Cálcio/metabolismo , Proteína ORAI1/metabolismo , Fagócitos/citologia , Fagócitos/metabolismo , Molécula 1 de Interação Estromal/metabolismo , Animais , Endocitose , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Células NIH 3T3 , Fosfolipase C gama/metabolismo , Ligação Proteica , Células RAW 264.7 , Transdução de Sinais , c-Mer Tirosina Quinase/metabolismo
15.
Front Vet Sci ; 8: 616755, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34113668

RESUMO

Highly pathogenic avian influenza (HPAI) is considered as one of the most devastating poultry diseases. It is imperative to immediately report any known outbreaks to the World Organization for Animal Health. Early detection of infected birds is of paramount importance to control virus spread, thus minimizing the associated economic loss. In this study, thermal imaging camera devices were used to detect change in the maximum surface temperature (MST) of chickens (n = 5) and ducks (n = 2) as an early indicator of experimental HPAI infection. The MST of both chickens and ducks increased at least 24 h before the manifestation of clinical signs of HPAI infection, depending on the severity of the infection. The basal MST was recorded for broiler chickens housed under small pen and normal farm conditions without intentional infection. A threshold cutoff of MST was established based on the circadian rhythm of normal MST. This study suggests that thermal imaging of chickens and ducks is a promising tool to screen any potential HPAI-infected flock in order to expedite HPAI diagnosis.

16.
Front Vet Sci ; 8: 773715, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35187138

RESUMO

The H5 subtype highly pathogenic avian influenza virus (HPAIV) has been introduced to South Korea every 2 or 3 years via wild migratory waterfowls, causing devastating damages to the poultry industry. Although most damages and economic losses by HPAIV are focused on chicken layers, domestic ducks are known to play a major role in the farm-to-farm transmission. However, most HPAIV vaccine studies on poultry have been performed with oil-emulsion inactivated vaccines. In this study, we developed a live recombinant Newcastle disease virus (NDV)-vectored vaccine against H5 HPAIV (rK148/ES2-HA) using a previously established NDV vaccine strain (K148/08) isolated from a wild mallard duck. The efficacy of the vaccine when administered via the oculonasal route or as a spray was evaluated against lethal H5 HPAIV infection in domestic ducks and chickens. Oculonasal inoculation of the rK148/ES2-HA in chickens and ducks elicited antibody titers against HPAIV as early as 1 or 2 week after the single dose of vaccination, whereas spray vaccination in ducks elicited antibodies against HPAIV after the booster vaccination. The chickens and ducks vaccinated with rK148/ES2-HA showed high survival rates and low viral shedding after H5N6 HPAIV challenge. Collectively, vaccination with rK148/ES2-HA prevented lethal infection and decreased viral shedding in both chickens and ducks. The vaccine developed in this study could be useful in suppressing the viral shedding in H5 HPAIV outbreaks, with the ease of vaccine application and fast onset of immunity.

17.
Mol Cells ; 44(4): 214-222, 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33935042

RESUMO

Phosphatidylserine (PS), a negatively charged phospholipid exclusively located in the inner leaflet of the plasma membrane, is involved in various cellular processes such as blood coagulation, myoblast fusion, mammalian fertilization, and clearance of apoptotic cells. Proteins that specifically interact with PS must be identified to comprehensively understand the cellular processes involving PS. However, only a limited number of proteins are known to associate with PS. To identify PS-associating proteins, we performed a pulldown assay using streptavidin-coated magnetic beads on which biotin-linked PS was immobilized. Using this approach, we identified Hsd17b4, a peroxisomal protein, as a PS-associating protein. Hsd17b4 strongly associated with PS, but not with phosphatidylcholine or sphingomyelin, and the Scp-2-like domain of Hsd17b4 was responsible for this association. The association was disrupted by PS in liposomes, but not by free PS or the components of PS. In addition, translocation of PS to the outer leaflet of the plasma membrane enriched Hsd17b4 in peroxisomes. Collectively, this study suggests an unexpected role of PS as a regulator of the subcellular localization of Hsd17b4.


Assuntos
Proteína Multifuncional do Peroxissomo-2/metabolismo , Peroxissomos/metabolismo , Fosfatidilserinas/metabolismo , Animais , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos C57BL
18.
Genes Genomics ; 42(9): 979-986, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32648232

RESUMO

One of the key features of the plasma membrane is the asymmetrical distribution of phospholipids across it. Especially, phosphatidylserine (PS) exclusively locates on its inner leaflet. Thus, the exposure of PS on the surface of cells could function as a signal initiating various cellular processes such as phagocytosis of apoptotic cells called efferocytosis, blood clotting, muscle formation, and viral entry. Indeed, PS on apoptotic cells stimulates phagocytes to engulf them and functions as an essential ligand for efferocytosis. Due to the importance of PS in efferocytosis, the existence of the PS receptor had been conceived. However, the PS receptor had not been revealed for a long time. Thus, the first identification of the PS receptor was significant excitement. Tim-4, a member of the T cell immunoglobulin and mucin domain containing family of genes, was one of PS receptors which first identified and received the greatest attention due to its expression in macrophages and relevance to autoimmune and allergic diseases. This review will serve to provide a comprehensive overview of Tim proteins as PS receptors.


Assuntos
Proteínas de Membrana/metabolismo , Fosfatidilserinas/metabolismo , Apoptose/fisiologia , Humanos , Macrófagos/imunologia , Macrófagos/metabolismo , Proteínas de Membrana/fisiologia , Fagocitose/imunologia , Fagocitose/fisiologia , Receptores de Superfície Celular/metabolismo , Transdução de Sinais
19.
Cell Death Dis ; 11(7): 561, 2020 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-32703939

RESUMO

The phosphatidylserine (PS) receptor Tim-4 mediates phagocytosis of apoptotic cells by binding to PS exposed on the surface of these cells, and thus functions as a PS receptor for apoptotic cells. Some of PS receptors are capable of recognizing other molecules, such as LPS on bacteria, besides PS on apoptotic cells. However, it is unclear whether Tim-4 perceives other molecules like the PS receptors. Here, we report that Tim-4 facilitates the phagocytosis of exogenous particles as well as apoptotic cells. Similar to the process that occurs during Tim-4-mediated efferocytosis, the uptake of exogenous E. coli and S. aureus bioparticles was promoted by overexpression of Tim-4 on phagocytes, whereas phagocytosis of the bioparticles was reduced in Tim-4-deficient cells. A truncation mutant of Tim-4 lacking the cytoplasmic tail promoted phagocytosis of the particles, but a mutant lacking the IgV or the mucin domain failed to enhance phagocytosis. However, expression of Tim-4AAA (a mutant form of Tim-4 that does not bind phosphatidylserine and does not promote efferocytosis) still promoted phagocytosis. Tim-4-mediated phagocytosis was not blocked by expression of the phosphatidylserine-binding protein Anxa5. Furthermore, binding of lipopolysaccharide (LPS), which is found in the outer membrane of Gram-negative bacteria, was higher in Tim-4-overexpressing cells than in Tim-4-deficient cells. In summary, our study suggests that Tim-4 acts as a scavenger receptor and mediates phagocytosis of exogenous particles in a phosphatidylserine-independent manner.


Assuntos
Proteínas de Membrana/metabolismo , Fagocitose , Receptores Depuradores/metabolismo , Animais , Apoptose , Linhagem Celular , Escherichia coli/metabolismo , Proteínas de Membrana/química , Camundongos Endogâmicos C57BL , Fagócitos/metabolismo , Fosfatidilserinas/metabolismo , Staphylococcus aureus/metabolismo
20.
Cells ; 9(7)2020 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-32640697

RESUMO

Apoptotic cells expressing phosphatidylserine (PS) on their cell surface are directly or indirectly recognized by phagocytes through PS-binding proteins. The PS-binding protein Tim-4 secures apoptotic cells to phagocytes to facilitate the engulfment of apoptotic cells. However, the molecular mechanism by which Tim-4 transduces signals to phagocytes during Tim-4-mediated efferocytosis is incompletely understood. Here, we report that Tim-4 collaborates with Mertk during efferocytosis through a biochemical interaction with Mertk. Proximal localization between the two proteins in phagocytes was observed by immunofluorescence and proximal ligation assays. Physical association between Tim-4 and Mertk, which was mediated by an interaction between the IgV domain of Tim-4 and the fibronectin type-III domain of Mertk, was also detected with immunoprecipitation. Furthermore, the effect of Mertk on Tim-4-mediated efferocytosis was abolished by GST-MertkFnIII, a soluble form of the fibronectin type-III domain of Mertk that disrupts the interaction between Tim-4 and Mertk. Taken together, the results from our study suggest that a physical interaction between Tim-4 and Mertk is necessary for Mertk to enhance efferocytosis mediated by Tim-4.


Assuntos
Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , c-Mer Tirosina Quinase/química , c-Mer Tirosina Quinase/metabolismo , Animais , Domínio de Fibronectina Tipo III/genética , Domínio de Fibronectina Tipo III/fisiologia , Células HEK293 , Humanos , Immunoblotting , Imunoprecipitação , Proteínas de Membrana/genética , Camundongos , Camundongos Mutantes , Fagocitose/genética , Fagocitose/fisiologia , Ligação Proteica , c-Mer Tirosina Quinase/genética
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