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Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), emerged as a global outbreak in 2019, profoundly affecting both human health and the global economy. Various vaccine modalities were developed and commercialized to overcome this challenge, including inactivated vaccines, mRNA vaccines, adenovirus vector-based vaccines, and subunit vaccines. While intramuscular vaccines induce high IgG levels, they often fail to stimulate significant mucosal immunity in the respiratory system. We employed the Newcastle disease virus (NDV) vector expressing the spike protein of the SARS-CoV-2 Beta variant (rK148/beta-S), and evaluated the efficacy of intranasal vaccination with rK148/beta-S in K18-hACE2 transgenic mice. Intranasal vaccination with a low dose (106.0 EID50) resulted in an 86% survival rate after challenge with the SARS-CoV-2 Beta variant. Administration at a high dose (107.0 EID50) led to a reduction in lung viral load and 100% survival against the SARS-CoV-2 Beta and Delta variants. A high level of the SARS-CoV-2 spike-specific IgA was also induced in vaccinated mice lungs following the SARS-CoV-2 challenge. Our findings suggest that rK148/beta-S holds promise as an intranasal vaccine candidate that effectively induces mucosal immunity against SARS-CoV-2.
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Arterial macrophage cholesterol accumulation and impaired cholesterol efflux lead to foam cell formation and the development of atherosclerosis. Modified lipoproteins interact with toll-like receptors (TLR), causing an increased inflammatory response and altered cholesterol homeostasis. We aimed to determine the effects of TLR antagonists on cholesterol efflux and foam cell formation in human macrophages. Stimulated monocytes were treated with TLR antagonists (MIP2), and the cholesterol efflux transporter expression and foam cell formation were analyzed. The administration of MIP2 attenuated the foam cell formation induced by lipopolysaccharides (LPS) and oxidized low-density lipoproteins (ox-LDL) in stimulated THP-1 cells (p < 0.001). The expression of ATP-binding cassette transporters A (ABCA)-1, ABCG-1, scavenger receptor (SR)-B1, liver X receptor (LXR)-α, and peroxisome proliferator-activated receptor (PPAR)-γ mRNA and proteins were increased (p < 0.001) following MIP2 administration. A concentration-dependent decrease in the phosphorylation of p65, p38, and JNK was also observed following MIP2 administration. Moreover, an inhibition of p65 phosphorylation enhanced the expression of ABCA1, ABCG1, SR-B1, and LXR-α. TLR inhibition promoted the cholesterol efflux pathway by increasing the expression of ABCA-1, ABCG-1, and SR-B1, thereby reducing foam cell formation. Our results suggest a potential role of the p65/NF-kB/LXR-α/ABCA1 axis in TLR-mediated cholesterol homeostasis.
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Transportador 1 de Cassete de Ligação de ATP , Colesterol , Células Espumosas , Lipoproteínas LDL , Receptores X do Fígado , Receptores Toll-Like , Humanos , Células Espumosas/metabolismo , Células Espumosas/efeitos dos fármacos , Colesterol/metabolismo , Receptores X do Fígado/metabolismo , Receptores Toll-Like/metabolismo , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Transportador 1 de Cassete de Ligação de ATP/genética , Lipoproteínas LDL/metabolismo , Lipoproteínas LDL/farmacologia , PPAR gama/metabolismo , Células THP-1 , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Lipopolissacarídeos/farmacologia , Receptores Depuradores Classe B/metabolismo , Receptores Depuradores Classe B/genéticaRESUMO
KRAS plays a crucial role in regulating cell survival and proliferation and is one of the most commonly mutated oncogenes in human cancers. The novel KRASG12D inhibitor, MRTX1133, demonstrates promising antitumor efficacy in vitro and in vivo. However, the development of acquired resistance in treated patients presents a considerable challenge to sustained therapeutic effectiveness. In response to this challenge, we conducted site-specific mutagenesis screening to identify potential secondary mutations that could induce resistance to MRTX1133. We screened a range of KRASG12D variants harboring potential secondary mutations, and 44 representative variants were selected for in-depth validation of the pooled screening outcomes. We identified eight variants (G12D with V9E, V9W, V9Q, G13P, T58Y, R68G, Y96W, and Q99L) that exhibited substantial resistance, with V9W showing notable resistance, and downstream signaling analyses and structural modeling were conducted. We observed that secondary mutations in KRASG12D can lead to acquired resistance to MRTX1133 and BI-2865, a novel pan-KRAS inhibitor, in human cancer cell lines. This evidence is critical for devising new strategies to counteract resistance mechanisms and, ultimately, enhance treatment outcomes in patients with KRASG12D-mutant cancers.
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Resistencia a Medicamentos Antineoplásicos , Mutagênese Sítio-Dirigida , Mutação , Proteínas Proto-Oncogênicas p21(ras) , Humanos , Proteínas Proto-Oncogênicas p21(ras)/genética , Resistencia a Medicamentos Antineoplásicos/genética , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacosRESUMO
BACKGROUND/AIM: Phloretin is a natural flavonoid compound found in some plants, such as apples and pears, as well as in the bark of apple trees. Phloretin has been shown to have inhibitory effects on glucose transporters in cells and can potentially inhibit the growth of cancer cells. However, the mechanism by which phloretin regulates the expression of estrogen receptor alpha (ERα), a key transcription factor in breast cancer, is still unclear. This study investigated how phloretin affects the growth of ERα positive human breast cancer cells. MATERIALS AND METHODS: The growth of breast cancer cell lines, including MCF7 and T47D, was examined using cell proliferation and colony formation assays. Western blotting and semi-quantitative RT-PCR were used to examine protein and mRNA levels, respectively. Localization of cellular proteins was analyzed using subcellular fractionation. Transient transfection and reported gene assays were used to elucidate the impact of phloretin on cell proliferation and ERα transactivation. RESULTS: Phloretin decreased ERα expression at the mRNA and protein levels in MCF7 and T47D cells. It also inhibited the binding of ERα to the estrogen response element present in the promoter of target genes. Moreover, treatment with phloretin inhibited the expression of cyclin D1 and breast cancer marker gene pS2, which are known ERα target genes. Consequently, it inhibited the growth of ERα-positive human breast cancer cells. Furthermore, inhibition of breast cancer growth by phloretin was found to be mediated through both the ERα and ERK1/ERK2 pathways. CONCLUSION: Phloretin, a dihydrochalcone extracted from natural sources, exhibits the ability to regulate ERα function and suppress breast cancer cell proliferation.
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Neoplasias da Mama , Receptor alfa de Estrogênio , Humanos , Feminino , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Regulação para Baixo , Floretina/farmacologia , Proliferação de Células , RNA Mensageiro/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão GênicaRESUMO
Gas sensors are of great interest to portable and miniaturized sensing technologies with applications ranging from air quality monitoring to explosive detection and medical diagnostics, but the existing chemiresistive NO2 sensors still suffer from issues such as poor sensitivity, high operating temperature, and slow recovery. Herein, a high-performance NO2 sensors based on all-inorganic perovskite nanocrystals (PNCs) is reported, achieving room temperature operation with ultra-fast response and recovery time. After tailoring the halide composition, superior sensitivity of ≈67 at 8 ppm NO2 is obtained in CsPbI2 Br PNC sensors with a detection level down to 2 ppb, which outperforms other nanomaterial-based NO2 sensors. Furthermore, the remarkable optoelectronic properties of such PNCs enable dual-mode operation, i.e., chemiresistive and chemioptical sensing, presenting a new and versatile platform for advancing high-performance, point-of-care NO2 detection technologies.
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BACKGROUND: Patients with gastric cancer (GC) experience 2 characteristic treatment modalities (gastrectomy or endoscopic resection), which may induce heterogeneity in the risk of post-cancer treatment type 2 diabetes (T2D). We investigated differences in the risk for T2D development in survivors of GC according to the 2 treatment methods. STUDY DESIGN: This retrospective nationwide population-based cohort study included 14,646 patients with GC who underwent gastrectomy (n = 12,918) or endoscopic resection (n = 1,728). We enrolled patients who survived for at least 5 years after gastrectomy or endoscopic resection, had no history of diabetes, and had not received adjuvant chemotherapy. T2D risk was evaluated using Cox regression for the gastrectomy group and compared to that of the endoscopic resection group. Because of the competing risks of incident T2D and death, a competing risk regression was performed. RESULTS: After a median follow-up duration of 8.1 years, the incidence rates of T2D in the endoscopic resection group and gastrectomy group were 7.58 and 6.98 per 1,000 person-years, respectively. Patients undergoing gastrectomy showed a significantly higher risk for developing T2D than patients undergoing endoscopic resection (hazard ratio [HR], 1.37; 95% CI 1.18 to 1.58; p < 0.0001). In subgroup analyses, gastrectomy was associated with increased T2D risk in female patients (HR, 1.72; 95% CI 1.22 to 2.43; p = 0.030 for interaction). CONCLUSIONS: Among GC survivors, patients undergoing gastrectomy showed a 37% increased risk of T2D development compared to patients undergoing endoscopic resection. Subgroup analyses showed that T2D risk increased by up to 72% in female patients. These results provide insights for establishing screening and preventive strategies for GC survivors to prevent T2D according to different treatment modalities.
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Diabetes Mellitus Tipo 2 , Neoplasias Gástricas , Humanos , Feminino , Estudos Retrospectivos , Diabetes Mellitus Tipo 2/etiologia , Estudos de Coortes , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/diagnóstico , Gastrectomia/efeitos adversos , Gastrectomia/métodos , Resultado do TratamentoRESUMO
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.
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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 NeutralizantesRESUMO
Curcumin is a natural polyphenol that is extracted from the rhizomes of the turmeric plant (Curcuma longa), a member of the ginger family. It has been used for centuries in traditional Indian and Chinese medicine for its medicinal properties, including anti-inflammatory, antioxidant and antitumor effects. SVCT2 (Solute Carrier Family 23 Member 2, also known as SLC23A2) is a protein that plays a role in the transport of Vitamin C (Ascorbic Acid) into cells. SVCT2 plays an important role in tumor progression and metastasis, however, the molecular mechanisms of curcumin on SVCT2 have not been studied to date. Curcumin treatment inhibited proliferation and migration of cancer cells in a dose dependent manner. We found that curcumin reduced the expression of SVCT2 in cancer cells with a wild type p53, but not in those with a mutant type of p53. SVCT2 downregulation also reduced the MMP2 activity. Taken together, our results indicate that curcumin inhibited human cancer cell growth and migration by regulating SVCT2 through a downregulating p53. These findings provide new insights into the molecular mechanisms of curcumin's anticancer effects and potential therapeutic strategies for the treatment of metastatic migration.
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Curcumina , Neoplasias , Transportadores de Sódio Acoplados à Vitamina C , Humanos , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Curcumina/farmacologia , Regulação para Baixo , Neoplasias/tratamento farmacológico , Proteína Supressora de Tumor p53 , Transportadores de Sódio Acoplados à Vitamina C/efeitos dos fármacosRESUMO
Epithelial-to-mesenchymal transition (EMT) plays a critical role in the development and progression of lung cancer by promoting its invasiveness and metastasis. Using integrative analyses of the public lung cancer database, we found that the expression levels of the tight junction proteins, zonula occluden (ZO)-1 and ZO-2, were lower in lung cancer tissues, including both lung adenocarcinoma and lung squamous cell carcinoma than in normal lung tissues analyzed using The Cancer Genome Atlas (TCGA). Although the ectopic expression or knockdown of ZO-1 and ZO-2 did not affect the growth of lung cancer cells, they significantly regulated cell migration and invasion. When M0 macrophages were co-cultured with ZO-1 or ZO-2 knockdown Calu-1 cells, M2-like polarization was efficiently induced. Conversely, co-culture of M0 THP-1 cells with A549 cells stably expressing ZO-1 or ZO-2 significantly reduced M2 differentiation. We also identified G protein subunit alpha q (GNAQ) as a potential ZO-1- and ZO-2-specific activator through analysis of correlated genes with the TCGA lung cancer database. Our results suggest that the GNAQ-ZO-1/2 axis may play a tumor-suppressive role in lung cancer development and progression and highlight ZO-1 and ZO-2 as key EMT- and tumor microenvironment-suppressive proteins. These findings provide new insights for the development of targeted therapies for lung cancer.
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Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Junções Íntimas/metabolismo , Microambiente Tumoral/genética , Neoplasias Pulmonares/genética , Transição Epitelial-Mesenquimal/genética , Proteína da Zônula de Oclusão-1/genética , Proteína da Zônula de Oclusão-1/metabolismo , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/metabolismoRESUMO
BACKGROUND: In early 2020, the coronavirus 2019 (COVID-19) pandemic necessitated changes in social behavior to prevent its spread, including holding online classes, implementing social distancing, and allowing employees to telecommute. However, these changes have had a negative impact on people's sleep patterns and mental health, particularly for college students. OBJECTIVE: This study investigated the relationship between mental health and sleep quality according to the changes in lifestyle of college students in the periods before and after COVID-19. METHODS: The study subjects were 164 college students from Korea who had both face-to-face and non-face-to-face college experiences before and after COVID-19. The experiment was conducted using a Google survey, and the participants were recruited from the college community. The general features and lifestyle habits for the individuals were assessed using the AUDIT-K, Delphi method, KGHQ (General Mental Health Scale), and PSQI-K (Pittsburg Sleep Quality Index). RESULTS: The KGHQ and PSQI scores increased with the spread of COVID-19, which means that the mental health and sleep quality of college students deteriorated. 11 categories of variables were further investigated to evaluate changes in lifestyle, and the results indicate significant changes in the number of private meetings per week, monthly drinking, outdoor activity time, electronic device usage time, weekly food delivery, weekly late-night snacks, daily snacks, and daily coffee intake and no significant changes in exercise, smoking, and fast food intake. CONCLUSION: COVID-19 caused many changes in the lifestyle of college students, which adversely affected mental health and sleep.
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COVID-19 , Saúde Mental , Humanos , COVID-19/epidemiologia , Qualidade do Sono , Estudantes/psicologia , HábitosRESUMO
This quasi-experimental study used a cancer prevention program delivered by community health workers (CHWs) as an intervention to improve health literacy and increase screening uptake. The intervention group was educated by trained CHWs and received information about the nearby hospitals. After education, participants received telephone counseling once a month for 6 months. In the intervention group, CHWs met the participants individually and delivered the CD-ROM containing conversation scenarios with voice during the cancer screening test. The control group was provided educational materials related to breast and cervical cancers and a booklet containing information on mammography and Pap test. This study assessed the difference in mammography and Pap tests between the intervention and control groups. The results showed that the participants' knowledge improved, and the rate of cancer screening tests did not decrease in the intervention group. Therefore, it is necessary to develop and apply various programs that train CHWs and apply them to immigrant women to promote health-related behaviors under the health system that they are not familiar with while living in another country.
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Neoplasias da Mama , Emigrantes e Imigrantes , Neoplasias do Colo do Útero , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/prevenção & controle , China , Agentes Comunitários de Saúde , Detecção Precoce de Câncer/métodos , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Promoção da Saúde , Humanos , Programas de Rastreamento , República da Coreia , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/prevenção & controleRESUMO
BACKGROUND: The number of immigrant women in Korea is rapidly increasing. Immigrant women in Korea experience a host of health problems associated with living in a new country. Community health workers (CHWs) may be effective at delivering health promotion programs to vulnerable groups such as recent immigrants. PURPOSE: Qualitative analysis was performed to identify the main themes characterizing the experiences of CHWs in recommending and guiding preventive screening tests for immigrant women. METHODS: This focus-group study was designed to investigate the experiences and perceptions of CHWs. We conducted interviews with 15 Chinese immigrant women who served as CHWs in a cancer screening program. We asked questions about the attitudes and perceptions that CHWs had from their research experiences. Each interview was audio-recorded and transcribed verbatim. RESULTS: Three main themes emerged: (a) recognizing the need for preventive healthcare, (b) becoming the CHWs who help people to be healthy, and (c) challenges to overcome to make CHWs more active. The CHWs in this study were willing to help other Chinese immigrant women and to improve their competency to help more effectively. However, they recognized limitations on their ability to address problems when delivering a breast and cervical cancer screening program. CONCLUSIONS: When training CHWs for immigrants in Korea, frequent opportunities for consultation should be provided during program delivery to facilitate troubleshooting and help CHWs overcome challenges. A program that utilizes CHWs for various minority groups is needed.
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Emigrantes e Imigrantes , Neoplasias do Colo do Útero , China , Agentes Comunitários de Saúde , Detecção Precoce de Câncer , Feminino , Grupos Focais , Humanos , Pesquisa Qualitativa , República da Coreia , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/prevenção & controleRESUMO
Curcumin, a hydrophobic polyphenol of turmeric, has a variety of biological functions as an herbal supplement, but its poor gastric absorption rate is one of the major factors limiting its oral bioavailability. In the present study, we investigated the functional role of nanospheres loaded with curcumin (nCur) with regard to the motility of gut epithelial HCT116 cells and enterocyte migration along the crypt-villus axis. nCur significantly increased the motility of HCT116 cells and showed much higher migration efficacy than the curcumin. nCur stimulated the small GTPases Rac1 and the phosphorylation of protein kinase C, responsible for the distinctive activation of the mitogen-activated protein kinases. Interestingly, nCur significantly induced the expression of α-actinin, profilin-1, and filamentous (F)-actin as regulated by the phosphorylation of nuclear factor-kappa B during its promotion of cell migration. In mouse models of gut epithelial migration, treatment with nCur had an enhancing effect on the movement of enterocytes along the crypt-villus axis and the expression of cytoskeletal reorganization-related factors. These results indicate that nCur is a functional agent that promotes gut epithelial motility through F-actin-related migration signaling events.
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Actinas/metabolismo , Movimento Celular/efeitos dos fármacos , Curcumina/farmacologia , Células Epiteliais/metabolismo , Motilidade Gastrointestinal/efeitos dos fármacos , Nanosferas/uso terapêutico , Animais , Trato Gastrointestinal/metabolismo , Células HCT116 , Humanos , Masculino , Camundongos , NF-kappa B/metabolismo , Fosforilação , Proteína Quinase C/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
Generally, detoxification fabrics are defined as fabrics that remove or inhibit the production of toxic compounds, especially chemical warfare agents such as nerve gas agents. They are usually prepared using a complicated and time-consuming method. This study suggests a facile treatment method for preparing detoxification fabrics against nerve gas agents using polyethyleneimine and microwave curing. The detoxification properties of polyethyleneimine and microwave-treated polypropylene nonwoven fabric were evaluated using diisopropylfluoro-phosphate, which is a nerve agent simulant. The treated polypropylene fabric decontaminated 53.6% of diisopropylfluorophosphate (DFP) in 2 h at 32 °C, and the half-life of DFP on the surface of the treated fabric was 122 min. The result indicates that the treated fabric can act as a basic organocatalyst for the DFP hydrolysis and has a shorter half-life owing to the large number of amine groups. Therefore, the facile treatment method has the potential for use in the preparation of detoxification fabrics.
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Curcumin, a hydrophobic polyphenol of turmeric, has a variety of biological functions as a herbal supplement, but its poor gastric absorption rate is one of the major factors limiting its oral bioavailability. In the present study, we have investigated the functional role of a nanosphere loaded with curcumin (CN) during host cell death elicited by the Gram-negative bacterium V. vulnificus in human gastrointestinal epithelial HT-29 cells and an ileal-ligated mouse model. The recombinant protein (r) VvhA produced by V. vulnificus significantly reduced the viability of HT-29 cells. The cytotoxic effect of rVvhA was restored upon a treatment with CN (100 ng/mL), which had shown 1000-fold higher anti-apoptotic efficacy than curcumin. CN inhibited the phosphorylation of c-Src and PKC mediated by intracellular ROS responsible for the distinctive activation of the MAPKs in rVvhA-treated HT-29 cells. Interestingly, CN significantly restored the expression of Bax, Bcl-2, and cleaved caspase-3 as regulated by the phosphorylation of NF-κB. In mouse models of V. vulnificus infection, treatment with CN had a blocking effect that elevated the levels of TUNEL-positive DNA fragmentation and apoptosis-related proteins. These results indicate that CN is a functional agent that manipulates the V. vulnificus VvhA signaling pathway responsible for gastrointestinal cell death.
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Morte Celular/efeitos dos fármacos , Curcumina/farmacologia , Nanosferas/uso terapêutico , Vibrio vulnificus/metabolismo , Apoptose/efeitos dos fármacos , Proteínas de Bactérias/genética , Curcumina/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Humanos , NF-kappa B/metabolismo , Proteínas Recombinantes/metabolismo , Vibrio vulnificus/genéticaRESUMO
Cation-binding salen nickel catalysts were developed for the enantioselective alkynylation of trifluoromethyl ketones in high yield (up to 99 %) and high enantioselectivity (up to 97 % ee). The reaction proceeds with substoichiometric quantities of base (10-20â mol % KOt-Bu) and open to air. In the case of trifluoromethyl vinyl ketones, excellent chemo-selectivity was observed, generating 1,2-addition products exclusively over 1,4-addition products. UV-vis analysis revealed the pendant oligo-ether group of the catalyst strongly binds to the potassium cation (K+ ) with 1:1 binding stoichiometry (Ka =6.6×105 m-1 ).
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Cetonas/química , Níquel/química , Catálise , Estrutura Molecular , EstereoisomerismoRESUMO
The authors regret that incorrect western band of Bax (MDA-MB-231) in Fig. 6a (right panel) was mistakenly uploaded in the original publication. The correct Fig. 6a is shown below. This correction does not change the conclusions of this manuscript. The authors would like to apologize for any inconvenience caused.
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The genus Sapovirus belongs to the family Caliciviridae, and its members are common causative agents of severe acute gastroenteritis in both humans and animals. Some caliciviruses are known to use either terminal sialic acids or histo-blood group antigens as attachment factors and/or cell surface proteins, such as CD300lf, CD300ld, and junctional adhesion molecule 1 of tight junctions (TJs), as receptors. However, the roles of TJs and their proteins in sapovirus entry have not been examined. In this study, we found that porcine sapovirus (PSaV) significantly decreased transepithelial electrical resistance and increased paracellular permeability early in infection of LLC-PK cells, suggesting that PSaV dissociates TJs of cells. This led to the interaction between PSaV particles and occludin, which traveled in a complex into late endosomes via Rab5- and Rab7-dependent trafficking. Inhibition of occludin using small interfering RNA (siRNA), a specific antibody, or a dominant-negative mutant significantly blocked the entry of PSaV. Transient expression of occludin in nonpermissive Chinese hamster ovary (CHO) cells conferred susceptibility to PSaV, but only for a limited time. Although claudin-1, another TJ protein, neither directly interacted nor was internalized with PSaV particles, it facilitated PSaV entry and replication in the LLC-PK cells. We conclude that PSaV particles enter LLC-PK cells by binding to occludin as a coreceptor in PSaV-dissociated TJs. PSaV and occludin then form a complex that moves to late endosomes via Rab5- and Rab7-dependent trafficking. In addition, claudin-1 in the TJs opened by PSaV infection facilitates PSaV entry and infection as an entry factor.IMPORTANCE Sapoviruses (SaVs) cause severe acute gastroenteritis in humans and animals. Although they replicate in intestinal epithelial cells, which are tightly sealed by apical-junctional complexes, such as tight junctions (TJs), the mechanisms by which SaVs hijack TJs and their proteins for successful entry and infection remain largely unknown. Here, we demonstrate that porcine SaVs (PSaVs) induce early dissociation of TJs, allowing them to bind to the TJ protein occludin as a functional coreceptor. PSaVs then travel in a complex with occludin into late endosomes through Rab5- and Rab7-dependent trafficking. Claudin-1, another TJ protein, does not directly interact with PSaV but facilitates the entry of PSaV into cells as an entry factor. This work contributes to our understanding of the entry of SaV and other caliciviruses into cells and may aid in the development of efficient and affordable drugs to treat SaV infections.