RESUMEN
BACKGROUND: The LYP tyrosine phosphatase presents a SNP (1858C > T) that increases the risk of developing autoimmune diseases such as type I diabetes and arthritis. It remains unclear how this SNP affects LYP function and promotes the development of these diseases. The scarce information about LYP substrates is in part responsible for the poor understanding of LYP function. RESULTS: In this study, we identify in T lymphocytes several adaptor proteins as potential substrates targeted by LYP, including FYB, SLP-76, HS-1, Vav, SKAP1 and SKAP2. We also show that LYP co-localizes with SLP76 in microclusters, upon TCR engagement. CONCLUSIONS: These data indicate that LYP may modulate T cell activation by dephosphorylating several adaptor proteins, such as FYB, SLP-76, HS-1, Vav, SKAP1 and SKAP2 upon TCR engagement.
Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Fosfoproteínas , Proteína Asociada a la Molécula de Señalización de la Activación Linfocitaria , Linfocitos T , Humanos , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Células Jurkat , Activación de Linfocitos , Fosfoproteínas/metabolismo , Fosforilación , Proteínas Tirosina Fosfatasas/metabolismo , Receptores de Antígenos de Linfocitos T/metabolismo , Linfocitos T/metabolismo , Proteína Asociada a la Molécula de Señalización de la Activación Linfocitaria/genética , Proteína Asociada a la Molécula de Señalización de la Activación Linfocitaria/metabolismoRESUMEN
SARS-CoV-2 is the causative virus of COVID-19, which has been responsible for millions of deaths worldwide since its discovery. After its emergence, several variants have been identified that challenge the efficacy of the available vaccines. Previously, we generated and evaluated a vaccine based on a recombinant Bacillus Calmette-Guérin (rBCG) expressing the nucleoprotein (N) of SARS-CoV-2 (rBCG-N-SARS-CoV-2). This protein is a highly immunogenic antigen and well conserved among variants. Here, we tested the administration of this vaccine with recombinant N and viral Spike proteins (S), or Receptor Binding Domain (RBD-Omicron variant), plus a booster with the recombinant proteins only, as a novel and effective strategy to protect against SARS-CoV-2 variants. METHODS: BALB/c mice were immunized with rBCG-N-SARS-CoV-2 and recombinant SARS-CoV-2 proteins in Alum adjuvant, followed by a booster with recombinant proteins to assess the safety and virus-specific cellular and humoral immune responses against SARS-CoV-2 antigens. RESULTS: Immunization with rBCG-N-SARS-CoV-2 + recombinant proteins as a vaccine was safe and promoted the activation of CD4+ and CD8+ T cells that recognize SARS-CoV-2 N, S, and RBD antigens. These cells were able to secrete cytokines with an antiviral profile. This immunization strategy also induced robust titers of specific antibodies against N, S, and RBD and neutralizing antibodies of SARS-CoV-2. CONCLUSIONS: Co-administration of the rBCG-N-SARS-CoV-2 vaccine with recombinant SARS-CoV-2 proteins could be an effective alternative to control particular SARS-CoV-2 variants. Due to its safety and capacity to induce virus-specific immune responses, we believe the rBCG-N-SARS-CoV-2 + Proteins vaccine could be an attractive candidate to protect against this virus, especially in newborns.
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Anticuerpos Antivirales , Vacuna BCG , Vacunas contra la COVID-19 , COVID-19 , Ratones Endogámicos BALB C , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Animales , Ratones , SARS-CoV-2/inmunología , SARS-CoV-2/genética , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Glicoproteína de la Espiga del Coronavirus/genética , COVID-19/prevención & control , COVID-19/inmunología , Vacunas contra la COVID-19/inmunología , Vacunas contra la COVID-19/administración & dosificación , Vacuna BCG/inmunología , Vacuna BCG/administración & dosificación , Vacuna BCG/genética , Femenino , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/inmunología , Inmunización Secundaria , Vacunas Sintéticas/inmunología , Vacunas Sintéticas/administración & dosificación , Inmunidad Humoral , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/genética , Proteínas de la Nucleocápside de Coronavirus/inmunología , Proteínas de la Nucleocápside de Coronavirus/genética , Linfocitos T CD8-positivos/inmunología , Fosfoproteínas/inmunología , Fosfoproteínas/genética , Adyuvantes Inmunológicos/administración & dosificación , Inmunidad CelularRESUMEN
Atypical enteropathogenic Escherichia coli (aEPEC) is a significant cause of diarrhea in low- and middle-income countries. Certain aEPEC strains, including the Brazilian representative strain of serotype O51:H40 called aEPEC 1711-4, can use flagella to attach to, invade, and persist in T84 and Caco-2 intestinal cells. It can also translocate from the gut to extraintestinal sites in a rat model. Although various aspects of the virulence of this strain were studied and the requirement of a type III secretion system for the efficiency of the invasion process was demonstrated, the expression of the locus of enterocyte effacement (LEE) genes during the invasion and intracellular persistence remains unclear. To address this question, the expression of flagella and the different LEE operons was evaluated during kinetic experiments of the interaction of aEPEC 1711-4 with enterocytes in vitro. The genome of the strain was also sequenced. The results showed that flagella expression remained unchanged, but the expression of eae and escJ increased during the early interaction and invasion of aEPEC 1711-4 into Caco-2 cells, and there was no change 24 h post-infection during the persistence period. The number of actin accumulation foci formed on HeLa cells also increased during the 6-h analysis. No known gene related to the invasion process was identified in the genome of aEPEC 1711-4, which was shown to belong to the global EPEC lineage 10. These findings suggest that the LEE components and the intimate adherence promoted by intimin are necessary for the invasion and persistence of aEPEC 1711-4, but the detailed mechanism needs further study.IMPORTANCEAtypical enteropathogenic Escherichia coli (aEPEC) is a major cause of diarrhea, especially in low- and middle-income countries, like Brazil. However, due to the genome heterogeneity of each clonal group, it is difficult to comprehend the pathogenicity of this strain fully. Among aEPEC strains, 1711-4 can invade eukaryotic cells in vitro, cross the gut barrier, and reach extraintestinal sites in animal models. By studying how different known aEPEC virulence factors are expressed during the invasion process, we can gain insight into the commonalities of this phenotype among other aEPEC strains. This will help in developing preventive measures to control infections caused by invasive strains. No known virulence-encoding genes linked to the invasion process were found. Nevertheless, additional studies are still necessary to evaluate the role of other factors in this phenotype.
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Enterocitos , Escherichia coli Enteropatógena , Infecciones por Escherichia coli , Proteínas de Escherichia coli , Flagelos , Serogrupo , Escherichia coli Enteropatógena/genética , Escherichia coli Enteropatógena/patogenicidad , Escherichia coli Enteropatógena/metabolismo , Humanos , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Enterocitos/microbiología , Células CACO-2 , Infecciones por Escherichia coli/microbiología , Flagelos/genética , Flagelos/metabolismo , Virulencia/genética , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Regulación Bacteriana de la Expresión Génica , Adhesión Bacteriana/genética , Animales , Brasil , Factores de Virulencia/genética , Factores de Virulencia/metabolismo , Operón/genética , RatasRESUMEN
The nucleocapsid (N) protein of SARS-CoV-2 is a multifunctional protein involved in nucleocapsid assembly and various regulatory functions. It is the most abundant protein during viral infection. Its functionality is closely related to its structure, which comprises two globular domains, the N-terminal domain (NTD) and the C-terminal domain (CTD), flanked by intrinsically disordered regions. The linker between the NTD and CTD includes a Serine-Arginine rich (SR) region, which is crucial for the regulation of the N protein's function. Here, we report the near-complete assignment of the construct containing the NTD followed by the SR region (NTD-SR). Additionally, we describe the dynamic nature of the SR region and compare it with all other available chemical shift assignments reported for the SR region.
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Proteínas de la Nucleocápside de Coronavirus , Proteínas Intrínsecamente Desordenadas , Isótopos de Nitrógeno , Resonancia Magnética Nuclear Biomolecular , Fosfoproteínas , Dominios Proteicos , SARS-CoV-2 , Proteínas de la Nucleocápside de Coronavirus/química , SARS-CoV-2/química , Proteínas Intrínsecamente Desordenadas/química , Fosfoproteínas/química , Arginina/química , Isótopos de Carbono , Serina , Proteínas de la Nucleocápside/química , Secuencia de AminoácidosRESUMEN
Parasites have been associated with possible anticancer activity, including Trypanosoma cruzi, which has been linked to inhibiting the growth of solid tumors. To better understand this antitumor effect, we investigated the association of anti-T. cruzi antibodies with B cells of the acute lymphoblastic leukemia (ALL) SUPB15 cell line. The antibodies were generated in rabbits. IgGs were purified by affinity chromatography. Two procedures (flow cytometry (CF) and Western blot(WB)) were employed to recognize anti-T. cruzi antibodies on SUPB15 cells. We also used CF to determine whether the anti-T. cruzi antibodies could suppress SUPB15 cells. The anti-T. cruzi antibodies recognized 35.5% of the surface antigens of SUPB15. The complement-dependent cytotoxicity (CDC) results demonstrate the cross-suppression of anti-T. cruzi antibodies on up to 8.4% of SUPB15 cells. For the WB analysis, a band at 100 kDa with high intensity was sequenced using mass spectrometry, identifying the protein as nucleolin. This protein may play a role in the antitumor effect on T. cruzi. The anti-T. cruzi antibodies represent promising polyclonal antibodies that have the effect of tumor-suppressive cross-linking on cancer cells, which should be further investigated.
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Anticuerpos Antiprotozoarios , Leucemia-Linfoma Linfoblástico de Células Precursoras , Trypanosoma cruzi , Trypanosoma cruzi/inmunología , Leucemia-Linfoma Linfoblástico de Células Precursoras/inmunología , Humanos , Línea Celular Tumoral , Animales , Conejos , Anticuerpos Antiprotozoarios/inmunología , Proteínas de Unión al ARN/inmunología , Proteínas de Unión al ARN/metabolismo , Nucleolina , Fosfoproteínas/inmunología , Fosfoproteínas/metabolismoRESUMEN
Numerous commercial tests for the serological diagnosis of COVID-19 have been produced in recent years. However, it is important to note that these tests exhibit significant variability in their sensitivity, specificity, and accuracy of results. Therefore, the objective of this study was to utilize bioinformatics tools to map SARS-CoV-2 peptides, with the goal of developing a new serological diagnostic test for COVID-19. Two peptides from the S protein and one from the N protein were selected and characterized in silico, chemically synthesized, and used as a serological diagnostic tool to detect IgM, IgG, and IgA anti-SARS-CoV-2 antibodies through the ELISA technique, confirmed as positive and negative samples by RT-qPCR or serology by ELISA. The results showed a sensitivity, specificity, Positive Predictive Value and Negative Predictive Value of 100% (p < 00001, 95% CI) for the proposed test. Although preliminary, this study brings proof-of-concept results that are consistent with the high-performance rates of the ELISA test when compared to other well-established methods for diagnosing COVID-19.
Asunto(s)
Anticuerpos Antivirales , Prueba Serológica para COVID-19 , COVID-19 , Proteínas de la Nucleocápside de Coronavirus , Ensayo de Inmunoadsorción Enzimática , SARS-CoV-2 , Sensibilidad y Especificidad , Glicoproteína de la Espiga del Coronavirus , Humanos , COVID-19/diagnóstico , SARS-CoV-2/inmunología , SARS-CoV-2/aislamiento & purificación , SARS-CoV-2/genética , Anticuerpos Antivirales/sangre , Glicoproteína de la Espiga del Coronavirus/inmunología , Prueba Serológica para COVID-19/métodos , Ensayo de Inmunoadsorción Enzimática/métodos , Proteínas de la Nucleocápside de Coronavirus/inmunología , Fosfoproteínas/inmunología , Inmunoglobulina M/sangre , Péptidos/inmunología , Péptidos/química , Inmunoglobulina G/sangre , Biología Computacional/métodosRESUMEN
BACKGROUND: Natural infection and vaccination against SARS-CoV-2 is associated with the development of immunity against the structural proteins of the virus. Specifically, the two most immunogenic are the S (spike) and N (nucleocapsid) proteins. Seroprevalence studies performed in university students provide information to estimate the number of infected patients (symptomatic or asymptomatic) and generate knowledge about the viral spread, vaccine efficacy, and epidemiological control. Which, the aim of this study was to evaluate IgG antibodies against the S and N proteins of SARS-CoV-2 at university students from Southern Mexico. METHODS: A total of 1418 serum samples were collected from eighteen work centers of the Autonomous University of Guerrero. Antibodies were detected by Indirect ELISA using as antigen peptides derived from the S and N proteins. RESULTS: We reported a total seroprevalence of 39.9% anti-S/N (positive to both antigens), 14.1% anti-S and 0.5% anti-N. The highest seroprevalence was reported in the work centers from Costa Grande, Acapulco and Centro. Seroprevalence was associated with age, COVID-19, contact with infected patients, and vaccination. CONCLUSION: University students could play an essential role in disseminating SARS-CoV-2. We reported a seroprevalence of 54.5% against the S and N proteins, which could be due to the high population rate and cultural resistance to safety measures against COVID-19 in the different regions of the state.
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Anticuerpos Antivirales , COVID-19 , Proteínas de la Nucleocápside de Coronavirus , Inmunoglobulina G , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Estudiantes , Humanos , México/epidemiología , Masculino , Femenino , Estudios Transversales , Glicoproteína de la Espiga del Coronavirus/inmunología , Inmunoglobulina G/sangre , COVID-19/epidemiología , COVID-19/inmunología , Adulto Joven , Anticuerpos Antivirales/sangre , SARS-CoV-2/inmunología , Estudios Seroepidemiológicos , Adulto , Universidades , Proteínas de la Nucleocápside de Coronavirus/inmunología , Adolescente , Fosfoproteínas/inmunologíaRESUMEN
This paper reports a rapid and sensitive sensor for the detection and quantification of the COVID-19 N-protein (N-PROT) via an electrochemical mechanism. Single-frequency electrochemical impedance spectroscopy was used as a transduction method for real-time measurement of the N-PROT in an immunosensor system based on gold-conjugate-modified carbon screen-printed electrodes (Cov-Ag-SPE). The system presents high selectivity attained through an optimal stimulation signal composed of a 0.0 V DC potential and 10 mV RMS-1 AC signal at 100 Hz over 300 s. The Cov-Ag-SPE showed a log response toward N-PROT detection at concentrations from 1.0 ng mL-1 to 10.0 µg mL-1, with a 0.977 correlation coefficient for the phase (θ) variation. An ML-based approach could be created using some aspects observed from the positive and negative samples; hence, it was possible to classify 252 samples, reaching 83.0, 96.2 and 91.3% sensitivity, specificity, and accuracy, respectively, with confidence intervals (CI) ranging from 73.0 to 100.0%. Because impedance spectroscopy measurements can be performed with low-cost portable instruments, the immunosensor proposed here can be applied in point-of-care diagnostics for mass testing, even in places with limited resources, as an alternative to the common diagnostics methods.
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Técnicas Biosensibles , COVID-19 , Espectroscopía Dieléctrica , Oro , SARS-CoV-2 , COVID-19/diagnóstico , COVID-19/virología , Técnicas Biosensibles/métodos , Técnicas Biosensibles/instrumentación , Humanos , SARS-CoV-2/aislamiento & purificación , SARS-CoV-2/inmunología , Espectroscopía Dieléctrica/instrumentación , Espectroscopía Dieléctrica/métodos , Oro/química , Electrodos , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Inmunoensayo/métodos , Inmunoensayo/instrumentación , Proteínas de la Nucleocápside de Coronavirus/inmunología , Proteínas de la Nucleocápside de Coronavirus/análisis , Carbono/química , Fosfoproteínas/análisisRESUMEN
Vaccination is one of the most effective prophylactic public health interventions for the prevention of infectious diseases such as coronavirus disease (COVID-19). Considering the ongoing need for new COVID-19 vaccines, it is crucial to modify our approach and incorporate more conserved regions of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to effectively address emerging viral variants. The nucleocapsid protein is a structural protein of SARS-CoV-2 that is involved in replication and immune responses. Furthermore, this protein offers significant advantages owing to the minimal accumulation of mutations over time and the inclusion of key T-cell epitopes critical for SARS-CoV-2 immunity. A novel strategy that may be suitable for the new generation of vaccines against COVID-19 is to use a combination of antigens, including the spike and nucleocapsid proteins, to elicit robust humoral and potent cellular immune responses, along with long-lasting immunity. The strategic use of multiple antigens aims to enhance vaccine efficacy and broaden protection against viruses, including their variants. The immune response against the nucleocapsid protein from other coronavirus is long-lasting, and it can persist up to 11 years post-infection. Thus, the incorporation of nucleocapsids (N) into vaccine design adds an important dimension to vaccination efforts and holds promise for bolstering the ability to combat COVID-19 effectively. In this review, we summarize the preclinical studies that evaluated the use of the nucleocapsid protein as antigen. This study discusses the use of nucleocapsid alone and its combination with spike protein or other proteins of SARS-CoV-2.
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Vacunas contra la COVID-19 , COVID-19 , Proteínas de la Nucleocápside de Coronavirus , SARS-CoV-2 , Humanos , Vacunas contra la COVID-19/inmunología , SARS-CoV-2/inmunología , COVID-19/prevención & control , COVID-19/inmunología , Proteínas de la Nucleocápside de Coronavirus/inmunología , Proteínas de la Nucleocápside de Coronavirus/genética , Inmunogenicidad Vacunal , Animales , Fosfoproteínas/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Glicoproteína de la Espiga del Coronavirus/genética , Epítopos de Linfocito T/inmunología , Anticuerpos Antivirales/inmunología , Proteínas de la Nucleocápside/inmunologíaRESUMEN
BACKGROUND: NSCLC is one of the most common causes of death. The hypoxia microenvironment contributes to cancer progression. The purpose was to explore the effects and mechanism of melittin on NSCLC cells in the hypoxic microenvironment. METHODS: NSCLC cell lines (A549 and H1299) were cultured in normoxia or hypoxia conditions with or without melittin treatment. The viability of the cells was detected via MTT assay and the proliferation ability was evaluated by EdU assay. QRT-PCR was performed to evaluate GLUT1, LDHA, HK2, VEGF and LATS2 mRNA levels. Glucose transport was assessed by the 2-NBDG uptake assay. The angiogenesis was determined by the tubule formation assay. The protein expressions of GLUT1, LDHA, HK2, VEGF, LATS2, YAP, p-YAP and HIF-1α were detected via western blotting assay. The tumor formation assay was conducted to examine the roles of melittin and LATS2 in vivo. RESULTS: Melittin inhibited hypoxia-induced cell viability, proliferation, glycolysis and angiogenesis as well as suppressed YAP binding to HIF-1α in NSCLC. Melittin inactivated the YAP/HIF-1α pathway via up-regulation of LATS2, ultimately inhibiting cancer progression of NSCLC. Moreover, melittin suppressed tumor growth via up-regulation of LATS2 in vivo. CONCLUSION: Melittin inactivated the YAP/HIF-1α pathway via up-regulation of LATS2 to contribute to the development of NSCLC. Therefore, melittin is expected to become a potential prognostic drug for the therapy of NSCLC.
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Carcinoma de Pulmón de Células no Pequeñas , Proliferación Celular , Glucólisis , Subunidad alfa del Factor 1 Inducible por Hipoxia , Neoplasias Pulmonares , Meliteno , Neovascularización Patológica , Proteínas Serina-Treonina Quinasas , Proteínas Supresoras de Tumor , Regulación hacia Arriba , Proteínas Señalizadoras YAP , Humanos , Proteínas Serina-Treonina Quinasas/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/irrigación sanguínea , Carcinoma de Pulmón de Células no Pequeñas/patología , Proliferación Celular/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacos , Glucólisis/efectos de los fármacos , Proteínas Supresoras de Tumor/metabolismo , Neovascularización Patológica/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Proteínas Señalizadoras YAP/metabolismo , Meliteno/farmacología , Meliteno/uso terapéutico , Línea Celular Tumoral , Factores de Transcripción/metabolismo , Animales , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Transducción de Señal/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Fosfoproteínas/metabolismo , AngiogénesisRESUMEN
This study focuses on the development and initial assessment of an indirect IgG enzyme-linked immunosorbent assay (ELISA) specifically designed to detect of anti-SARS-CoV-2 antibodies. The unique aspect of this ELISA method lies in its utilization of a recombinant nucleocapsid (N) antigen, produced through baculovirus expression in insect cells. Our analysis involved 292 RT-qPCR confirmed positive serum samples and 54 pre-pandemic healthy controls. The process encompassed cloning, expression, and purification of the SARS-CoV-2 N gene in insect cells, with the resulted purified protein employed in our ELISA tests. Statistical analysis yielded an Area Under the Curve of 0.979, and the optimized cut-off exhibited 92 % sensitivity and 94 % specificity. These results highlight the ELISA's potential for robust and reliable serological detection of SARS-CoV-2 antibodies. Further assessments, including a larger panel size, reproducibility tests, and application in diverse populations, could enhance its utility as a valuable biotechnological solution for diseases surveillance.
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Anticuerpos Antivirales , Baculoviridae , COVID-19 , Ensayo de Inmunoadsorción Enzimática , Proteínas Recombinantes , SARS-CoV-2 , Ensayo de Inmunoadsorción Enzimática/métodos , Humanos , SARS-CoV-2/inmunología , SARS-CoV-2/genética , Baculoviridae/genética , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/genética , COVID-19/diagnóstico , COVID-19/sangre , COVID-19/inmunología , Animales , Proteínas de la Nucleocápside de Coronavirus/inmunología , Proteínas de la Nucleocápside de Coronavirus/genética , Prueba Serológica para COVID-19/métodos , Células Sf9 , Antígenos Virales/inmunología , Antígenos Virales/genética , Proteínas de la Nucleocápside/inmunología , Proteínas de la Nucleocápside/genética , Sensibilidad y Especificidad , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Fosfoproteínas/inmunología , Fosfoproteínas/genéticaRESUMEN
The immune response to SARS-CoV-2 has been extensively studied following the pandemic outbreak in 2020; however, the presence of specific T cells against SARS-CoV-2 before vaccination has not been evaluated in Mexico. In this study, we estimated the frequency of T CD4+ and T CD8+ cells that exhibit a specific response to S (spike) and N (nucleocapsid) proteins in a Mexican population. We collected 78 peripheral blood samples from unvaccinated subjects, and the presence of antibodies against spike (RBD) and N protein was determined. Peripheral blood mononuclear cells were isolated and stimulated with a pool of S or N protein peptides (Wuhan-Hu-1 strain). IL-1ß, IL-4, IL-6, IL-10, IL-2, IL-8, TNF-α, IFN-γ, and GM-CSF levels were quantified in the supernatant of the activated cells, and the cells were stained to assess the activation and memory phenotypes. Differential activation frequency dependent on serological status was observed in CD4+ cells but not in CD8+ cells. The predominantly activated population was the central memory T CD4+ cells. Only 10% of the population exhibited the same phenotype with respect to the response to nucleocapsid peptides. The cytokine profile differed between the S and N responses. S peptides induced a more proinflammatory response compared with the N peptides. In conclusion, in a Mexican cohort before vaccination, there was a significant response to the S and N SARS-CoV-2 proteins resulting from previous infections with seasonal coronaviruses or previous undetected exposure to SARS-CoV-2.
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Linfocitos T CD4-Positivos , Linfocitos T CD8-positivos , COVID-19 , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Vacunación , Humanos , México/epidemiología , SARS-CoV-2/inmunología , COVID-19/inmunología , COVID-19/epidemiología , COVID-19/prevención & control , Femenino , Masculino , Adulto , Linfocitos T CD8-positivos/inmunología , Persona de Mediana Edad , Linfocitos T CD4-Positivos/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Citocinas/metabolismo , Vacunas contra la COVID-19/inmunología , Proteínas de la Nucleocápside de Coronavirus/inmunología , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Adulto Joven , Fosfoproteínas/inmunología , Anciano , Activación de Linfocitos/inmunologíaRESUMEN
The Hippo pathway, a signaling cascade involved in the regulation of organ size and several other processes, acts as a conduit between extracellular matrix (ECM) cues and cellular responses. We asked whether the basement membrane (BM), a specialized ECM component known to induce quiescence and differentiation in mammary epithelial cells, would regulate the localization, activity, and interactome of YAP, a Hippo pathway effector. To address this question, we used a broad range of experimental approaches, including 2D and 3D cultures of both mouse and human mammary epithelial cells, as well as the developing mouse mammary gland. In contrast to malignant cells, nontumoral cells cultured with a reconstituted BM (rBM) displayed higher concentrations of YAP in the cytoplasm. Incidentally, when in the nucleus of rBM-treated cells, YAP resided preferentially at the nuclear periphery. In agreement with our cell culture experiments, YAP exhibited cytoplasmic predominance in ductal cells of developing mammary epithelia, where a denser BM is found. Conversely, terminal end bud (TEB) cells with a thinner BM displayed higher nucleus-to-cytoplasm ratios of YAP. Bioinformatic analysis revealed that genes regulated by YAP were overrepresented in the transcriptomes of microdissected TEBs. Consistently, mouse epithelial cells exposed to the rBM expressed lower levels of YAP-regulated genes, although the protein level of YAP and Hippo components were slightly altered by the treatment. Mass spectrometry analysis identified a differential set of proteins interacting with YAP in cytoplasmic fractions of mouse epithelial cells in the absence or presence of rBM. In untreated cells, YAP interactants were enriched in processes related to ubiquitin-mediated proteolysis, whereas in cells exposed to rBM YAP interactants were mainly key proteins related to amino acid, amino sugar, and carbohydrate metabolism. Collectively, we unraveled that the BM induces YAP translocation or retention in the cytoplasm of nontumoral epithelial cells and that in the cytoplasm YAP seems to undertake novel functions in metabolic pathways.
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Proteínas Adaptadoras Transductoras de Señales , Membrana Basal , Citoplasma , Células Epiteliales , Factores de Transcripción , Proteínas Señalizadoras YAP , Animales , Humanos , Ratones , Células Epiteliales/metabolismo , Proteínas Señalizadoras YAP/metabolismo , Femenino , Citoplasma/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Membrana Basal/metabolismo , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Glándulas Mamarias Animales/metabolismo , Glándulas Mamarias Animales/citología , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Fosfoproteínas/metabolismo , Fosfoproteínas/genética , Glándulas Mamarias Humanas/metabolismo , Glándulas Mamarias Humanas/citología , Núcleo Celular/metabolismo , Transducción de SeñalRESUMEN
TREX1 acts in the initial prevention of an autoimmune response, but it may contribute to the permissiveness of retrovirus infections. This study investigated the association between the levels of TREX1 gene expression with the polymorphisms TREX1 rs3135941 (T/C) and TREX1 rs3135945 (G/A), and the presence of antinuclear antibodies (ANA) in antiretroviral therapy (ART)-naïve individuals and after 1 year of treatment. Blood samples from 119 individuals with HIV-1 were subjected to genotyping of polymorphisms and quantification of TREX1 gene expression and HIV-1 viral load by qPCR. The concentration of IFN-α and the number of CD4+/CD8+ T lymphocytes were determined by ELISA and flow cytometry, respectively; ANA was investigated by immunofluorescence. A control group of 167 seronegative individuals was used for the comparison of genotypic frequencies. The frequency of the polymorphisms were not associated with HIV infection or with variations in the expression of TREX1 and IFN-α (p > 0.05). ART-naïve individuals exhibited higher TREX1 expression and lower IFN-α expression. After 1 year of ART, TREX1 levels were reduced, while IFN-α and CD4+ T lymphocytes were elevated (p < 0.05). Some individuals on ART presented ANA. These results suggest that ART-mediated restoration of immune competence is associated with a reduction in TREX1 expression, which may induce the development of ANA, regardless of the polymorphism investigated.
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Exodesoxirribonucleasas , Infecciones por VIH , VIH-1 , Reconstitución Inmune , Fosfoproteínas , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Anticuerpos Antinucleares/sangre , Linfocitos T CD4-Positivos/inmunología , Exodesoxirribonucleasas/genética , Exodesoxirribonucleasas/metabolismo , Genotipo , Infecciones por VIH/inmunología , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/genética , Infecciones por VIH/virología , VIH-1/inmunología , Reconstitución Inmune/genética , Reconstitución Inmune/inmunología , Interferón-alfa/sangre , Interferón-alfa/metabolismo , Fosfoproteínas/genética , Polimorfismo de Nucleótido Simple , Carga Viral , Antirretrovirales/efectos adversos , Antirretrovirales/uso terapéuticoRESUMEN
This work analyzes the role of the tight junction (TJ) protein ZO-2 on mechanosensation. We found that the lack of ZO-2 reduced apical membrane rigidity measured with atomic force microscopy, inhibited the association of γ-actin and JAM-A to the cell border, and instead facilitated p114RhoGEF and afadin accumulation at the junction, leading to an enhanced mechanical tension at the TJ measured by FRET, with a ZO-1 tension probe, and increased tricellular TJ tension. Simultaneously, adherens junction tension measured with an E-cadherin probe was unaltered. The stability of JAM-A and ZO-2 binding was assessed by a collaborative in silico study. The absence of ZO-2 also impacted the cell response to the substrate, as monolayers plated in 20 kPa hydrogels developed holes not seen in parental cultures and displayed a retarded elongation and formation of cell aggregates. The absence of ZO-2 was sufficient to induce YAP and Snail nuclear accumulation in cells cultured over glass, but when ZO-2 KD cells were plated in nanostructured ridge arrays, they displayed an increased abundance of nuclear Snail and conspicuous internalization of claudin-4. These results indicate that the absence of ZO-2 also impairs the response of cells to substrate stiffness and exacerbates transformation triggered by substrate topography.
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Actinas , Uniones Estrechas , Actinas/metabolismo , Uniones Estrechas/metabolismo , Proteína de la Zonula Occludens-1/metabolismo , Fosfoproteínas/metabolismoRESUMEN
Treacle ribosome biogenesis factor 1 (TCOF1) is responsible for about 80% of mandibular dysostosis (MD) cases. We have formerly identified a correlation between TCOF1 and CNBP (CCHC-type zinc finger nucleic acid binding protein) expression in human mesenchymal cells. Given the established role of CNBP in gene regulation during rostral development, we explored the potential for CNBP to modulate TCOF1 transcription. Computational analysis for CNBP binding sites (CNBP-BSs) in the TCOF1 promoter revealed several putative binding sites, two of which (Hs791 and Hs2160) overlap with putative G-quadruplex (G4) sequences (PQSs). We validated the folding of these PQSs measuring circular dichroism and fluorescence of appropriate synthetic oligonucleotides. In vitro studies confirmed binding of purified CNBP to the target PQSs (both folded as G4 and unfolded) with Kd values in the nM range. ChIP assays conducted in HeLa cells chromatin detected the CNBP binding to TCOF1 promoter. Transient transfections of HEK293 cells revealed that Hs2160 cloned upstream SV40 promoter increased transcription of downstream firefly luciferase reporter gene. We also detected a CNBP-BS and PQS (Dr2393) in the zebrafish TCOF1 orthologue promoter (nolc1). Disrupting this G4 in zebrafish embryos by microinjecting DNA antisense oligonucleotides complementary to Dr2393 reduced the transcription of nolc1 and recapitulated the craniofacial anomalies characteristic of Treacher Collins Syndrome. Both cnbp overexpression and Morpholino-mediated knockdown in zebrafish induced nolc1 transcription. These results suggest that CNBP modulates the transcriptional expression of TCOF1 through a mechanism involving G-quadruplex folding/unfolding, and that this regulation is active in vertebrates as distantly related as bony fish and humans. These findings may have implications for understanding and treating MD.
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G-Cuádruplex , Disostosis Mandibulofacial , Animales , Humanos , ADN/metabolismo , Células HEK293 , Células HeLa , Disostosis Mandibulofacial/genética , Disostosis Mandibulofacial/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fosfoproteínas/metabolismo , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Factores de Transcripción/metabolismo , Pez Cebra/genética , Pez Cebra/metabolismoRESUMEN
For many years, research in the field of steroid synthesis has aimed to understand the regulation of the rate-limiting step of steroid synthesis, i.e. the transport of cholesterol from the outer to the inner mitochondrial membrane, and identify the protein involved in the conversion of cholesterol into pregnenolone. The extraordinary work by B Clark, J Wells, S R King, and D M Stocco eventually identified this protein and named it steroidogenic acute regulatory protein (StAR). The group's finding was also one of the milestones in understanding the mechanism of nonvesicular lipid transport between organelles. A notable feature of StAR is its high degree of phosphorylation. In fact, StAR phosphorylation in the acute phase is required for full steroid biosynthesis. As a contribution to this subject, our work has led to the characterization of StAR as a substrate of kinases and phosphatases and as an integral part of a mitochondrion-associated multiprotein complex, essential for StAR function and cholesterol binding and mitochondrial transport to yield maximum steroid production. Results allow us to postulate the existence of a specific cellular microenvironment where StAR protein synthesis and activation, along with steroid synthesis and secretion, are performed in a compartmentalized manner, at the site of hormone receptor stimulation, and involving the compartmentalized formation of the steroid molecule-synthesizing complex.
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Fosfoproteínas , Esteroides , Fosfoproteínas/metabolismo , Colesterol/metabolismo , Microambiente CelularRESUMEN
Acquired enamel pellicle plays an important role in the pathogenesis of early childhood caries (ECC), working as a protective interface between the tooth and the oral cavity. The aim of this cross-sectional in vivo proteomic study was to compare the acquired enamel pellicle protein profile of 3-5-year-old children with ECC (n = 10) and caries-free children (n = 10). Acquired enamel pellicle samples were collected and processed for proteomic analysis (nLC-ESI-MS/MS). In total, 241 proteins were identified. Basic salivary proline-rich protein 1 and 2, Cystatin-B, and SA were found only in the caries free group. When comparing caries free and ECC groups, lower protein levels were found in the caries free group for hemoglobin subunit beta, delta, epsilon, gamma-2, globin domain-containing protein and gamma-1, neutrophil defensin 3, serum albumin, protein S100-A8, and S100-A9. The proteins histatin-1, statherin, salivary acidic proline-rich phosphoprotein ½, proline-rich protein 4, submaxillary gland androgen-regulated protein 3B, alpha-amylase 1 and 2B were found at higher levels in the caries free group. The exclusive and the proteins found at higher levels in the caries free group might have protective functions that play a role in the prevention of caries, besides providing important insights to be evaluated in future studies for the possible development of new therapeutic strategies for ECC.
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Caries Dental , Espectrometría de Masas en Tándem , Preescolar , Humanos , Película Dental/metabolismo , Proteómica , Estudios Transversales , Fosfoproteínas/metabolismo , Prolina/metabolismo , Proteínas y Péptidos Salivales/metabolismo , SalivaRESUMEN
Inflammasomes are multiprotein complexes that play a role in the processing of proinflammatory cytokines such as interleukin 1 beta (IL-1ß). The secretion of IL-1ß in bovine macrophages infected with the bovine viral diarrhea virus (BVDV) cytopathic strain NADL (NADLcp-BVDV) is caspase 1-dependent. In the present study, we found that in macrophages infected with NADL, the NLRP3 inflammasome participated in the maturation of IL-1ß as the level decreased from 4629.3 pg/mL to 897.0 pg/mL after treatment with cytokine release inhibitory drug 3 (CRID3). Furthermore, NLRP3 activation has implications regarding viral replication, as there was a decrease in the viral titer until 1 log of a supernatant of macrophages that were inhibited with CRID3 remained. In the case of the non-cytopathic BVDV strain NY-1 (NY-1 ncpBVDV), IL-1ß secretion is not affected by NLRP3, but could be related to the IFI16 inflammasome; we found a colocalization of IFI16 with ASC using confocal microscopy in infected macrophages with the NY-1 ncp-BVDV biotype. To relate IFI16 activation to IL-1ß release, we used ODN TTAGGG (A151), a competitive inhibitor of IFI16; the results show a decrease in its level from 248 pg/mL to 128.3 pg/mL. Additionally, we evaluated the caspase 1 activation downstream of IFI16 and found a decrease in the IL-1ß from 252.9 pg/mL to 63.5 pg/mL when caspase 1 was inhibited with Y-VAD. Our results provide an improved understanding of the mechanisms involved in the viral replication, inflammation and pathogenesis of bovine viral diarrhea.
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Virus de la Diarrea Viral Bovina Tipo 1 , Virus de la Diarrea Viral Bovina , Caspasa 1 , Citocinas , Diarrea , Inflamasomas , Interleucina-1beta , Macrófagos , Proteína con Dominio Pirina 3 de la Familia NLR , Proteínas Nucleares , Fosfoproteínas , Replicación Viral , Animales , BovinosRESUMEN
OBJECTIVE: Evaluate the association of genetic variants of the interferon gamma inducible protein 16 (IFI16) and absent in melanoma 2 (AIM2) genes with periodontitis. METHODS: The study involved 117 individuals with periodontitis and 389 without periodontitis, all Brazilians, miscegenated. Individuals with periodontitis presented at least 4 teeth with ≥ 1 site with probing depth ≥ 4 mm; clinical attachment level ≥ 3 mm on the same site and bleeding upon stimulus. Genotyping was performed using the Infinium Multi-Ethnic AMR/AFR-8 Bead Chip focused on Hispanic and African American populations with approximately 2 million markers of the human genome. Multivariate logistic regression was performed to identify associations in additive, dominant and recessive models adjusted for covariates age, obesity, mouth breathing, flossing, asthma, and ancestry. RESULTS: In IFI16, the rs75985579-A is positively associated with periodontitis in the additive (Odds Ratio adjusted (ORadjusted) 2.65, 95% confidence interval (CI):1.25-5.60, p value: 0.007) and dominant models (ORadjusted 2.56, 95%CI:1.13-5.81, p value: 0.017). In AIM2, the rs76457189-G, is associated negatively with periodontitis in two genetic models evaluated, additive (ORadjusted 0.21, 95%CI:0.05-0.94, p value: 0.022) and dominant (ORadjusted 0.21, 95%CI:0.05-0.94, p value: 0.022). CONCLUSIONS: These results have shown that variants in the IFI16 and AIM2 genes are associated with periodontitis. Individuals with at least one A (adenine) allele of the rs75985579 (IFI16) are more than twice as likely to have periodontitis, while individuals with the G (guanine) allele of rs76457189 (AIM2) are less likely to be diagnosed with periodontitis, providing a negative association with periodontitis.