Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 63
Filtrar
1.
Ann Hematol ; 103(4): 1167-1179, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38386032

RESUMO

Ischemic stroke (IS) is one of the most impairing complications of sickle cell anemia (SCA), responsible for 20% of mortality in patients. Rheological alterations, adhesive properties of sickle reticulocytes, leukocyte adhesion, inflammation and endothelial dysfunction are related to the vasculopathy observed prior to ischemic events. The role of the vascular endothelium in this complex cascade of mechanisms is emphasized, as well as in the process of ischemia-induced repair and neovascularization. The aim of the present study was to perform a comparative transcriptomic analysis of endothelial colony-forming cells (ECFCs) from SCA patients with and without IS. Next, to gain further insights of the biological relevance of differentially expressed genes (DEGs), functional enrichment analysis, protein-protein interaction network (PPI) construction and in silico prediction of regulatory factors were performed. Among the 2469 DEGs, genes related to cell proliferation (AKT1, E2F1, CDCA5, EGFL7), migration (AKT1, HRAS), angiogenesis (AKT1, EGFL7) and defense response pathways (HRAS, IRF3, TGFB1), important endothelial cell molecular mechanisms in post ischemia repair were identified. Despite the severity of IS in SCA, widely accepted molecular targets are still lacking, especially related to stroke outcome. The comparative analysis of the gene expression profile of ECFCs from IS patients versus controls seems to indicate that there is a persistent angiogenic process even after a long time this complication has occurred. Thus, this is an original study which may lead to new insights into the molecular basis of SCA stroke and contribute to a better understanding of the role of endothelial cells in stroke recovery.


Assuntos
Anemia Falciforme , Acidente Vascular Cerebral , Humanos , Células Endoteliais/metabolismo , Transcriptoma , Acidente Vascular Cerebral/genética , Acidente Vascular Cerebral/complicações , Anemia Falciforme/complicações , Isquemia , Perfilação da Expressão Gênica , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Família de Proteínas EGF/genética , Família de Proteínas EGF/metabolismo
2.
Nanomedicine (Lond) ; 18(18): 1175-1194, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37712604

RESUMO

Aim: To develop, characterize and evaluate an oil/water nanoemulsion with squalene (CTVad1) to be approved as an adjuvant for the SpiN COVID-19 vaccine clinical trials. Materials & methods: Critical process parameters (CPPs) of CTVad1 were standardized to meet the critical quality attributes (CQAs) of an adjuvant for human use. CTVad1 and the SpiN-CTVad1 vaccine were submitted to physicochemical, stability, in vitro and in vivo studies. Results & conclusion: All CQAs were met in the CTVad1 production process. SpiN- CTVad1 met CQAs and induced high levels of antibodies and specific cellular responses in in vivo studies. These results represented a critical step in the process developed to meet regulatory requirements for the SpiN COVID-19 vaccine clinical trial.


Assuntos
COVID-19 , Vacinas , Humanos , Vacinas contra COVID-19/uso terapêutico , Emulsões/química , COVID-19/prevenção & controle , Adjuvantes Imunológicos/uso terapêutico , Adjuvantes Imunológicos/química , Vacinas/química
4.
NPJ Vaccines ; 8(1): 81, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37258518

RESUMO

Immunization with the Amastigote Surface Protein-2 (ASP-2) and Trans-sialidase (TS) antigens either in the form of recombinant protein, encoded in plasmids or human adenovirus 5 (hAd5) confers robust protection against various lineages of Trypanosoma cruzi. Herein we generated a chimeric protein containing the most immunogenic regions for T and B cells from TS and ASP-2 (TRASP) and evaluated its immunogenicity in comparison with our standard protocol of heterologous prime-boost using plasmids and hAd5. Mice immunized with TRASP protein associated to Poly-ICLC (Hiltonol) were highly resistant to challenge with T. cruzi, showing a large decrease in tissue parasitism, parasitemia and no lethality. This protection lasted for at least 3 months after the last boost of immunization, being equivalent to the protection induced by DNA/hAd5 protocol. TRASP induced high levels of T. cruzi-specific antibodies and IFNγ-producing T cells and protection was primarily mediated by CD8+ T cells and IFN-γ. We also evaluated the toxicity, immunogenicity, and efficacy of TRASP and DNA/hAd5 formulations in dogs. Mild collateral effects were detected at the site of vaccine inoculation. While the chimeric protein associated with Poly-ICLC induced high levels of antibodies and CD4+ T cell responses, the DNA/hAd5 induced no antibodies, but a strong CD8+ T cell response. Immunization with either vaccine protected dogs against challenge with T. cruzi. Despite the similar efficacy, we conclude that moving ahead with TRASP together with Hiltonol is advantageous over the DNA/hAd5 vaccine due to pre-existing immunity to the adenovirus vector, as well as the cost-benefit for development and large-scale production.

5.
Vaccine ; 41(28): 4170-4182, 2023 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-37236818

RESUMO

Streptococcus pneumoniae is a common agent of important human diseases such as otitis media, pneumonia, meningitis and sepsis. Current available vaccines that target capsular polysaccharides induce protection against invasive disease and nasopharyngeal colonization in children, yet their efficacy is limited to the serotypes included in the formulations. The virulence factor Pneumococcal Surface Protein A (PspA) interacts with host immune system and helps the bacteria to evade phagocytosis. Due to its essential role in virulence, PspA is an important vaccine candidate. Here we have tested a delivery system based on the adenylate cyclase toxin of Bordetella pertussis (CyaA) to induce immune responses against PspA in mice. CyaA was engineered to express fragments of the N-terminal region of PspAs from clades 2 and 4 (A2 and A4) and the resulting proteins were used in immunization experiments in mice. The recombinant CyaA-A2 and CyaA-A4 proteins were able to induce high levels of anti-PspA antibodies that reacted with pneumococcal strains expressing either PspA2 or PspA4. Moreover, reactivity of the antibodies against pneumococcal strains that express PspAs from clades 3 and 5 (PspA3 and PspA5) was also observed. A formulation containing CyaA-A2 and CyaA-A4 was able to protect mice against invasive pneumococcal challenges with isolates that express PspA2, PspA4 or PspA5. Moreover, a CyaA-A2-A4 fusion protein induced antibodies at similar levels and with similar reactivity as the formulation containing both proteins, and protected mice against the invasive challenge. Our results indicate that CyaA-PspA proteins are good candidates to induce broad protection against pneumococcal isolates.


Assuntos
Infecções Pneumocócicas , Streptococcus pneumoniae , Criança , Animais , Camundongos , Humanos , Streptococcus pneumoniae/genética , Bordetella pertussis/genética , Adenilil Ciclases , Infecções Pneumocócicas/prevenção & controle , Proteínas de Bactérias/genética , Vacina contra Coqueluche , Vacinas Pneumocócicas , Imunidade , Anticorpos Antibacterianos , Camundongos Endogâmicos BALB C
6.
Exp Biol Med (Maywood) ; 248(8): 677-684, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37012663

RESUMO

Among sickle cell anemia (SCA) complications, proliferative sickle cell retinopathy (PSCR) is one of the most important, being responsible for visual impairment in 10-20% of affected eyes. The aim of this study was to identify differentially expressed genes (DEGs) present in pathways that may be implicated in the pathophysiology of PSCR from the transcriptome profile analysis of endothelial progenitor cells. RNA-Seq was used to compare gene expression profile of circulating endothelial colony-forming cells (ECFCs) from HbSS patients with and without PSCR. Furthermore, functional enrichment analysis and protein-protein interaction (PPI) networks were performed to gain further insights into biological functions. The differential expression analysis identified 501 DEGs, when comparing the groups with and without PSCR. Furthermore, functional enrichment analysis showed associations of the DEGs in 200 biological processes. Among these, regulation of mitogen-activated protein (MAP) kinase activity, positive regulation of phosphatidylinositol 3-kinase (PI3K), and positive regulation of Signal Transducer and Activator of Transcription (STAT) receptor signaling pathway were observed. These pathways are associated with angiogenesis, cell migration, adhesion, differentiation, and proliferation, important processes involved in PSCR pathophysiology. Moreover, our results showed an over-expression of VEGFC (vascular endothelial growth factor-C) and FLT1 (Fms-Related Receptor Tyrosine Kinase 1) genes, when comparing HbSS patients with and without PSCR. These results may indicate a possible association between VEGFC and FLT1 receptor, which may activate signaling pathways such as PI3K/AKT and MAPK/ERK and contribute to the mechanisms implicated in neovascularization. Thus, our findings contain preliminary results that may guide future studies in the field, since the molecular mechanisms of PSCR are still poorly understood.


Assuntos
Células Progenitoras Endoteliais , Doenças Retinianas , Humanos , Células Progenitoras Endoteliais/metabolismo , Transcriptoma/genética , Fator C de Crescimento do Endotélio Vascular/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Perfilação da Expressão Gênica
7.
Ophthalmic Genet ; 44(3): 246-252, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36994723

RESUMO

BACKGROUND: Primary open-angle glaucoma (POAG), the world's main cause of irreversible blindness, is an asymptomatic and neurodegenerative disease of multifactorial etiology with ethnic and geographic disparities. Multiethnic genome-wide association studies (GWAS) identified single nucleotide variants (SNVs) in ATXN2, FOXC1, and TXNRD2 loci as risk factors for POAG pathophysiology and/or endophenotypes. The aim of this case-control study was to investigate the association of the variants rs7137828 (ATXN2), rs2745572 (FOXC1), and rs35934224 (TXNRD2), as risk factors for POAG development, additionally to rs7137828 association with glaucoma clinical parameters in a Brazilian cohort from the Southeast and South regions. METHODS: This investigation comprised 506 cases and 501 controls. Variants rs2745572 and rs35934224 were genotyped through TaqMan® assays and validated by Sanger sequencing. Variant rs7137828 was genotyped exclusively by Sanger sequencing. RESULTS: The primary research outcome revealed that the variant rs7137828 (ATXN2) was associated with an increased risk for the development of POAG in the presence of the TT genotype compared to the CC genotype (p = 0.006; Odds Ratio [OR] = 1.717; Confidence Interval [CI] 95% = 1.169-2.535). There was no significant association of rs2745572 and rs35934224 genotypes with POAG. The CT genotype of the rs7137828 was associated with the vertical cup-to-disk ratio (VCDR) (p = .023) but not with the age at diagnosis or the mean deviation. CONCLUSION: Our data indicate the rs7137828 associated with increased risk for the development of POAG and VCDR in a Brazilian cohort. If validated in additional populations, these findings may enable the development of relevant strategies for early diagnosis of glaucoma in the future.


Assuntos
Glaucoma de Ângulo Aberto , Doenças Neurodegenerativas , Humanos , Glaucoma de Ângulo Aberto/genética , Glaucoma de Ângulo Aberto/diagnóstico , Estudo de Associação Genômica Ampla , Estudos de Casos e Controles , Brasil/epidemiologia , Genótipo , Fatores de Risco , Polimorfismo de Nucleotídeo Único , Predisposição Genética para Doença , Fatores de Transcrição Forkhead/genética , Ataxina-2/genética , Tiorredoxina Redutase 2/genética
8.
Vaccine, v. 41, n. 28, 4170-4182, jun. 2023
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4935

RESUMO

Streptococcus pneumoniae is a common agent of important human diseases such as otitis media, pneumonia, meningitis and sepsis. Current available vaccines that target capsular polysaccharides induce protection against invasive disease and nasopharyngeal colonization in children, yet their efficacy is limited to the serotypes included in the formulations. The virulence factor Pneumococcal Surface Protein A (PspA) interacts with host immune system and helps the bacteria to evade phagocytosis. Due to its essential role in virulence, PspA is an important vaccine candidate. Here we have tested a delivery system based on the adenylate cyclase toxin of Bordetella pertussis (CyaA) to induce immune responses against PspA in mice. CyaA was engineered to express fragments of the N-terminal region of PspAs from clades 2 and 4 (A2 and A4) and the resulting proteins were used in immunization experiments in mice. The recombinant CyaA-A2 and CyaA-A4 proteins were able to induce high levels of anti-PspA antibodies that reacted with pneumococcal strains expressing either PspA2 or PspA4. Moreover, reactivity of the antibodies against pneumococcal strains that express PspAs from clades 3 and 5 (PspA3 and PspA5) was also observed. A formulation containing CyaA-A2 and CyaA-A4 was able to protect mice against invasive pneumococcal challenges with isolates that express PspA2, PspA4 or PspA5. Moreover, a CyaA-A2-A4 fusion protein induced antibodies at similar levels and with similar reactivity as the formulation containing both proteins, and protected mice against the invasive challenge. Our results indicate that CyaA-PspA proteins are good candidates to induce broad protection against pneumococcal isolates.

9.
Nat Commun ; 13(1): 4831, 2022 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-35977933

RESUMO

Both T cells and B cells have been shown to be generated after infection with SARS-CoV-2 yet protocols or experimental models to study one or the other are less common. Here, we generate a chimeric protein (SpiN) that comprises the receptor binding domain (RBD) from Spike (S) and the nucleocapsid (N) antigens from SARS-CoV-2. Memory CD4+ and CD8+ T cells specific for SpiN could be detected in the blood of both individuals vaccinated with Coronavac SARS-CoV-2 vaccine and COVID-19 convalescent donors. In mice, SpiN elicited a strong IFN-γ response by T cells and high levels of antibodies to the inactivated virus, but not detectable neutralizing antibodies (nAbs). Importantly, immunization of Syrian hamsters and the human Angiotensin Convertase Enzyme-2-transgenic (K18-ACE-2) mice with Poly ICLC-adjuvanted SpiN promotes robust resistance to the wild type SARS-CoV-2, as indicated by viral load, lung inflammation, clinical outcome and reduction of lethality. The protection induced by SpiN was ablated by depletion of CD4+ and CD8+ T cells and not transferred by antibodies from vaccinated mice. Finally, vaccination with SpiN also protects the K18-ACE-2 mice against infection with Delta and Omicron SARS-CoV-2 isolates. Hence, vaccine formulations that elicit effector T cells specific for the N and RBD proteins may be used to improve COVID-19 vaccines and potentially circumvent the immune escape by variants of concern.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , Linfócitos T CD8-Positivos , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , Camundongos , Nucleocapsídeo , Proteínas do Nucleocapsídeo , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus
10.
Clin J Pain ; 38(7): 502-509, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35686580

RESUMO

OBJECTIVES: This systematic review examined studies that used mediation analysis to investigate the mechanisms of action of cognitive-behavioral, mind-body, and exercise-based interventions for pain and disability in people with chronic primary musculoskeletal pain. MATERIALS AND METHODS: We searched 5 electronic databases for articles that conducted mediation analyses of randomized controlled trials to either test or estimate indirect effects. RESULTS: We found 17 studies (n=4423), including 90 mediation models examining the role of 22 putative mediators on pain or disability, of which 4 had partially mediated treatment effect; 8 had mixed results, and 10 did not mediate treatment effect. The conditions studied were chronic whiplash-associated pain, chronic low back pain, chronic knee pain, and mixed group of chronic primary musculoskeletal pain. DISCUSSION: We observed that several of the studies included in our systematic review identified similar mechanisms of action, even between different interventions and conditions. However, methodological limitations were common. In conclusion, there are still substantial gaps with respect to understanding how cognitive-behavioral, mind-body, and exercise-based interventions work to reduce pain and disability in people with chronic primary musculoskeletal pain.


Assuntos
Dor Crônica , Dor Musculoesquelética , Dor Crônica/terapia , Cognição , Terapia por Exercício/métodos , Humanos , Dor Musculoesquelética/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto
11.
Inflammation ; 45(6): 2243-2255, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35715590

RESUMO

Previous studies have shown that immunosuppressive drugs impair the airway mucociliary clearance of rats. However, considering the high specificity of basiliximab (BSX) and the absence of studies reporting its side effects, our aim was to investigate whether BSX, associated or not with triple therapy, impairs the mucociliary system. Forty rats were divided into 4 groups: Control, BSX, Triple, and BSX + Triple. After 15 days of treatment, animals were euthanized and the ciliary beating frequency (CBF), mucociliary transport velocity (MCTV), neutral and acid mucin production, Muc5ac and Muc5b gene expression, inflammatory cell number, and interleukin (IL)-6 concentration were analyzed. CBF and MCTV were lower in Triple and BSX + Triple groups (p < 0.05). Neutral mucin percentage was higher in Triple group (p < 0.05), and acid mucin percentage was higher in Triple and BSX + Triple groups (p < 0.05). The Muc5ac and Muc5b gene expression was higher in Triple and BSX + Triple groups (p < 0.05). Animals from Triple and BSX + Triple groups presented fewer mononuclear cells (p < 0.05). The number of polymorphonuclear cells was higher in the Triple group (p < 0.05). In the analysis of inflammatory cells in the blood, there was a decrease in lymphocytes and an increase in neutrophils in the Triple and BSX + Triple groups (p < 0.05). The concentration of IL-6 significantly increased in the animals of the Triple and BSX + Triple groups (p < 0.05). BSX did not change the mucociliary apparatus of rats.


Assuntos
Basiliximab , Imunossupressores , Mucina-5AC , Depuração Mucociliar , Animais , Ratos , Basiliximab/farmacologia , Imunossupressores/farmacologia , Mucina-5AC/genética
12.
Pain ; 163(12): 2430-2437, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-35384931

RESUMO

ABSTRACT: Cognitive functional therapy (CFT) is a physiotherapy-led intervention that has evolved from an integration of foundational behavioral psychology and neuroscience within the physiotherapist practice directed at the multidimensional nature of chronic low back pain (CLBP). The current evidence about the comparative effectiveness of CFT for CLBP is still scarce. We aimed to investigate whether CFT is more effective than core training exercise and manual therapy (CORE-MT) in pain and disability in patients with CLBP. A total of 148 adults with CLBP were randomly assigned to receive 5 one-hour individualized sessions of either CFT (n = 74) or CORE-MT (n = 74) within a period of 8 weeks. Primary outcomes were pain intensity (numeric pain rating scale, 0-10) and disability (Oswestry Disability Index, 0-100) at 8 weeks. Patients were assessed preintervention, at 8 weeks and 6 and 12 months after the first treatment session. Altogether, 97.3% (n = 72) of patients in each intervention group completed the 8 weeks of the trial. Cognitive functional therapy was more effective than CORE-MT in disability at 8 weeks (MD = -4.75; 95% CI -8.38 to -1.11; P = 0.011, effect size= 0.55) but not in pain intensity (MD = -0.04; 95% CI -0.79 to 0.71; P = 0.916). Treatment with CFT reduced disability, but the difference was not clinically important compared with CORE-MT postintervention (short term) in patients with CLBP. There was no difference in pain intensity between interventions, and the treatment effect was not maintained in the mid-term and long-term follow-ups.


Assuntos
Dor Crônica , Terapia Cognitivo-Comportamental , Dor Lombar , Manipulações Musculoesqueléticas , Adulto , Humanos , Dor Lombar/terapia , Dor Lombar/psicologia , Terapia Cognitivo-Comportamental/métodos , Modalidades de Fisioterapia , Cognição , Terapia por Exercício/métodos , Dor Crônica/terapia , Dor Crônica/psicologia
13.
Imaging Sci Dent ; 52(1): 53-60, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35387102

RESUMO

Purpose: The aim of this study was to compare the fractal dimension (FD) measured at 2 bone sites (second cervical vertebra and mandible) on cone-beam computed tomography (CBCT). The research question was whether FD could serve as an accessory tool to refer postmenopausal women for densitometric analysis. Therefore, the reliability and accuracy of FD were evaluated. Materials and Methods: In total, 103 postmenopausal women were evaluated, of whom 52 had normal bone mineral density and 51 had osteoporosis, according to dual X-ray absorptiometry of the lumbar spine and hip. On the CBCT scans, 2 regions of interest were selected for FD analysis: 1 at the second cervical vertebra and 1 located at the mandible. The correlations between both measurements, intra- and inter-observer agreement, and the accuracy of the measurements were calculated. A P value less than 0.05 was considered to indicate statistical significance for all tests. Results: The mean FD values were significantly lower at the mandibular region of interest in osteoporotic patients than in individuals with normal bone mineral density. The areas under the curve were 0.644 (P=0.008) and 0.531 (P=0.720) for the mandibular and vertebral sites, respectively. Conclusion: FD at the vertebral site could not be used as an adjuvant tool to refer women for osteoporosis investigation. Although FD differed between women with normal BMD and osteoporosis at the mandibular site, it demonstrated low accuracy and reliability.

14.
mBio ; 13(1): e0347821, 2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35073735

RESUMO

Trans-sialidases (TS) are unusual enzymes present on the surface of Trypanosoma cruzi, the causative agent of Chagas disease. Encoded by the largest gene family in the T. cruzi genome, only few members of the TS family have catalytic activity. Active trans-sialidases (aTS) are responsible for transferring sialic acid from host glycoconjugates to mucins, also present on the parasite surface. The existence of several copies of TS genes has impaired the use of reverse genetics to study this highly polymorphic gene family. Using CRISPR-Cas9, we generated aTS knockout cell lines displaying undetectable levels of TS activity, as shown by sialylation assays and labeling with antibodies that recognize sialic acid-containing mucins. In vitro infection assays showed that disruption of aTS genes does not affect the parasite's capacity to invade cells or to escape from the parasitophorous vacuole but resulted in impaired differentiation of amastigotes into trypomastigotes and parasite egress from the cell. When inoculated into mice, aTS mutants were unable to establish infection even in the highly susceptible gamma interferon (IFN-γ) knockout mice. Mice immunized with aTS mutants were fully protected against a challenge infection with the virulent T. cruzi Y strain. Altogether, our results confirmed the role of aTS as a T. cruzi virulence factor and indicated that aTS play a major role during the late stages of intracellular development and parasite egress. Notably, mutants lacking TS activity are completely avirulent in animal models of infection and may be used as a live attenuated vaccine against Chagas disease. IMPORTANCE Trypanosoma cruzi is the causative agent of Chagas disease, a neglected tropical disease that affects approximately 6 to 8 million people and for which there is no effective treatment or vaccine. The parasite expresses a family of surface proteins, named trans-sialidases, responsible for transferring sialic acid from host glycoconjugates to parasite mucins. Although recognized as a main virulence factor, the multiple roles of these proteins during infection have not yet been fully characterized, mainly because the presence of several copies of aTS genes has impaired their study using reverse genetics. By applying CRISPR-Cas9, we generated aTS knockout parasites and showed that, although aTS parasite mutants were able to infect cells in vitro, they have an impaired capacity to egress from the infected cell. Importantly, aTS mutants lost the ability to cause infection in vivo but provided full protection against a challenge infection with a virulent strain.


Assuntos
Doença de Chagas , Parasitos , Trypanosoma cruzi , Animais , Camundongos , Trypanosoma cruzi/genética , Parasitos/metabolismo , Ácido N-Acetilneuramínico/metabolismo , Glicoproteínas/metabolismo , Doença de Chagas/parasitologia , Neuraminidase , Mucinas/metabolismo , Fatores de Virulência , Mamíferos/metabolismo
15.
Viruses ; 13(12)2021 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-34960708

RESUMO

The persistent circulation of SARS-CoV-2 represents an ongoing global threat due to the emergence of new viral variants that can sometimes evade the immune system of previously exposed or vaccinated individuals. We conducted a follow-up study of adult individuals that had received an inactivated SARS-CoV-2 vaccine, evaluating antibody production and neutralizing activity over a period of 6 months. In addition, we performed mice immunization with inactivated SARS-CoV-2, and evaluated the immune response and pathological outcomes against Gamma and Zeta variant infection. Vaccinated individuals produced high levels of antibodies with robust neutralizing activity, which was significantly reduced against Gamma and Zeta variants. Production of IgG anti-S antibodies and neutralizing activity robustly reduced after 6 months of vaccination. Immunized mice demonstrated cellular response against Gamma and Zeta variants, and after viral infection, reduced viral loads, IL-6 expression, and histopathological outcome in the lungs. TNF levels were unchanged in immunized or not immunized mice after infection with the Gamma variant. Furthermore, serum neutralization activity rapidly increases after infection with the Gamma and Zeta variants. Our data suggest that immunization with inactivated WT SARS-CoV-2 induces a promptly responsive cross-reactive immunity response against the Gamma and Zeta variants, reducing COVID-19 pathological outcomes.


Assuntos
Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , SARS-CoV-2/imunologia , Vacinas de Produtos Inativados/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , COVID-19/patologia , COVID-19/virologia , Vacinas contra COVID-19/administração & dosagem , Proteção Cruzada , Citocinas/metabolismo , Seguimentos , Humanos , Imunização , Pulmão/metabolismo , Pulmão/patologia , Camundongos , Vacinas de Produtos Inativados/administração & dosagem , Carga Viral
16.
EBioMedicine ; 73: 103642, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34678609

RESUMO

Interferons are innate and adaptive cytokines involved in many biological responses, in particular, viral infections. With the final response the result of the balance of the different types of Interferons. Cytokine storms are physiological reactions observed in humans and animals in which the innate immune system causes an uncontrolled and excessive release of pro-inflammatory signaling molecules. The excessive and prolonged presence of these cytokines can cause tissue damage, multisystem organ failure and death. The role of Interferons in virus clearance, tissue damage and cytokine storms are discussed, in view of COVID-19 caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). The imbalance of Type I, Type II and Type III Interferons during a viral infection contribute to the clinical outcome, possibly together with other cytokines, in particular, TNFα, with clear implications for clinical interventions to restore their correct balance.


Assuntos
COVID-19/patologia , Interferons/metabolismo , COVID-19/complicações , COVID-19/virologia , Síndrome da Liberação de Citocina/etiologia , Citocinas/metabolismo , Humanos , SARS-CoV-2/isolamento & purificação , Síndrome Respiratória Aguda Grave/etiologia , Índice de Gravidade de Doença
17.
Elife ; 102021 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-34310279

RESUMO

The microtubule-associated protein, doublecortin-like kinase 1 (DCLK1), is highly expressed in a range of cancers and is a prominent therapeutic target for kinase inhibitors. The physiological roles of DCLK1 kinase activity and how it is regulated remain elusive. Here, we analyze the role of mammalian DCLK1 kinase activity in regulating microtubule binding. We found that DCLK1 autophosphorylates a residue within its C-terminal tail to restrict its kinase activity and prevent aberrant hyperphosphorylation within its microtubule-binding domain. Removal of the C-terminal tail or mutation of this residue causes an increase in phosphorylation within the doublecortin domains, which abolishes microtubule binding. Therefore, autophosphorylation at specific sites within DCLK1 has diametric effects on the molecule's association with microtubules. Our results suggest a mechanism by which DCLK1 modulates its kinase activity to tune its microtubule-binding affinity. These results provide molecular insights for future therapeutic efforts related to DCLK1's role in cancer development and progression.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias/enzimologia , Neoplasias/patologia , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Quinases Semelhantes a Duplacortina , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Microtúbulos/metabolismo , Mutação , Neoplasias/genética , Neoplasias/metabolismo , Fosforilação , Ligação Proteica , Proteínas Serina-Treonina Quinases/genética
18.
Inflammopharmacology ; 29(2): 451-465, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33452968

RESUMO

The study aimed to investigate the chemical composition and the anti-inflammatory activity of the hydroethanolic rhizomes, stems, and leaf extracts of Renealmia petasites using in vitro and in vivo assays. The chemical composition of the extracts was characterized in a linear iron trap mass spectrometer. Total phenolic, flavonoid, and tannin content were determined by spectrophotometry analyses. In vitro anti-inflammatory activity was investigated in lipopolysaccharide-stimulated macrophages evaluating the influence on the production of superoxide anion (O2-), nitric oxide (NO), and the pro-inflammatory cytokines tumor necrosis factor (TNF-α) and interleukin-6 (IL-6). In vivo effects were determined using the air pouch model in which were inoculated carrageenan and thereafter treated with 50 mg/kg of the hydroethanolic extracts of R. petasites. After 4 and 24 h, the cellular influx, protein exudation, cytokines, and nitric oxide were evaluated. Eight compounds were tentatively identified in the R. petasites extracts, suggesting five diarylheptanoids, one flavonoid, and two fatty alcohols. The in vitro results showed that the extracts were capable of blocking free radicals and/or inhibiting their intracellular actions by inhibiting the production of important mediators of the inflammatory process, such as NO, O2-, TNF-α, and IL-6. In vivo, R. petasites significantly decrease the influx of leukocytes, mainly neutrophils, protein exudation, NO, TNF-α, and IL-6 concentration in the air pouch model. The results evidenced that R. petasites can be considered a promising alternative therapy for the treatment and management of osteoarthritis and other inflammatory diseases.


Assuntos
Anti-Inflamatórios/farmacologia , Inflamação/tratamento farmacológico , Extratos Vegetais/farmacologia , Zingiberaceae/química , Animais , Anti-Inflamatórios/isolamento & purificação , Carragenina , Citocinas/metabolismo , Modelos Animais de Doenças , Inflamação/patologia , Lipopolissacarídeos , Macrófagos/efeitos dos fármacos , Macrófagos/patologia , Masculino , Camundongos , Óxido Nítrico/metabolismo , Células RAW 264.7 , Fatores de Tempo
20.
EBioMedicine, v. 73, 103642, nov. 2021
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-3979

RESUMO

Interferons are innate and adaptive cytokines involved in many biological responses, in particular, viral infections. With the final response the result of the balance of the different types of Interferons. Cytokine storms are physiological reactions observed in humans and animals in which the innate immune system causes an uncontrolled and excessive release of pro-inflammatory signaling molecules. The excessive and prolonged presence of these cytokines can cause tissue damage, multisystem organ failure and death. The role of Interferons in virus clearance, tissue damage and cytokine storms are discussed, in view of COVID-19 caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). The imbalance of Type I, Type II and Type III Interferons during a viral infection contribute to the clinical outcome, possibly together with other cytokines, in particular, TNFα, with clear implications for clinical interventions to restore their correct balance.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA