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1.
Int J Gynecol Cancer ; 33(12): 1869-1874, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-37907263

RESUMO

OBJECTIVE: To evaluate cervical cancer screening with primary human papillomavirus (HPV) testing in Mozambique, a country with one of the highest burdens of cervical cancer globally. METHODS: Women aged 30-49 years were prospectively enrolled and offered primary HPV testing using either self-collected or provider-collected specimens. Patients who tested positive for HPV underwent visual assessment for treatment using visual inspection with acetic acid to determine eligibility for thermal ablation. If ineligible, they were referred for excision with a loop electrosurgical excision procedure, for cold knife conization, or for cervical biopsy if malignancy was suspected. RESULTS: Between January 2020 and January 2023, 9014 patients underwent cervical cancer screening. Median age was 37 years (range 30-49) and 4122 women (45.7%) were patients living with HIV. Most (n=8792, 97.5%) chose self-collection. The HPV positivity rate was 31.1% overall and 39.5% among patients living with HIV. Of the 2805 HPV-positive patients, 2588 (92.3%) returned for all steps of their diagnostic work-up and treatment, including ablation (n=2383, 92.1%), loop electrosurgical excision procedure (n=169, 6.5%), and cold knife conization (n=5, 0.2%). Thirty-one patients (1.2%) were diagnosed with cancer and referred to gynecologic oncology. CONCLUSION: It is feasible to perform cervical cancer screening with primary HPV testing and follow-up in low-resource settings. Participants preferred self-collection, and the majority of screen-positive patients completed all steps of their diagnostic work-up and treatment. Our findings provide important information for further implementation and scale-up of cervical cancer screening and treatment services as part of the WHO global strategy for the elimination of cervical cancer.


Assuntos
Infecções por HIV , Infecções por Papillomavirus , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/cirurgia , Neoplasias do Colo do Útero/prevenção & controle , Infecções por Papillomavirus/diagnóstico , Detecção Precoce de Câncer/métodos , Moçambique/epidemiologia , Papillomaviridae , Programas de Rastreamento/métodos , Infecções por HIV/diagnóstico
2.
Proc Natl Acad Sci U S A ; 117(18): 9981-9990, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32300019

RESUMO

HIV-1 persists in cellular reservoirs that can reignite viremia if antiretroviral therapy (ART) is interrupted. Therefore, insight into the nature of those reservoirs may be revealed from the composition of recrudescing viremia following treatment cessation. A minor population of macrophage-tropic (M-tropic) viruses was identified in a library of recombinant viruses constructed with individual envelope genes that were obtained from plasma of six individuals undergoing analytic treatment interruption (ATI). M-tropic viruses could also be enriched from post-ATI plasma using macrophage-specific (CD14) but not CD4+ T cell-specific (CD3) antibodies, suggesting that M-tropic viruses had a macrophage origin. Molecular clock analysis indicated that the establishment of M-tropic HIV-1 variants predated ATI. Collectively, these data suggest that macrophages are a viral reservoir in HIV-1-infected individuals on effective ART and that M-tropic variants can appear in rebounding viremia when treatment is interrupted. These findings have implications for the design of curative strategies for HIV-1.


Assuntos
Relógios Biológicos/genética , Infecções por HIV/genética , HIV-1/genética , Viremia/genética , Antirretrovirais/farmacologia , Terapia Antirretroviral de Alta Atividade , Linfócitos T CD4-Positivos/patologia , Infecções por HIV/patologia , Infecções por HIV/virologia , Soropositividade para HIV , HIV-1/patogenicidade , Humanos , Macrófagos/imunologia , Macrófagos/patologia , Provírus/genética , Carga Viral/genética , Viremia/patologia , Viremia/virologia
3.
J Infect Dis ; 225(11): 1923-1932, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35079784

RESUMO

BACKGROUND: Additional severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines that are safe and effective as primary vaccines and boosters remain urgently needed to combat the coronavirus disease 2019 (COVID-19) pandemic. We describe safety and durability of immune responses following 2 primary doses and a homologous booster dose of an investigational DNA vaccine (INO-4800) targeting full-length spike antigen. METHODS: Three dosage strengths of INO-4800 (0.5 mg, 1.0 mg, and 2.0 mg) were evaluated in 120 age-stratified healthy adults. Intradermal injection of INO-4800 followed by electroporation at 0 and 4 weeks preceded an optional booster 6-10.5 months after the second dose. RESULTS: INO-4800 appeared well tolerated with no treatment-related serious adverse events. Most adverse events were mild and did not increase in frequency with age and subsequent dosing. A durable antibody response was observed 6 months following the second dose; a homologous booster dose significantly increased immune responses. Cytokine-producing T cells and activated CD8+ T cells with lytic potential were significantly increased in the 2.0-mg dose group. CONCLUSIONS: INO-4800 was well tolerated in a 2-dose primary series and homologous booster in all adults, including elderly participants. These results support further development of INO-4800 for use as primary vaccine and booster. CLINICAL TRIALS REGISTRATION: NCT04336410.


Assuntos
COVID-19 , Vacinas de DNA , Adulto , Idoso , Anticorpos Antivirais , Formação de Anticorpos , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , Imunogenicidade da Vacina , SARS-CoV-2 , Vacinação/efeitos adversos , Vacinas de DNA/efeitos adversos
4.
Int J Gynecol Cancer ; 30(9): 1292-1297, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32737122

RESUMO

BACKGROUND: Cervical cancer is the leading cause of cancer and related deaths among women in Mozambique. There is limited access to screening and few trained personnel to manage women with abnormal results. Our objective was to implement cervical cancer screening with human papillomavirus (HPV) testing, with navigation of women with abnormal results to appropriate diagnostic and treatment services. METHODS: We prospectively enrolled women aged 30-49 years living in Maputo, Mozambique, from April 2018 to September 2019. All participants underwent a pelvic examination by a nurse, and a cervical sample was collected and tested for HPV using the careHPV test (Qiagen, Gaithersburg, Maryland, USA). HPV positive women were referred for cryotherapy or, if ineligible for cryotherapy, a loop electrosurgical excision procedure. Women with findings concerning for cancer were referred to the gynecologic oncology service. RESULTS: Participants (n=898) had a median age of 38 years and 20.3% were women living with the human immunodeficiency virus. HPV positivity was 23.7% (95% confidence interval 21.0% to 26.6%); women living with human immunodeficiency virus were twice as likely to test positive for HPV as human immunodeficiency virus negative women (39.2% vs 19.9%, p<0.001). Most HPV positive women (194 of 213, 91.1%) completed all steps of their diagnostic work-up and treatment. Treatment included cryotherapy (n=158, 77.5%), loop electrosurgical excision procedure (n=30, 14.7%), or referral to a gynecologist or gynecologic oncologist (n=5, 2.5%). Of eight invasive cervical cancers, 5 (2.8%) were diagnosed in women living with human immunodeficiency virus and 3 (0.4%) in human immunodeficiency virus negative women (p=0.01). CONCLUSION: Cervical cancer screening with HPV testing, including appropriate follow-up and treatment, was feasible in our study cohort in Mozambique. Women living with human immunodeficiency virus appear to be at a significantly higher risk for HPV infection and the development of invasive cervical cancer than human immunodeficiency virus negative women.


Assuntos
Papillomaviridae/patogenicidade , Neoplasias do Colo do Útero/diagnóstico , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Moçambique , Estudos Prospectivos , Neoplasias do Colo do Útero/patologia
5.
Anaerobe ; 42: 182-187, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27989928

RESUMO

The aim of the present study was to compare the potency and safety of vaccines against Clostridium botulinum (C. botulinum) type C and D formulated with chitosan as controlled release matrix and vaccines formulated in conventional manner using aluminum hydroxide. Parameters were established for the development of chitosan microspheres, using simple coacervation to standardize the use of this polymer in protein encapsulation for vaccine formulation. To formulate a single shot vaccine inactivated antigens of C. botulinum type C and D were used with original toxin titles equal to 5.2 and 6.2 log LD50/ml, respectively. For each antigen a chitosan based solution of 50 mL was prepared. Control vaccines were formulated by mixing toxoid type C and D with aluminum hydroxide [25% Al(OH)3, pH 6.3]. The toxoid sterility, innocuity and potency of vaccines were evaluated as stipulated by MAPA-BRASIL according to ministerial directive no. 23. Encapsulation efficiency of BSA in chitosan was 32.5-40.37%, while that the encapsulation efficiency to toxoid type C was 41,03% (1.94 mg/mL) and of the toxoid type D was 32.30% (1.82 mg/mL). The single shot vaccine formulated using chitosan for protein encapsulation through simple coacervation showed potency and safety similar to conventional vaccine currently used in Brazilian livestock (10 and 2 IU/mL against C. botulinum type C and D, respectively). The present work suggests that our single shot vaccine would be a good option as a cattle vaccine against these C. botulinum type C and D.


Assuntos
Vacinas Bacterianas/administração & dosagem , Botulismo/prevenção & controle , Quitosana , Animais , Anticorpos Antibacterianos/imunologia , Vacinas Bacterianas/efeitos adversos , Vacinas Bacterianas/química , Vacinas Bacterianas/imunologia , Clostridium botulinum/imunologia , Preparações de Ação Retardada , Cobaias , Veículos Farmacêuticos , Potência de Vacina
6.
Liver Int ; 35(4): 1162-71, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24814243

RESUMO

BACKGROUND & AIMS: Liver regeneration is a multistage process that unfolds gradually, with different mediators acting at different stages of regeneration. Calcium (Ca(2+) ) signalling is essential for liver regeneration. In hepatocytes, Ca(2+) signalling results from the activation of inositol 1,4,5-trisphosphate receptors (InsP3 R) of which two of the three known isoforms are expressed (InsP3 R-I and InsP3 R-II). Here, we investigated the role of the InsP3 R-I-dependent Ca(2+) signals in hepatic proliferation during liver regeneration. METHODS: Partial hepatectomy (HX) in combination with knockdown of InsP3 R-I (AdsiRNA-I) was used to evaluate the role of InsP3 R-I on liver regeneration and hepatocyte proliferation, as assessed by liver to body mass ratio, PCNA expression, immunoblots and measurements of intracellular Ca(2+) signalling. RESULTS: AdsiRNA-I efficiently infected the liver as demonstrated by the expression of ß-galactosidase throughout the liver lobules. Moreover, this construct selectively and efficiently reduced the expression of InsP3 R-I, as evaluated by immunoblots. Expression of AdsiRNA-I in liver decreased peak Ca(2+) amplitude induced by vasopressin in isolated hepatocytes 2 days after HX. Reduced InsP3 R-I expression prior to HX also delayed liver regeneration, as measured by liver to body weight ratio, and reduced hepatocyte proliferation, as evaluated by PCNA staining, at the same time point. At later stages of regeneration, control hepatocytes showed a decreased expression of InsP3 R, as well as reduced InsP3 R-mediated Ca(2+) signalling, events that did not affect liver growth. CONCLUSION: Together, these results show that InsP3 R-I-dependent Ca(2+) signalling is an early triggering pathway required for liver regeneration.


Assuntos
Sinalização do Cálcio , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Regeneração Hepática , Fígado/metabolismo , Animais , Biomarcadores/metabolismo , Células CHO , Proliferação de Células , Cricetulus , Células HEK293 , Hepatectomia/métodos , Humanos , Receptores de Inositol 1,4,5-Trifosfato/genética , Fígado/fisiopatologia , Fígado/cirurgia , Masculino , Tamanho do Órgão , Antígeno Nuclear de Célula em Proliferação/metabolismo , Interferência de RNA , Ratos Sprague-Dawley , Fatores de Tempo , Transfecção
7.
Biochim Biophys Acta Proteins Proteom ; 1872(1): 140963, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37690538

RESUMO

Cellulases from anaerobic fungi are enzymes less-studied biochemically and structurally than cellulases from bacteria and aerobic fungi. Currently, only thirteen GH5 cellulases from anaerobic fungi were biochemically characterized and two crystal structures were reported. In this context, here, we report the functional and biophysical characterization of a novel multi-modular cellulosomal GH5 endoglucanase from the anaerobic gut fungus Piromyces finnis (named here PfGH5). Multiple sequences alignments indicate that PfGH5 is composed of a GH5 catalytic domain and a CBM1 carbohydrate-binding module connected through a CBM10 dockerin module. Our results showed that PfGH5 is an endoglucanase from anaerobic fungus with a large spectrum of activity. PfGH5 exhibited preference for hydrolysis of oat ß-glucan, followed by galactomannan, carboxymethyl cellulose, mannan, lichenan and barley ß-glucan, therefore displaying multi-functionality. For oat ß-glucan, PfGH5 reaches its optimum enzymatic activity at 40 °C and pH 5.5, with Km of 7.1 µM. Ion exchange chromatography analyzes revealed the production of oligosaccharides with a wide degree of polymerization indicated that PfGH5 has endoglucanase activity. The ability to bind and cleave different types of carbohydrates evidence the potential of PfGH5 for use in biotechnology and provide a useful basis for future investigation and application of new anaerobic fungi enzymes.


Assuntos
Celulase , Celulases , Celulase/química , Anaerobiose , Fungos
8.
Int J Biol Macromol ; 280(Pt 1): 135596, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39276894

RESUMO

Lytic polysaccharide monooxygenases (LPMOs) are copper-dependent enzymes that oxidize polysaccharides, leading to their cleavage. LPMOs are classified into eight CAZy families (AA9-11, AA13-17), with the functionality of AA16 being poorly characterized. This study presents biochemical and structural data for an AA16 LPMO (PnAA16) from the marine sponge symbiont Peniophora sp. Phylogenetic analysis revealed that PnAA16 clusters separately from previously characterized AA16s. However, the structural modelling of PnAA16 showed the characteristic immunoglobulin-like fold of LPMOs, with a conserved his-brace motif coordinating a copper ion. The copper-bound PnAA16 showed greater thermal stability than its apo-form, highlighting copper's role in enzyme stability. Functionally, PnAA16 demonstrated oxidase activity, producing 5 µM H2O2 after 30 min, but showed 20 times lower peroxidase activity (0.27 U/g) compared to a fungal AA9. Specific activity assays indicated that PnAA16 acts only on cellohexaose, generating native celloligosaccharides (C3 to C5) and oxidized products with regioselective oxidation at C1 and C4 positions. Finally, PnAA16 boosted the activity of a cellulolytic cocktail for cellulose saccharification in the presence of ascorbic acid, hydrogen peroxide, or both. In conclusion, the present work provides insights into the AA16 family, expanding the understanding of their structural and functional relationships and biotechnological potential.

9.
Acta Ortop Bras ; 32(3): e266917, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39086846

RESUMO

Objective: After deep brain stimulation (DBS), patients with Parkinson's disease (PD) typically still present significant gait and postural stability problems, and thus additional interventions are needed. In this way, our purpose was evaluate the comparative effectiveness of treadmill training, with and without body weight support, on balance outcomes among patients with PD after DBS. Methods: Eleven patients with PD that were using bilateral subthalamic nucleus DBS were evaluated using Time Up and Go test (TUG); Berg Balance Scale (BBS) and Static Posturography. In phase 1, all subjects participated in 8-weeks of treadmill training in conjunction with conventional physiotherapy. After six weeks (wash-out), each patient then participated in a subsequent 8-weeks of treadmill training with partial body weight support. Results: After the phase 1, there were improvements on the cognitive TUG performance (Before: 15.7 ± 1,8 sec; After: 13.7 ± 3.1 sec; p < 0.01) and an increase of anteroposterior and medio-lateral body oscillation with eyes closed. After the phase 2, there were improvements in conventional (Before: 12.3 ± 2.0 sec; After: 10.7 ± 1.7 sec; p < 0.01) and cognitive (Before: 14.6 ± 3.5 sec; After: 12.5 ± 1.6 sec; p < 0.05) TUG performances. There were no significant changes in the Berg Balance Scale following either training protocol. Conclusion: Both trainings improved static and dynamic balance and had similar results; however, supported treadmill training seemed to be a potentially superior option, as patients tended to feel safer. Level of Evidence II, therapeutic studies - investigation of treatment outcomes.


Objetivo: Mesmo após a estimulação cerebral profunda (ECP), os pacientes com doença de Parkinson (DP) muitas vezes ainda apresentam problemas significativos de marcha e estabilidade postural, e, portanto, intervenções adicionais são necessárias. Avaliar a eficácia comparativa do treinamento em esteira, com e sem suporte de peso corporal, nos resultados de equilíbrio de pacientes com DP após ECP. Métodos: Onze pacientes com DP em uso de ECP bilateral do núcleo subtalâmico foram avaliados pelos testes Time Up and Go (TUG), escala de equilíbrio de Berg (EEB) e posturografia estática. Na fase 1, todos participaram de oito semanas de treinamento em esteira em conjunto com fisioterapia convencional. Após seis semanas (wash-out), cada paciente participou de oito semanas subsequentes de treinamento em esteira com suporte parcial de peso corporal. Resultados: Depois da fase 1, houve melhora no desempenho cognitivo do TUG (antes: 15,7 ± 1,8 s; depois: 13,7 ± 3,1 s; p < 0,01) e aumento da oscilação anteroposterior e médio-lateral do corpo com os olhos fechados. Após a fase 2, os resultados do TUG convencional (antes: 12,3 ± 2,0 seg; depois: 10,7 ± 1,7 seg; p < 0,01) e cognitivo (antes: 14,6 ± 3,5 s; depois: 12,5 ± 1,6 s; p < 0,05) demonstraram melhora. Os protocolos de treinamento não causaram mudanças significativas na EEB.. Conclusão: Ambos os treinos melhoraram o equilíbrio estático e dinâmico e tiveram resultados semelhantes; no entanto, o treinamento em esteira com suporte é uma opção potencialmente superior, uma vez que os pacientes tendiam a se sentir mais seguros. Nível de Evidência II, estudos terapêuticos - investigação de resultados de tratamento.

10.
Enzyme Microb Technol ; 180: 110498, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39182429

RESUMO

Dienelactone hydrolase (DLH) is one of numerous hydrolytic enzymes with an α/ß-hydrolase fold, which catalyze the hydrolysis of dienelactone to maleylacetate. The DLHs share remarkably similar tertiary structures and a conserved arrangement of catalytic residues. This study presents the crystal structure and comprehensive functional characterization of a novel thermostable DLH from the bacterium Hydrogenobacter thermophilus (HtDLH). The crystal structure of the HtDLH, solved at a resolution of about 1.67 Å, exhibits a canonical α/ß-hydrolase fold formed by eight ß-sheet strands in the core, with one buried α-helix and six others exposed to the solvent. The structure also confirmed the conserved catalytic triad of DHLs formed by Cys121, Asp170, and His202 residues. The HtDLH forms stable homodimers in solution. Functional studies showed that HtDLH has the expected esterase activity over esters with short carbon chains, such as p-nitrophenyl acetate, reaching optimal activity at pH 7.5 and 70 °C. Furthermore, HtDLH maintains more than 50 % of its activity even after incubation at 90 °C for 16 h. Interestingly, HtDLH exhibits catalytic activity towards polyethylene terephthalate (PET) monomers, including bis-1,2-hydroxyethyl terephthalate (BHET) and 1-(2-hydroxyethyl) 4-methyl terephthalate, as well as other aliphatic and aromatic esters. These findings associated with the lack of activity on amorphous PET indicate that HtDLH has characteristic of a BHET-degrading enzyme. This work expands our understanding of enzyme families involved in PET degradation, providing novel insights for plastic biorecycling through protein engineering, which could lead to eco-friendly solutions to reduce the accumulation of plastic in landfills and natural environments.


Assuntos
Hidrolases de Éster Carboxílico , Estabilidade Enzimática , Especificidade por Substrato , Cristalografia por Raios X , Hidrolases de Éster Carboxílico/metabolismo , Hidrolases de Éster Carboxílico/química , Hidrolases de Éster Carboxílico/genética , Ácidos Ftálicos/metabolismo , Ácidos Ftálicos/química , Ésteres/metabolismo , Ésteres/química , Modelos Moleculares , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Conformação Proteica , Concentração de Íons de Hidrogênio , Cinética , Hidrólise , Domínio Catalítico , Temperatura
11.
Rev Esc Enferm USP ; 47(2): 355-61, 2013 Apr.
Artigo em Português | MEDLINE | ID: mdl-23743901

RESUMO

This descriptive and cross-sectional study aimed to examine the socio-demographic/clinical aspects of health-related quality of life (HRQoL) and assess the HRQoL of onco- hematological patients undergoing chemotherapy. The data collection instrument was a socio-demographic/clinical questionnaire, the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC) QLQ-C-30. The sample consisted of 32 patients, eight of whom (25%) were diagnosed with Hodgkin's lymphoma; nine (28.12%), with non-Hodgkin's lymphoma; and 15 (46.87%), with leukemia. The data were analyzed using SPSS software. For the functional scales of the QLQ-C-30 (physical, cognitive, emotional, social and role performance), the mean scores ranged from 54.81 to 41.18, demonstrating an unsatisfactory level of functioning. In the symptom scales, there was a predominance of fatigue (64.57), insomnia (56.90) and loss of appetite (50.71). These symptoms interfered with the patients' physical functioning, demonstrating that the emotional and cognitive side effects of the treatment negatively influenced the HRQoL of the patients.


Assuntos
Doença de Hodgkin/tratamento farmacológico , Leucemia/tratamento farmacológico , Linfoma não Hodgkin/tratamento farmacológico , Qualidade de Vida , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
12.
Hum Vaccin Immunother ; 19(3): 2281733, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38012018

RESUMO

Nucleic acid vaccines are designed based on genetic sequences (DNA or mRNA) of a target antigen to be expressed in vivo to drive a host immune response. In response to the COVID-19 pandemic, mRNA and DNA vaccines based on the SARS-CoV-2 Spike antigen were developed. Surprisingly, head-to-head characterizations of the immune responses elicited by each vaccine type has not been performed to date. Here, we have employed a range of preclinical animal models including the hamster, guinea pig, rabbit, and mouse to compare and delineate the immune response raised by DNA, administered intradermally (ID) with electroporation (EP) and mRNA vaccines (BNT162b2 or mRNA-1273), administered intramuscularly (IM), expressing the SARS-CoV-2 WT spike antigen. The results revealed clear differences in the quality and magnitude of the immune response between the two vaccine platforms. The DNA vaccine immune response was characterized by strong T cell responses, while the mRNA vaccine elicited robust humoral responses. The results may assist in guiding the disease target each vaccine type may be best matched against and suggest mechanisms to further enhance the breadth of each platform's immune response.


Assuntos
COVID-19 , Vacinas de DNA , Cricetinae , Animais , Cobaias , Humanos , Camundongos , Coelhos , Vacina BNT162 , Vacinas contra COVID-19 , Pandemias , COVID-19/prevenção & controle , SARS-CoV-2 , DNA , Modelos Animais , RNA Mensageiro , Imunidade , Anticorpos Antivirais , Glicoproteína da Espícula de Coronavírus/genética
13.
Hepatology ; 54(1): 296-306, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21503946

RESUMO

UNLABELLED: Subcellular Ca(2+) signals control a variety of responses in the liver. For example, mitochondrial Ca(2+) (Ca(mit)(2+)) regulates apoptosis, whereas Ca(2+) in the nucleus regulates cell proliferation. Because apoptosis and cell growth can be related, we investigated whether Ca(mit)(2+) also affects liver regeneration. The Ca(2+)-buffering protein parvalbumin, which was targeted to the mitochondrial matrix and fused to green fluorescent protein, was expressed in the SKHep1 liver cell line; the vector was called parvalbumin-mitochondrial targeting sequence-green fluorescent protein (PV-MITO-GFP). This construct properly localized to and effectively buffered Ca(2+) signals in the mitochondrial matrix. Additionally, the expression of PV-MITO-GFP reduced apoptosis induced by both intrinsic and extrinsic pathways. The reduction in cell death correlated with the increased expression of antiapoptotic genes [B cell lymphoma 2 (bcl-2), myeloid cell leukemia 1, and B cell lymphoma extra large] and with the decreased expression of proapoptotic genes [p53, B cell lymphoma 2-associated X protein (bax), apoptotic peptidase activating factor 1, and caspase-6]. PV-MITO-GFP was also expressed in hepatocytes in vivo with an adenoviral delivery system. Ca(mit)(2+) buffering in hepatocytes accelerated liver regeneration after partial hepatectomy, and this effect was associated with the increased expression of bcl-2 and the decreased expression of bax. CONCLUSION: Together, these results reveal an essential role for Ca(mit)(2+) in hepatocyte proliferation and liver regeneration, which may be mediated by the regulation of apoptosis.


Assuntos
Apoptose/fisiologia , Cálcio/metabolismo , Regeneração Hepática/fisiologia , Mitocôndrias Hepáticas/metabolismo , Animais , Sinalização do Cálcio/fisiologia , Proliferação de Células , Masculino , Modelos Animais , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Sprague-Dawley , Proteína X Associada a bcl-2/metabolismo
14.
Vaccine ; 40(21): 2960-2969, 2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-35428500

RESUMO

The enhanced transmissibility and immune evasion associated with emerging SARS-CoV-2 variants demands the development of next-generation vaccines capable of inducing superior protection amid a shifting pandemic landscape. Since a portion of the global population harbors some level of immunity from vaccines based on the original Wuhan-Hu-1 SARS-CoV-2 sequence or natural infection, an important question going forward is whether this immunity can be boosted by next-generation vaccines that target emerging variants while simultaneously maintaining long-term protection against existing strains. Here, we evaluated the immunogenicity of INO-4800, our synthetic DNA vaccine candidate for COVID-19 currently in clinical evaluation, and INO-4802, a next-generation DNA vaccine designed to broadly target emerging SARS-CoV-2 variants, as booster vaccines in nonhuman primates. Rhesus macaques primed over one year prior with the first-generation INO-4800 vaccine were boosted with either INO-4800 or INO-4802 in homologous or heterologous prime-boost regimens. Both boosting schedules led to an expansion of T cells and antibody responses which were characterized by improved neutralizing and ACE2 blocking activity across wild-type SARS-CoV-2 as well as multiple variants of concern. These data illustrate the durability of immunity following vaccination with INO-4800 and additionally support the use of either INO-4800 or INO-4802 in prime-boost regimens.


Assuntos
COVID-19 , Vacinas de DNA , Vacinas Virais , Animais , Formação de Anticorpos , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , Macaca mulatta , Camundongos , Camundongos Endogâmicos BALB C , SARS-CoV-2 , Vacinação
15.
Nat Commun ; 13(1): 5886, 2022 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-36202799

RESUMO

Monoclonal antibody therapy has played an important role against SARS-CoV-2. Strategies to deliver functional, antibody-based therapeutics with improved in vivo durability are needed to supplement current efforts and reach underserved populations. Here, we compare recombinant mAbs COV2-2196 and COV2-2130, which compromise clinical cocktail Tixagevimab/Cilgavimab, with optimized nucleic acid-launched forms. Functional profiling of in vivo-expressed, DNA-encoded monoclonal antibodies (DMAbs) demonstrated similar specificity, broad antiviral potency and equivalent protective efficacy in multiple animal challenge models of SARS-CoV-2 prophylaxis compared to protein delivery. In PK studies, DNA-delivery drove significant serum antibody titers that were better maintained compared to protein administration. Furthermore, cryo-EM studies performed on serum-derived DMAbs provide the first high-resolution visualization of in vivo-launched antibodies, revealing new interactions that may promote cooperative binding to trimeric antigen and broad activity against VoC including Omicron lineages. These data support the further study of DMAb technology in the development and delivery of valuable biologics.


Assuntos
Produtos Biológicos , COVID-19 , Ácidos Nucleicos , Animais , Anticorpos Monoclonais , Anticorpos Neutralizantes , Anticorpos Antivirais , Antivirais/farmacologia , Antivirais/uso terapêutico , COVID-19/prevenção & controle , DNA , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/genética
16.
Cell Rep ; 38(5): 110318, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35090597

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines may target epitopes that reduce durability or increase the potential for escape from vaccine-induced immunity. Using synthetic vaccinology, we have developed rationally immune-focused SARS-CoV-2 Spike-based vaccines. Glycans can be employed to alter antibody responses to infection and vaccines. Utilizing computational modeling and in vitro screening, we have incorporated glycans into the receptor-binding domain (RBD) and assessed antigenic profiles. We demonstrate that glycan-coated RBD immunogens elicit stronger neutralizing antibodies and have engineered seven multivalent configurations. Advanced DNA delivery of engineered nanoparticle vaccines rapidly elicits potent neutralizing antibodies in guinea pigs, hamsters, and multiple mouse models, including human ACE2 and human antibody repertoire transgenics. RBD nanoparticles induce high levels of cross-neutralizing antibodies against variants of concern with durable titers beyond 6 months. Single, low-dose immunization protects against a lethal SARS-CoV-2 challenge. Single-dose coronavirus vaccines via DNA-launched nanoparticles provide a platform for rapid clinical translation of potent and durable coronavirus vaccines.


Assuntos
Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , Nanopartículas/administração & dosagem , SARS-CoV-2/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Sítios de Ligação , Vacinas contra COVID-19/química , Vacinas contra COVID-19/genética , Cricetinae , Epitopos , Cobaias , Imunogenicidade da Vacina , Camundongos , Nanopartículas/química , Vacinas Baseadas em Ácido Nucleico/administração & dosagem , Vacinas Baseadas em Ácido Nucleico/química , Vacinas Baseadas em Ácido Nucleico/genética , Vacinas Baseadas em Ácido Nucleico/imunologia , Polissacarídeos/química , Polissacarídeos/genética , Polissacarídeos/imunologia , SARS-CoV-2/química , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Potência de Vacina
17.
J Hepatol ; 55(3): 626-635, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21237226

RESUMO

BACKGROUND & AIMS: Nucleoplasmic Ca(2+) regulates cell growth in the liver, but the proteins through which this occurs are unknown. METHODS: We used Rapid Subtraction Hybridization (RaSH) to subtract genes in SKHep1 liver cells expressing the Ca(2+) buffer protein parvalbumin (PV) targeted to the nucleus, from genes in cells expressing a mutated form of nuclear-targeted PV which has one of two Ca(2+)-binding sites inactivated. The subtraction permitted the selection of genes whose expression was affected by a small alteration in nuclear Ca(2+) concentration. RESULTS: The asparaginyl endopeptidase legumain (LGMN) was identified in this screening. When Ca(2+) was buffered in the nucleus of SKHep1 cells, LGMN mRNA was decreased by 97%, in part by a transcriptional mechanism, and decreased expression at the protein level was observed by immunoblot and immunofluorescence. Treatment with hepatocyte growth factor increased LGMN expression. Knockdown of LGMN by siRNA decreased proliferation of SKHep1 cells by ∼50% as measured both by BrdU uptake and mitotic index, although an inhibitor of LGMN activity did not affect BrdU incorporation. A significant reduction in the fraction of cells in G2/M phase was seen as well. This was associated with increases in the expression of cyclins A and E. Furthermore, LGMN expression was increased in hepatocellular carcinoma cells relative to normal hepatocytes in the same specimens. CONCLUSIONS: These findings suggest a new role for LGMN and provide evidence that nuclear Ca(2+) signals regulate cell proliferation in part through the modulation of LGMN expression. Increased expression of LGMN may be involved in liver carcinogenesis.


Assuntos
Sinalização do Cálcio/fisiologia , Cálcio/metabolismo , Proliferação de Células , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/metabolismo , RNA Mensageiro/metabolismo , Carcinoma Hepatocelular/metabolismo , Núcleo Celular/metabolismo , Cisteína Endopeptidases/fisiologia , Pontos de Checagem da Fase G2 do Ciclo Celular , Técnicas de Silenciamento de Genes , Hepatócitos/metabolismo , Humanos , Células Tumorais Cultivadas
18.
ACS Infect Dis ; 7(9): 2736-2745, 2021 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-34463484

RESUMO

Multidrug-resistant bacteria represent a global health problem increasingly leading to infections that are untreatable with our existing antibiotic arsenal. Therefore, it is critical to identify novel effective antimicrobials. Venoms represent an underexplored source of potential antibiotic molecules. Here, we engineered a peptide (IsCT1-NH2) derived from the venom of the scorpion Opisthacanthus madagascariensis, whose application as an antimicrobial had been traditionally hindered by its high toxicity. Through peptide design and the knowledge obtained in preliminary studies with single and double-substituted analogs, we engineered IsCT1 derivatives with multiple amino acid substitutions to assess the impact of net charge on antimicrobial activity and toxicity. We demonstrate that increased net charge (from +3 to +6) significantly reduced toxicity toward human erythrocytes. Our lead synthetic peptide, [A]1[K]3[F]5[K]8-IsCT1-NH2 (net charge of +4), exhibited increased antimicrobial activity against Gram-negative and Gram-positive bacteria in vitro and enhanced anti-infective activity in a mouse model. Mechanism of action studies revealed that the increased antimicrobial activity of our lead molecule was due, at least in part, to its enhanced ability to permeabilize the outer membrane and depolarize the cytoplasmic membrane. In summary, we describe a simple method based on net charge tuning to turn highly toxic venom-derived peptides into viable therapeutics.


Assuntos
Anti-Infecciosos , Venenos de Escorpião , Animais , Camundongos , Testes de Sensibilidade Microbiana , Modelos Animais , Peptídeos/farmacologia , Venenos de Escorpião/toxicidade
19.
NPJ Vaccines ; 6(1): 121, 2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34650089

RESUMO

Global surveillance has identified emerging SARS-CoV-2 variants of concern (VOC) associated with broadened host specificity, pathogenicity, and immune evasion to vaccine-induced immunity. Here we compared humoral and cellular responses against SARS-CoV-2 VOC in subjects immunized with the DNA vaccine, INO-4800. INO-4800 vaccination induced neutralizing antibodies against all variants tested, with reduced levels detected against B.1.351. IFNγ T cell responses were fully maintained against all variants tested.

20.
EClinicalMedicine ; 31: 100689, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33392485

RESUMO

BACKGROUND: A vaccine against SARS-CoV-2 is of high urgency. Here the safety and immunogenicity induced by a DNA vaccine (INO-4800) targeting the full length spike antigen of SARS-CoV-2 are described. METHODS: INO-4800 was evaluated in two groups of 20 participants, receiving either 1.0 mg or 2.0 mg of vaccine intradermally followed by CELLECTRA® EP at 0 and 4 weeks. Thirty-nine subjects completed both doses; one subject in the 2.0 mg group discontinued trial participation prior to receiving the second dose. ClinicalTrials.gov identifier: NCT04336410. FINDINGS: The median age was 34.5, 55% (22/40) were men and 82.5% (33/40) white. Through week 8, only 6 related Grade 1 adverse events in 5 subjects were observed. None of these increased in frequency with the second administration. No serious adverse events were reported. All 38 subjects evaluable for immunogenicity had cellular and/or humoral immune responses following the second dose of INO-4800. By week 6, 95% (36/38) of the participants seroconverted based on their responses by generating binding (ELISA) and/or neutralizing antibodies (PRNT IC50), with responder geometric mean binding antibody titers of 655.5 [95% CI (255.6, 1681.0)] and 994.2 [95% CI (395.3, 2500.3)] in the 1.0 mg and 2.0 mg groups, respectively. For neutralizing antibody, 78% (14/18) and 84% (16/19) generated a response with corresponding geometric mean titers of 102.3 [95% CI (37.4, 280.3)] and 63.5 [95% CI (39.6, 101.8)], in the respective groups. By week 8, 74% (14/19) and 100% (19/19) of subjects generated T cell responses by IFN-É£ ELISpot assay with the median SFU per 106 PBMC of 46 [95% CI (21.1, 142.2)] and 71 [95% CI (32.2, 194.4)] in the 1.0 mg and 2.0 mg groups, respectively. Flow cytometry demonstrated a T cell response, dominated by CD8+ T cells co-producing IFN-É£ and TNF-α, without increase in IL-4. INTERPRETATION: INO-4800 demonstrated excellent safety and tolerability and was immunogenic in 100% (38/38) of the vaccinated subjects by eliciting either or both humoral or cellular immune responses. FUNDING: Coalition for Epidemic Preparedness Innovations (CEPI).

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