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1.
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
2.
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
3.
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
4.
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
5.
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
6.
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
7.
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
8.
Cell Rep Med ; 2(10): 100420, 2021 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-34604818

RESUMO

Coronavirus disease 2019 (COVID-19), caused by the SARS-CoV-2 virus, has had a dramatic global impact on public health and social and economic infrastructures. Here, we assess the immunogenicity and anamnestic protective efficacy in rhesus macaques of an intradermal (i.d.)-delivered SARS-CoV-2 spike DNA vaccine, INO-4800, currently being evaluated in clinical trials. Vaccination with INO-4800 induced T cell responses and induced spike antigen and RBD binding antibodies with ADCP and ADCD activity. Sera from the animals neutralized both the D614 and G614 SARS-CoV-2 pseudotype viruses. Several months after vaccination, animals were challenged with SARS-CoV-2 resulting in rapid recall of anti-SARS-CoV-2 spike protein T cell and neutralizing antibody responses. These responses were associated with lower viral loads in the lung. These studies support the immune impact of INO-4800 for inducing both humoral and cellular arms of the adaptive immune system, which are likely important for providing durable protection against COVID-19 disease.


Assuntos
Anticorpos Antivirais/sangue , Vacinas contra COVID-19/administração & dosagem , COVID-19/prevenção & controle , Pulmão/virologia , Linfócitos T/imunologia , Animais , Anticorpos Neutralizantes/sangue , Vacinas contra COVID-19/uso terapêutico , Feminino , Injeções Intradérmicas , Macaca mulatta , Masculino , SARS-CoV-2/imunologia , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas de DNA/administração & dosagem , Vacinas de DNA/uso terapêutico , Carga Viral
9.
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.

10.
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
12.
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).

13.
ACS Infect Dis, v. 9, n. 7, p. 2736–2745, ago. 2021
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-3935

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.

14.
Vet World ; 13(11): 2452-2458, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33363341

RESUMO

BACKGROUND AND AIM: The use of antimicrobials in the control of mastitis is of concern in public health due to their inefficiency in targeting microorganisms. Studies with medicinal plants have risen as an alternative to the use of conventional products. The objective of this study was to evaluate the efficacy of an experimental disinfectant based on the essential oil (EO) from Lippia origanoides in preventing the development of new intramammary infections (IMI) in Holstein cows. MATERIALS AND METHODS: The conventional protocol of pre- and post-milking was used and the control (Conventional treatment [CNV]) and experimental (Experimental treatment [PEX]) products containing EO at 120 µL/mL were applied by immersion. Individual milk samples were analyzed using sheep blood agar methodologies and biochemical tests. The efficiency of the treatment was defined by the presence or absence of Staphylococcus aureus, coagulase-negative Staphylococcus, and Streptococcus spp. RESULTS: There were no clinical and subclinical mastitis cases, no lesions in the mucosal of teats, nor dirt score between groups in this study. Both treatments did not influence the occurrence of IMI. CONCLUSION: The results revealed that PEX acts efficiently against microorganisms compared to the disinfection by the conventional product demonstrating the efficacy of the alternative product on the prevention of new IMIs in dairy cows.

15.
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
16.
Nat Commun ; 11(1): 2601, 2020 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-32433465

RESUMO

The coronavirus family member, SARS-CoV-2 has been identified as the causal agent for the pandemic viral pneumonia disease, COVID-19. At this time, no vaccine is available to control further dissemination of the disease. We have previously engineered a synthetic DNA vaccine targeting the MERS coronavirus Spike (S) protein, the major surface antigen of coronaviruses, which is currently in clinical study. Here we build on this prior experience to generate a synthetic DNA-based vaccine candidate targeting SARS-CoV-2 S protein. The engineered construct, INO-4800, results in robust expression of the S protein in vitro. Following immunization of mice and guinea pigs with INO-4800 we measure antigen-specific T cell responses, functional antibodies which neutralize the SARS-CoV-2 infection and block Spike protein binding to the ACE2 receptor, and biodistribution of SARS-CoV-2 targeting antibodies to the lungs. This preliminary dataset identifies INO-4800 as a potential COVID-19 vaccine candidate, supporting further translational study.


Assuntos
Antígenos Virais/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas de DNA/imunologia , Vacinas Virais/imunologia , Enzima de Conversão de Angiotensina 2 , Animais , Anticorpos Neutralizantes/imunologia , Antígenos Virais/química , Vacinas contra COVID-19 , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Mapeamento de Epitopos , Cobaias , Imunidade Humoral , Imunoglobulina G/imunologia , Pulmão/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Coronavírus da Síndrome Respiratória do Oriente Médio , Modelos Animais , Peptidil Dipeptidase A/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Vacinas Virais/química
17.
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
18.
J Neuroimmune Pharmacol ; 14(1): 33-43, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-29995208

RESUMO

HIV-1 persists in cellular reservoirs that cannot be eliminated by antiretroviral therapy (ART). The major reservoir in infected individuals on effective ART is composed of resting memory CD4+ T cells that harbor proviral cDNA, and undergo a state of latency in which viral gene expression is minimal to absent. The CD4+ T cell reservoir has been extensively characterized. However, other HIV-1-permissive cells may contribute to HIV-1 persistence. Lentiviruses have a long recognized association with macrophages. However, the role, if any, played by macrophages in HIV-1 persistence is not well understood. Macrophages are resistant to cell death upon HIV-1 infection, and can survive for long periods of time, making them ideal host cells in which the virus might persist. Studying macrophages is challenging, as these cells reside in nearly all tissues. Moreover, detecting viral DNA or RNA in macrophages does not necessarily indicate that these cells will produce replication-competent viral particles. Currently, the gold standard assay to detect cellular reservoirs is the ex vivo quantitative viral outgrowth assay (QVOA), which requires a patient blood draw. However, macrophages reside deep within tissues that are inaccessible in living subjects, such as the central nervous system (CNS). Therefore, tools other than QVOA must be developed to identify cellular reservoirs that reside in the tissues. In this review, we will focus on the main aspects involved in HIV-1 persistence, including the molecular mechanisms of viral evasion, the main cell types responsible for harboring persistent HIV-1 and the tissue compartments that are likely to be reservoirs for HIV-1.


Assuntos
Infecções por HIV/virologia , HIV-1/fisiologia , Interações Hospedeiro-Patógeno/fisiologia , Macrófagos/virologia , Latência Viral/fisiologia , Animais , Humanos
19.
Front Microbiol ; 9: 2464, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30374342

RESUMO

Leishmania braziliensis is an intracellular parasite that resides mostly in macrophages. Both the parasite genome and the clinical disease manifestations show considerable polymorphism. Clinical syndromes caused by L. braziliensis include localized cutaneous (CL), mucosal (ML), and disseminated leishmaniasis (DL). Our prior studies showed that genetically distinct L. braziliensis clades associate with different clinical types. Herein, we hypothesized that: (1) L. braziliensis induces changes in macrophage gene expression that facilitates infection; (2) infection of macrophages with strains associated with CL (clade B), ML (clade C), or DL (clade A) will differentially affect host cell gene expression, reflecting their different pathogenic mechanisms; and (3) differences between the strains will be reflected by differences in macrophage gene expression after initial exposure to the parasite. Human monocyte derived macrophages were infected with L. braziliensis isolates from clades A, B, or C. Patterns of gene expression were compared using Affymetrix DNA microarrays. Many transcripts were significantly decreased by infection with all isolates. The most dramatically decreased transcripts encoded proteins involved in signaling pathways, apoptosis, or mitochondrial oxidative phosphorylation. Some transcripts encoding stress response proteins were up-regulated. Differences between L. braziliensis clades were observed in the magnitude of change, rather than the identity of transcripts. Isolates from subjects with metastatic disease (ML and DL) induced a greater magnitude of change than isolates from CL. We conclude that L. braziliensis enhances its intracellular survival by inhibiting macrophage pathways leading to microbicidal activity. Parasite strains destined for dissemination may exert a more profound suppression than less invasive L. braziliensis strains that remain near the cutaneous site of inoculation.

20.
Med Chem ; 14(3): 242-248, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28875856

RESUMO

BACKGROUND: Low molecular weight 1-Aryl-1H-1,2,3-triazoles are endowed with various types of biological activities, such as against cancer, HIV and bacteria. Despite the existence of six different classes of antiretroviral drugs in clinical use, HIV/AIDS continue to be an on growing public health problem. OBJECTIVE: In the present study, we synthesized and evaluated thirty 1-Aryl-1H-1,2,3-triazoles against HIV replication. METHOD: The compounds were prepared by Huisgen 1,3-dipolar cycloaddition protocol catalyzed by Cu(I) between aryl azides and propargylic alcohol followed by further esterification and etherification from a nucleophilic substitution with acid chlorides or alkyl bromides in good yields. The compounds were submitted to the inhibition of HIV replication and evaluation of their cytotoxicity. Initially, the compounds were screened at 10 µM and the most active were further evaluated in order to obtain some pharmacological parameters. RESULTS: Thirty molecules were evaluated, six were selected - because they inhibited more than 80% HIV replication. We further showed that two of these compounds are 8-times more potent, and less cytotoxic, than nevirapine, an antiretroviral drug in clinical use. CONCLUSION: We identified very simple triazoles with promissing antiretroviral activities that led to the development of new drugs against AIDS.


Assuntos
Fármacos Anti-HIV/farmacologia , Triazóis/farmacologia , Fármacos Anti-HIV/síntese química , Fármacos Anti-HIV/toxicidade , Reação de Cicloadição , Esterificação , HIV-1/efeitos dos fármacos , HIV-1/fisiologia , Humanos , Leucócitos Mononucleares/virologia , Nevirapina/farmacologia , Triazóis/síntese química , Triazóis/toxicidade , Replicação Viral/efeitos dos fármacos
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