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1.
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
2.
J Infect Dis ; 220(3): 400-410, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-30891607

RESUMO

BACKGROUND: Nonlive vaccine approaches that are simple to deliver and stable at room temperature or 2-8°C could be advantageous in controlling future Ebola virus (EBOV) outbreaks. Using an immunopotent DNA vaccine that generates protection from lethal EBOV challenge in small animals and nonhuman primates, we performed a clinical study to evaluate both intramuscular (IM) and novel intradermal (ID) DNA delivery. METHODS: Two DNA vaccine candidates (INO-4201 and INO-4202) targeting the EBOV glycoprotein (GP) were evaluated for safety, tolerability, and immunogenicity in a phase 1 clinical trial. The candidates were evaluated alone, together, or in combination with plasmid-encoded human cytokine interleukin-12 followed by in vivo electroporation using either the CELLECTRA® IM or ID delivery devices. RESULTS: The safety profile of all 5 regimens was shown to be benign, with the ID route being better tolerated. Antibodies to EBOV GP were generated by all 5 regimens with the fastest and steepest rise observed in the ID group. Cellular immune responses were generated with every regimen. CONCLUSIONS: ID delivery of INO-4201 was well tolerated and resulted in 100% seroreactivity after 2 doses and elicited interferon-γ T-cell responses in over 70% of subjects, providing a new approach for EBOV prevention in diverse populations. Clinical Trials Registration. NCT02464670.


Assuntos
Vacinas contra Ebola/efeitos adversos , Vacinas contra Ebola/imunologia , Imunidade Celular/imunologia , Imunidade Humoral/imunologia , Vacinas de DNA/efeitos adversos , Vacinas de DNA/imunologia , Adolescente , Adulto , Anticorpos Antivirais/imunologia , Ebolavirus/imunologia , Eletroporação/métodos , Feminino , Glicoproteínas/imunologia , Voluntários Saudáveis , Doença pelo Vírus Ebola/imunologia , Humanos , Injeções Intradérmicas/métodos , Interleucina-12/imunologia , Masculino , Pessoa de Meia-Idade , Temperatura , Vacinação/métodos , Adulto Jovem
3.
J Infect Dis ; 219(4): 544-555, 2019 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-30304515

RESUMO

Background: There remains an important need for prophylactic anti-Ebola virus vaccine candidates that elicit long-lasting immune responses and can be delivered to vulnerable populations that are unable to receive live-attenuated or viral vector vaccines. Methods: We designed novel synthetic anti-Ebola virus glycoprotein (EBOV-GP) DNA vaccines as a strategy to expand protective breadth against diverse EBOV strains and evaluated the impact of vaccine dosing and route of administration on protection against lethal EBOV-Makona challenge in cynomolgus macaques. Long-term immunogenicity was monitored in nonhuman primates for >1 year, followed by a 12-month boost. Results: Multiple-injection regimens of the EBOV-GP DNA vaccine, delivered by intramuscular administration followed by electroporation, were 100% protective against lethal EBOV-Makona challenge. Impressively, 2 injections of a simple, more tolerable, and dose-sparing intradermal administration followed by electroporation generated strong immunogenicity and was 100% protective against lethal challenge. In parallel, we observed that EBOV-GP DNA vaccination induced long-term immune responses in macaques that were detectable for at least 1 year after final vaccination and generated a strong recall response after the final boost. Conclusions: These data support that this simple intradermal-administered, serology-independent approach is likely important for additional study towards the goal of induction of anti-EBOV immunity in multiple at-risk populations.


Assuntos
Vacinas contra Ebola/imunologia , Ebolavirus/imunologia , Doença pelo Vírus Ebola/prevenção & controle , Vacinas de DNA/imunologia , Animais , Modelos Animais de Doenças , Vacinas contra Ebola/administração & dosagem , Feminino , Injeções Intramusculares , Macaca fascicularis , Masculino , Vacinas de DNA/administração & dosagem
4.
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
5.
Mol Ther Oncolytics ; 3: 16025, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28054033

RESUMO

We have previously demonstrated the immunogenicity of VGX-3100, a multicomponent DNA immunotherapy for the treatment of Human Papillomavirus (HPV)16/18-positive CIN2/3 in a phase 1 clinical trial. Here, we report on the ability to boost immune responses with an additional dose of VGX-3100. Patients completing our initial phase 1 trial were offered enrollment into a follow on trial consisting of a single boost dose of VGX-3100. Data show both cellular and humoral immune responses could be augmented above pre-boost levels, including the induction of interferon (IFN)γ production, tumor necrosis factor (TNF)α production, CD8+ T cell activation and the synthesis of lytic proteins. Moreover, observation of antigen-specific regulation of immune-related gene transcripts suggests the induction of a proinflammatory response following the boost. Analysis of T cell receptor (TCR) sequencing suggests the localization of putative HPV-specific T cell clones to the cervical mucosa, which underscores the putative mechanism of action of lesion regression and HPV16/18 elimination noted in our double-blind placebo-controlled phase 2B trial. Taken together, these data indicate that VGX-3100 drives the induction of robust cellular and humoral immune responses that can be augmented by a fourth "booster" dose. These data could be important in the scope of increasing the clinical efficacy rate of VGX-3100.

6.
Hum Gene Ther Methods ; 26(4): 134-46, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26222896

RESUMO

The CELLECTRA-3P dermal electroporation device (Inovio Pharmaceuticals, Plymouth Meeting, PA) has been evaluated in the clinic and shown to enhance the delivery of an influenza DNA vaccine. To understand the mechanism by which this device aids in enhancing the host immune response to DNA vaccines we investigated the expression kinetics and localization of a reporter plasmid (pGFP) delivered via the CELLECTRA-3P. Histological analysis revealed green fluorescent protein (GFP) expression as early as 1 hr posttreatment in the epidermal and dermal layers, and as early as 2 hr posttreatment in the subdermal layers. Immunofluorescence techniques identified keratinocytes, fibrocytes, dendritic-like cells, adipocytes, and myocytes as the principal cell populations transfected. We proceeded to demonstrate elicitation of robust host immune responses after plasmid DNA (pDNA) vaccination. In guinea pigs equivalent humoral (antibody binding titers) immune responses were observed between protocols using either CELLECTRA-3P or intramuscular electroporation to deliver the DNA vaccine. In nonhuman primates, robust interferon-γ enzyme-linked immunospot and protective levels of hemagglutination inhibition titers after pDNA vaccination were observed in groups treated with the CELLECTRA-3P. In conclusion, these findings may assist in the future to design efficient, tolerable DNA vaccination strategies for the clinic.


Assuntos
Eletroporação/instrumentação , Eletroporação/métodos , Expressão Gênica , Técnicas de Transferência de Genes , Plasmídeos/genética , Pele/metabolismo , Animais , Derme/metabolismo , Epiderme/metabolismo , Feminino , Genes Reporter , Proteínas de Fluorescência Verde , Cobaias , Macaca mulatta , Músculo Esquelético/metabolismo , Vacinas de DNA/administração & dosagem , Vacinas de DNA/genética , Vacinas de DNA/imunologia
7.
Hum Gene Ther Methods ; 25(6): 315-6, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25470335

RESUMO

The skin is rich in antigen-presenting cells and as such is an excellent target tissue for vaccination strategies. Electroporation is a physical delivery method that potentiates the uptake of DNA vaccines into target cells. Intradermal electroporation offers a minimally invasive solution to DNA delivery in the clinic. Here we describe the direct transfection of dendritic cells in the epidermis, using a surface dermal electroporation device, and specifically show a dendritic cell transfected with plasmid expressing green fluorescent protein. The dendritic cell has used its motile capabilities after transfection to move from the epidermis into the dermis, making its way to the lymphatic system.


Assuntos
Células Dendríticas/citologia , Eletroporação/métodos , Células Epidérmicas , Plasmídeos/administração & dosagem , Transfecção/métodos , Animais , Células Dendríticas/metabolismo , Eletroporação/instrumentação , Feminino , Corantes Fluorescentes , Genes Reporter , Proteínas de Fluorescência Verde/análise , Proteínas de Fluorescência Verde/genética , Cobaias , Microscopia Confocal
8.
Mol Ther Methods Clin Dev ; 1: 14054, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26052522

RESUMO

The immunocompetence and clinical accessibility of dermal tissue offers an appropriate and attractive target for vaccination. We previously demonstrated that pDNA injection into the skin in combination with surface electroporation (SEP), results in rapid and robust expression of the encoded antigen in the epidermis. Here, we demonstrate that intradermally EP-enhanced pDNA vaccination results in the rapid induction of a host humoral immune response. In the dermally relevant guinea pig model, we used high-resolution laser scanning confocal microscopy to observe direct dendritic cell (DC) transfections in the epidermis, to determine the migration kinetics of these cells from the epidermal layer into the dermis, and to follow them sequentially to the immediate draining lymph nodes. Furthermore, we delineate the relationship between the migration of directly transfected epidermal DCs and the generation of the host immune response. In summary, these data indicate that direct presentation of antigen to the immune system by DCs through SEP-based in vivo transfection in the epidermis, is related to the generation of a humoral immune response.

9.
Hum Vaccin Immunother ; 9(10): 2041-8, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23954979

RESUMO

In vivo electroporation (EP) has been shown to be a highly efficient non-viral method for enhancing DNA vaccine delivery and immunogenicity, when the site of immunization is the skin or muscle of animals and humans. However, the route of entry for many microbial pathogens is via the mucosal surfaces of the human body. We have previously reported on minimally invasive, surface and contactless EP devices for enhanced DNA delivery to dermal tissue. Robust antibody responses were induced following vaccine delivery in several tested animal models using these devices. Here, we investigated extending the modality of the surface device to efficiently deliver DNA vaccines to mucosal tissue. Initially, we demonstrated reporter gene expression in the epithelial layer of buccal mucosa in a guinea pig model. There was minimal tissue damage in guinea pig mucosal tissue resulting from EP. Delivery of a DNA vaccine encoding influenza virus nucleoprotein (NP) of influenza H1N1 elicited robust and sustained systemic IgG antibody responses following EP-enhanced delivery in the mucosa. Upon further analysis, IgA antibody responses were detected in vaginal washes and sustained cellular immune responses were detected in animals immunized at the oral mucosa with the surface EP device. This data confirms that DNA delivery and EP targeting mucosal tissue directly results in both robust and sustainable humoral as well as cellular immune responses without tissue damage. These responses are seen both in the mucosa and systemically in the blood. Direct DNA vaccine delivery enhanced by EP in mucosa may have important clinical applications for delivery of prophylactic and therapeutic DNA vaccines against diseases such as HIV, HPV and pneumonia that enter at mucosal sites and require both cellular and humoral immune responses for protection.


Assuntos
Eletroporação/métodos , Vacinação/métodos , Vacinas de DNA/administração & dosagem , Vacinas de DNA/imunologia , Administração através da Mucosa , Animais , Anticorpos Antivirais/sangue , Feminino , Cobaias , Imunidade nas Mucosas , Imunoglobulina A/análise , Imunoglobulina G/sangue , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/imunologia , Camundongos Endogâmicos BALB C , Mucosa Bucal/imunologia , Vagina/imunologia
10.
Vaccines (Basel) ; 1(3): 384-97, 2013 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-26344120

RESUMO

The skin is an attractive tissue for vaccination in a clinical setting due to the accessibility of the target, the ease of monitoring and most importantly the immune competent nature of the dermal tissue. While skin electroporation offers an exciting and novel future methodology for the delivery of DNA vaccines in the clinic, little is known about the actual mechanism of the approach and the elucidation of the resulting immune responses. To further understand the mechanism of this platform, the expression kinetics and localization of a reporter plasmid delivered via a surface dermal electroporation (SEP) device as well as the effect that this treatment would have on the resident immune cells in that tissue was investigated. Initially a time course (day 0 to day 21) of enhanced gene delivery with electroporation (EP) was performed to observe the localization of green fluorescent protein (GFP) expression and the kinetics of its appearance as well as clearance. Using gross imaging, GFP expression was not detected on the surface of the skin until 8 h post treatment. However, histological analysis by fluorescent microscopy revealed GFP positive cells as early as 1 h after plasmid delivery and electroporation. Peak GFP expression was observed at 24 h and the expression was maintained in skin for up to seven days. Using an antibody specific for a keratinocyte cell surface marker, reporter gene positive keratinocytes in the epidermis were identified. H&E staining of treated skin sections demonstrated an influx of monocytes and granulocytes at the EP site starting at 4 h and persisting up to day 14 post treatment. Immunological staining revealed a significant migration of lymphocytic cells to the EP site, congregating around cells expressing the delivered antigen. In conclusion, this study provides insights into the expression kinetics following EP enhanced DNA delivery targeting the dermal space. These findings may have implications in the future to design efficient DNA vaccination strategies for the clinic.

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