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1.
Clin Microbiol Rev ; 35(3): e0021121, 2022 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-35726607

RESUMEN

Cholera, caused by Vibrio cholerae, persists in developing countries due to inadequate access to safe water, sanitation, and hygiene. There are approximately 4 million cases and 143,000 deaths each year due to cholera. The disease is transmitted fecally-orally via contaminated food or water. Severe dehydrating cholera can progress to hypovolemic shock due to the rapid loss of fluids and electrolytes, which requires a rapid infusion of intravenous (i.v.) fluids. The case fatality rate exceeds 50% without proper clinical management but can be less than 1% with prompt rehydration and antibiotics. Oral cholera vaccines (OCVs) serve as a major component of an integrated control package during outbreaks or within zones of endemicity. Water, sanitation, and hygiene (WaSH); health education; and prophylactic antibiotic treatment are additional components of the prevention and control of cholera. The World Health Organization (WHO) and the Global Task Force for Cholera Control (GTFCC) have set an ambitious goal of eliminating cholera by 2030 in high-risk areas.


Asunto(s)
Vacunas contra el Cólera , Cólera , Antibacterianos , Cólera/diagnóstico , Cólera/epidemiología , Cólera/prevención & control , Brotes de Enfermedades/prevención & control , Humanos , Agua
2.
Clin Infect Dis ; 76(2): 263-270, 2023 01 13.
Artículo en Inglés | MEDLINE | ID: mdl-36136760

RESUMEN

BACKGROUND: Cholera remains a public health threat for low- and middle-income countries, particularly in Asia and Africa. Shanchol™, an inactivated oral cholera vaccine (OCV) is currently in use globally. OCV and oral poliovirus vaccines (OPV) could be administered concomitantly, but the immunogenicity and safety of coadministration among children aged 1-3 years is unknown. METHODS: We undertook an open-label, randomized, controlled, inequality trial in Dhaka city, Bangladesh. Healthy children aged 1-3 years were randomly assigned to 1 of 3 groups: bivalent OPV (bOPV)-alone, OCV-alone, or combined bOPV + OCV and received vaccines on the day of enrollment and 28 days later. Blood samples were collected on the day of enrollment, day 28, and day 56. Serum poliovirus neutralizing antibodies and vibriocidal antibodies against Vibrio cholerae O1 were assessed using microneutralization assays. RESULTS: A total of 579 children aged 1‒3 years were recruited, 193 children per group. More than 90% of the children completed visits at day 56. Few adverse events following immunization were recorded and were equivalent among study arms. On day 28, 60% (90% confidence interval: 53%-67%) and 54% (46%-61%) of participants with co-administration of bOPV + OCV responded to polioviruses type 1 and 3, respectively, compared to 55% (47%-62%) and 46% (38%-53%) in the bOPV-only group. Additionally, >50% of participants showed a ≥4-fold increase in vibriocidal antibody titer responses on day 28, comparable to the responses observed in OCV-only arm. CONCLUSIONS: Co-administration of bOPV and OCV is safe and effective in children aged 1-3 years and can be cost-beneficial. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov (NCT03581734).


Asunto(s)
Vacunas contra el Cólera , Cólera , Poliomielitis , Poliovirus , Humanos , Niño , Lactante , Preescolar , Bangladesh , Cólera/prevención & control , Vacuna Antipolio Oral , Vacunas de Productos Inactivados , Administración Oral , Poliomielitis/prevención & control
3.
J Med Virol ; 95(1): e28260, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36305515

RESUMEN

Several viruses are known to be associated with the development of certain cancers, including human papilloma virus (HPV), an established causative agent for a range of anogenital and head and neck cancers. However, the causality has been based on the presence of the virus, or its genetic material, in the sampled tumors. We have long wondered if viruses cause cancer via a "hit and run" mechanism such that they are no longer present in the resulting tumors. Here, we hypothesize that the absence of viral genes from the tumor does not necessarily exclude the viral aetiology. To test this, we used an HPV-driven oropharyngeal cancer (OPC) tumor model and CRISPR to delete the viral oncogene, E7. Indeed, the genetic removal of HPV E7 oncogene eliminates tumors in vivo. Remarkably, E7 deleted tumors recurred over time and develop new mutations not previously seen in HPV+ OPC tumors. Importantly, a number of these new mutations are found to be already present in HPV- OPC tumors.


Asunto(s)
Neoplasias de Cabeza y Cuello , Proteínas Oncogénicas Virales , Neoplasias Orofaríngeas , Infecciones por Papillomavirus , Humanos , Virus del Papiloma Humano , Proteínas Oncogénicas Virales/genética , Infecciones por Papillomavirus/patología , Proteínas Represoras/genética , Recurrencia Local de Neoplasia , Neoplasias Orofaríngeas/complicaciones , Neoplasias Orofaríngeas/patología , Proteínas E7 de Papillomavirus/genética
4.
Virus Genes ; 59(2): 312-316, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36474086

RESUMEN

Clinical and pre-clinical work for a number of cancer types has demonstrated relatively positive outcomes and effective tumour regression when the level and function of p53, a well-established tumour suppressor, is restored. Human papillomavirus (HPV)-driven cancers encode the E6 oncoprotein, which leads to p53 degradation, to allow the carcinogenic process to proceed. Indeed, there have been several attempts to revive p53 function in HPV-driven cancers by both pharmacological and genetic means to increase p53 bioavailability. Here, we employed a CRISPR activation (CRISPRa) approach to overcome HPV-mediated silencing of p53 by hyperexpressing the p53 gene promoter. Our data show that CRISPRa-mediated hyperexpression of p53 leads to HPV+ cervical cancer cell killing and the reduction of cell proliferation. This proof-of-concept data suggest that increasing p53 bioavailability may potentially be a promising therapeutic approach for the treatment of HPV-driven cancers.


Asunto(s)
Proteínas Oncogénicas Virales , Infecciones por Papillomavirus , Neoplasias del Cuello Uterino , Femenino , Humanos , Neoplasias del Cuello Uterino/genética , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Virus del Papiloma Humano , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/genética , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Proteínas Oncogénicas Virales/genética , Proteínas Oncogénicas Virales/metabolismo , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/metabolismo
5.
Mol Ther ; 29(7): 2219-2226, 2021 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-33992805

RESUMEN

Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in humans. Despite several emerging vaccines, there remains no verifiable therapeutic targeted specifically to the virus. Here we present a highly effective small interfering RNA (siRNA) therapeutic against SARS-CoV-2 infection using a novel lipid nanoparticle (LNP) delivery system. Multiple siRNAs targeting highly conserved regions of the SARS-CoV-2 virus were screened, and three candidate siRNAs emerged that effectively inhibit the virus by greater than 90% either alone or in combination with one another. We simultaneously developed and screened two novel LNP formulations for the delivery of these candidate siRNA therapeutics to the lungs, an organ that incurs immense damage during SARS-CoV-2 infection. Encapsulation of siRNAs in these LNPs followed by in vivo injection demonstrated robust repression of virus in the lungs and a pronounced survival advantage to the treated mice. Our LNP-siRNA approaches are scalable and can be administered upon the first sign of SARS-CoV-2 infection in humans. We suggest that an siRNA-LNP therapeutic approach could prove highly useful in treating COVID-19 disease as an adjunctive therapy to current vaccine strategies.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , Sistemas de Liberación de Medicamentos/métodos , Lípidos/química , Nanopartículas/química , ARN Bicatenario/administración & dosificación , ARN Interferente Pequeño/administración & dosificación , ARN Interferente Pequeño/genética , SARS-CoV-2/genética , Administración Intravenosa , Enzima Convertidora de Angiotensina 2/genética , Animales , COVID-19/metabolismo , COVID-19/virología , Femenino , Silenciador del Gen , Células HEK293 , Humanos , Pulmón/metabolismo , Masculino , Ratones , Ratones Transgénicos , ARN Bicatenario/genética , ARN Viral/genética , Transcriptoma/efectos de los fármacos , Resultado del Tratamiento
6.
Mol Ther ; 27(12): 2091-2099, 2019 12 04.
Artículo en Inglés | MEDLINE | ID: mdl-31537455

RESUMEN

The recent advancements in CRISPR/Cas9 engineering have resulted in the development of more targeted and potentially safer gene therapies. The challenge in the cancer setting is knowing the driver oncogenes responsible, and the translation of these therapies is hindered by effective and safe delivery methods to target organs with minimal systemic toxicities, on-target specificity of gene editing, and demonstrated lack of long-term adverse events. Using a model system based on cervical cancer, which is driven by the ongoing expression of the human papillomavirus E6 and E7 proteins, we show that CRISPR/Cas9 delivered systemically in vivo using PEGylated liposomes results in tumor elimination and complete survival in treated animals. We compared treatment and editing efficiency of two Cas9 variants, wild-type (WT) Cas9 and the highly specific FokI-dCas9, and showed that the latter was not effective. We also explored high-fidelity repair but found that repair was inefficient, occurring in 6%-8% of cells, whereas non-homologous end joining (NHEJ) was highly efficient, occurring in ∼80% of the cells. Finally, we explored the post gene-editing events in tumors and showed that cell death is induced by apoptosis. Overall, our work demonstrates that in vivo CRISPR/Cas editing treatment of preexisting tumors is completely effective despite the large payloads.


Asunto(s)
Sistemas CRISPR-Cas , Sistemas de Liberación de Medicamentos , Terapia Genética , Proteínas Oncogénicas Virales/genética , Papillomaviridae/genética , Infecciones por Papillomavirus/complicaciones , Neoplasias del Cuello Uterino/terapia , Animales , Proteínas de Unión al ADN/antagonistas & inhibidores , Proteínas de Unión al ADN/genética , Femenino , Edición Génica , Humanos , Liposomas/administración & dosificación , Ratones , Proteínas Oncogénicas Virales/antagonistas & inhibidores , Infecciones por Papillomavirus/virología , Proteínas Represoras/antagonistas & inhibidores , Proteínas Represoras/genética , Células Tumorales Cultivadas , Neoplasias del Cuello Uterino/genética , Neoplasias del Cuello Uterino/virología
7.
Curr Microbiol ; 77(9): 2356-2364, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32377819

RESUMEN

Piperacillin (Pip) is a broad spectrum ß-lactam against most Gram-positive and Gram-negative aerobic and anaerobic bacteria. However, bacterial resistance restricts its benefits for the treatment of infectious diseases. Recently, nanoliposomal systems have been investigated as encouraging strategies to address this issue owing to their immense potential. We aimed to encapsulate Pip in liposomal nanoparticles and study their antibacterial activities in vitro against Pseudomonas aeruginosa (P. aeruginosa). Different liposomes were prepared based on the freeze-drying of a monophase solution method. Then, they were characterized in terms of size, zeta potential, polydispersity-index, and morphology. For further analysis, spectra of ATR-FTIR and XRD were taken for liposomal Pip. Encapsulation efficiency (EE) was determined via agar diffusion assay. Also, minimum inhibitory concentrations (MICs) were investigated by the standard broth macro-dilution method. The liposomes were from 100.9 to 444.13 nm with z-potential of - 30.70 to - 10.57 mV. EE of the selected formulation was 53.1%. TEM results showed that the liposomes were nanosized and almost spherical. ATR-FTIR results confirmed the full encapsulation of Pip in nanoliposomes. The X-ray pattern indicated that the liposomal Pip was amorphous. The MIC (10.6 µg/ml) of the nanoliposomal Pip against P. aeruginosa was one-half of the MIC (21.25 µg/ml) of free Pip for the same organisms. Considering four aspects (nanosized liposomes, no need for sterilization, suitable EE and enhanced antibacterial effects), this preparation method seems promising and may be used to overcome the bacterial resistance relative to Pip.


Asunto(s)
Antibacterianos , Piperacilina , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Liposomas , Pruebas de Sensibilidad Microbiana , Pseudomonas aeruginosa
8.
J Cell Biochem ; 120(6): 9203-9212, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30507008

RESUMEN

BACKGROUND: Considering the complex nature of gastrointestinal cancer, different methods including surgery, radiotherapy, and chemotherapy are considered for the treatment. Novel strategies including silencing of oncogenes using safe delivery systems could be considered as a novel approach in colorectal cancer treatment. The aim of this study was to investigate the silencing effect of high mobility group A2 (HMGA2) small interfering RNA (siRNA)-loaded nanoliposomes on gastrointestinal cancers. METHODS: The siRNA-lipoplexes were prepared using dioleoyl trimethylammonium propane (DOTAP)/cholesterol (Chol)/1, 2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) through the freeze-drying of a monophase solution method. The size, polydispersity index (PDI), and zeta-potential of nanoliposomes were determined using Zetasizer analyzer. The morphology of the nanoliposomes was determined by transmission electron microscopy (TEM). The agarose gel-retardation assay was carried out to confirm the loading of siRNAs into liposome. The silencing of the HMGA2 in cancer cells was evaluated by quantitative reverse-transcription polymerase chain reaction (qRT-PCR). The effect of liposomes on cell cytotoxicity was studied by MTT assay. The inhibitory effect of siRNA-loaded liposomes was evaluated by a wound-healing assay. The apoptosis induction was investigated via the annexin V/propidium iodide assay. RESULTS: The size, PDI, and zeta-potential of the prepared liposomes were found to be 350 nm, 0.67, and 86.3 mV, respectively. They were spherical in shape and could efficiently associate with siRNA. The results of gene silencing showed that the optimum condition of HMGA2 silencing was 80 pmol HMGA2 and 24 hours after treatment in each cancer cell lines. MTT assays indicated that silencing of HMGA2 in optimal condition could reduce the viability of the cancer cells more than 60% in the three cell lines. The result of the apoptosis assay showed more than 50% of the cell deaths related to the apoptosis in all three cell lines. The gene expression evaluation confirmed that apoptosis was induced via the intrinsic pathway inducing both caspase-3 and -9 expressions. Also, the reduction in Bcl2 expression confirmed the activation apoptosis pathway in the treated cancer cells. The wound-healing assay showed the suppression of cancer cell migration after treatment with the prepared nanoliposomes. CONCLUSION: The results of this study showed the HMGA2 siRNA-loaded nanoliposomes could be effective in the treatment of gastrointestinal cancers.


Asunto(s)
Apoptosis/fisiología , Neoplasias Gastrointestinales/metabolismo , Proteína HMGA2/metabolismo , ARN Interferente Pequeño/metabolismo , Apoptosis/genética , Línea Celular Tumoral , Neoplasias Gastrointestinales/genética , Silenciador del Gen/fisiología , Células HCT116 , Proteína HMGA2/genética , Humanos , Liposomas/química , Microscopía Electrónica de Transmisión , ARN Interferente Pequeño/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Cicatrización de Heridas/genética , Cicatrización de Heridas/fisiología
9.
Biochim Biophys Acta ; 1859(8): 1034-42, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27321990

RESUMEN

Sequence-specific degradation of homologous mRNA is the main mechanism by which short-interfering RNAs (siRNAs) suppress gene expression. Generally, it is assumed that the mRNA fragments resulting from Ago2 cleavage are rapidly degraded, thus making the transcript translation-incompetent. However, the molecular mechanisms involved in the post-cleavage mRNA decay are not completely understood and the fate of cleavage intermediates has been poorly studied. Using specific siRNAs and short-hairpin RNAs (shRNAs) we show that the 5' and 3' mRNA cleavage fragments of human papilloma virus type 16 (HPV-16) E6/7 mRNA, over-expressed in cervical malignancies, are unevenly degraded. Intriguingly, the 5' mRNA fragment was more abundant and displayed a greater stability than the corresponding 3' mRNA fragment in RNAi-treated cells. Further analysis revealed that the 5' mRNA fragment was polysome-associated, indicating its active translation, and this was further confirmed by using tagged E7 protein to show that C-terminally truncated proteins were produced in treated cells. Overall, our findings provide new insight into the degradation of siRNA-targeted transcripts and show that RNAi can alter protein expression in cells as a result of preferential stabilization and translation of the 5' cleavage fragment. These results challenge the current model of siRNA-mediated RNAi and provide a significant step forward towards understanding non-canonical pathways of siRNA gene silencing.


Asunto(s)
Células Epiteliales/metabolismo , Silenciador del Gen , Proteínas E7 de Papillomavirus/metabolismo , Biosíntesis de Proteínas , ARN Mensajero/metabolismo , Animales , Línea Celular Tumoral , Cuello del Útero/metabolismo , Cuello del Útero/patología , Cuello del Útero/virología , Células Epiteliales/patología , Células Epiteliales/virología , Femenino , Células HeLa , Interacciones Huésped-Patógeno , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/metabolismo , Humanos , Ratones , Proteínas E7 de Papillomavirus/genética , Polirribosomas/genética , Polirribosomas/metabolismo , Estabilidad del ARN , ARN Mensajero/antagonistas & inhibidores , ARN Mensajero/genética , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo
10.
BMC Cancer ; 17(1): 792, 2017 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-29178862

RESUMEN

BACKGROUND: There is a dramatic rise in the incidence of Human papillomavirus (HPV) - associated head and neck squamous cell carcinoma (HNSCC) in the world, with considerable variation by geography, gender and ethnicity. Little is known about the situation in Bangladesh, where tobacco- and areca nut-related head and neck cancers (HNCs) are the most common cancers in men. We aimed to determine the prevalence of HPV in HNSCC in Bangladesh and to explore the possible value of cell cycle markers in clinical diagnostic settings. METHODS: One hundred and ninety six archival HNSCC tissue samples were analysed for the presence of HPV DNA. The DNA quality was assured, and then amplified using a nested PCR approach. The typing of HPV was performed by automated DNA sequencing. Cellular markers p53, Cyclin D1 and pRb were tested on all samples by immunohistochemistry (IHC), as well as p16 as a putative surrogate for the detection of HPV. RESULTS: HPV DNA was detected in 36/174 (~21%) samples: 36% of cancers from the oropharynx; 31% of oral cancers, and 22% from the larynx. HPV-16 was most common, being present in 33 samples, followed by HPV-33 (2 samples) and HPV-31 (1 sample). Twenty-eight out of 174 samples were positive for p16, predominantly in HPV-positive tissues (p < 0.001). No statistically significant association was observed between the cellular markers and HPV DNA positive cases. However, p16 positivity had excellent predictive value for the presence of HPV by PCR. CONCLUSION: There is a significant burden of HPV-associated HNSCC in Bangladesh, particularly in the oropharynx but also in oral and laryngeal cancers. Whilst a combination of PCR-based DNA detection and p16 IHC is useful, the latter has excellent specificity, acceptable sensitivity and good predictive value for carriage of HPV in this population and should be used for prognostic evaluation and treatment planning of all HNSCC patients in South Asia, as in the Western world.


Asunto(s)
Neoplasias de Cabeza y Cuello/epidemiología , Neoplasias de Cabeza y Cuello/etiología , Papillomaviridae/clasificación , Papillomaviridae/genética , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/virología , Adulto , Anciano , Bangladesh/epidemiología , Biomarcadores de Tumor , ADN Viral , Femenino , Genotipo , Neoplasias de Cabeza y Cuello/metabolismo , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Vigilancia de la Población , Prevalencia , Adulto Joven
11.
Bioorg Med Chem ; 24(18): 4372-4380, 2016 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-27475535

RESUMEN

Immunotherapy is one of the most promising strategies for the treatment of cancer. Human papillomavirus (HPV) is responsible for virtually all cases of cervical cancer. The main purpose of a therapeutic HPV vaccine is to stimulate CD8(+) cytotoxic T lymphocytes (CTLs) that can eradicate HPV infected cells. HPV oncoproteins E6 and E7 are continuously expressed and are essential for maintaining the growth of HPV-associated tumor cells. We designed polymer-based multi-antigenic formulations/constructs that were comprised of the E6 and E7 peptide epitopes. We developed an N-terminus-based epitope conjugation to conjugate two unprotected peptides to poly tert-butyl acrylate. This method allowed for the incorporation of the two antigens into a polymeric dendrimer in a strictly equimolar ratio. The most effective formulations eliminated tumors in up to 50% of treated mice. Tumor recurrence was not observed up to 3months post initial challenge.


Asunto(s)
Antígenos/química , Vacunas contra Papillomavirus/uso terapéutico , Péptidos/química , Polímeros/química , Neoplasias del Cuello Uterino/prevención & control , Secuencia de Aminoácidos , Animales , Cromatografía Líquida de Alta Presión , Epítopos/química , Epítopos/inmunología , Femenino , Ratones , Ratones Endogámicos C57BL , Vacunas contra Papillomavirus/química , Vacunas contra Papillomavirus/inmunología , Espectrometría de Masa por Ionización de Electrospray
12.
Bioorg Med Chem Lett ; 25(23): 5570-5, 2015 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-26514746

RESUMEN

Human papillomaviruses (HPVs) are associated with various cancers, with HPV16 linked to more than half of cervical cancer cases. Vaccines to prevent HPV infection and cancer development have proven effective, but are not useful in individuals with prior HPV exposure. Treatment vaccines to eradicate or control HPV-associated lesions are therefore desirable for these patients. Herein we describe the development of a process to enable the production of semisynthetic vaccines based on the site-specific attachment of synthetic bacterial lipid analogs (e.g., Pam2Cys) to a non-oncogenic mutant HPV16 E7 protein to generate molecularly defined vaccines. Many cytotoxic lymphocyte (CTL) epitopes from E7 are delivered by this approach; potentially ensuring that large numbers of immunized individuals can generate CTLs to clear HPV infected cells. Delivery of this construct reduced the growth of HPV16-associated tumors in a TC1 mouse model, the effects of which were better than the potent CTL epitope HPV16 E7(44-57) administered with Montanide ISA51 adjuvant.


Asunto(s)
Adyuvantes Inmunológicos/uso terapéutico , Vacunas contra el Cáncer/uso terapéutico , Lipopéptidos/química , Neoplasias/tratamiento farmacológico , Proteínas E7 de Papillomavirus/efectos de los fármacos , Infecciones por Papillomavirus/terapia , Proteínas Recombinantes , Adyuvantes Inmunológicos/síntesis química , Secuencia de Aminoácidos , Animales , Vacunas contra el Cáncer/síntesis química , Técnicas de Química Sintética , Electroforesis en Gel de Poliacrilamida , Femenino , Humanos , Lipopéptidos/síntesis química , Lipopéptidos/genética , Ratones , Datos de Secuencia Molecular , Proteínas Recombinantes/química , Proteínas Recombinantes/genética
13.
Immunol Cell Biol ; 92(2): 156-63, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24217808

RESUMEN

Small interfering RNAs (siRNAs) to inhibit oncogene expression and also to activate innate immune responses via Toll-like receptor (TLR) recognition have been shown to be beneficial as anti-cancer therapy in certain cancer models. In this study, we investigated the effects of local versus systemic delivery of such immune-stimulating Dicer-substrate siRNAs (IS-DsiRNAs) on a human papillomavirus (HPV)-driven tumour model. Localized siRNA delivery using intratumour injection of siRNA was able to increase siRNA delivery to the tumour compared with intravenous (IV) delivery and potently activated innate immune responses. However, IV injection remained the more effective delivery route for reducing tumour growth. Although IS-DsiRNAs activated innate immune cells and required interferon-α (IFNα) for full effect on tumour growth, we found that potent silencing siRNA acting independently of IFNα were overall more effective at inhibiting TC-1 tumour growth. Other published work utilising IS-siRNAs have been carried out on tumour models with low levels of major histocompatibility complex (MHC)-class 1, a target of natural killer cells that are potently activated by IS-siRNA. As TC-1 cells used in our study express high levels of MHC-class I, the addition of the immunostimulatory motifs may not be as beneficial in this particular tumour model. Our data suggest that selection of siRNA profile and delivery method based on tumour environment is crucial to developing siRNA-based therapies.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Alphapapillomavirus/inmunología , Neoplasias Experimentales/tratamiento farmacológico , Infecciones por Papillomavirus/tratamiento farmacológico , ARN Interferente Pequeño/farmacología , Infecciones Tumorales por Virus/tratamiento farmacológico , Animales , Línea Celular Tumoral , Antígenos de Histocompatibilidad Clase I/inmunología , Humanos , Interferón-alfa/inmunología , Ratones , Neoplasias Experimentales/inmunología , Neoplasias Experimentales/patología , Infecciones por Papillomavirus/inmunología , Infecciones por Papillomavirus/patología , Infecciones Tumorales por Virus/inmunología , Infecciones Tumorales por Virus/patología
14.
Expert Rev Anti Infect Ther ; : 1-11, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38973346

RESUMEN

INTRODUCTION: Respiratory syncytial virus (RSV) causes bronchiolitis and other respiratory issues in immunocompromised individuals, the elderly, and children. After six decades of research, we have only recently seen the approval of two RSV vaccines, Arexvy and Abrysvo. Direct-acting antivirals against RSV have been more difficult to develop with ribavirin and palivizumab giving very modest reductions in hospitalizations and no differences in mortality. Recently, nirsevimab was licensed and has proven to be much more effective when given prophylactically. These are delivered intravenously (IV) and intramuscularly (IM), but an intranasal (IN) antiviral has several advantages in terms of ease of use, lower resource need, and acting at the site of infection. AREAS COVERED: In this paper, we review the available literature on the current pre-clinical research landscape of anti-RSV therapeutics tested for IN delivery. EXPERT OPINION: As RSV is a respiratory virus that infects both the upper and lower respiratory tracts, efforts are focused on developing a therapeutic that can be delivered via the nasal route. The rationale is to directly target the replicating virus with an obvious respiratory tract tropism. This approach will not only pave the way for a nasal delivery approach aimed at reducing respiratory viral illness but also controlling aerosol virus transmission.

15.
Antiviral Res ; 222: 105815, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38246206

RESUMEN

There remains a striking overall mortality burden of COVID-19 worldwide. Given the waning effectiveness of current SARS-CoV-2 antivirals due to the rapid emergence of new variants of concern (VOC), we employed a direct-acting molecular therapy approach using gene silencing RNA interference (RNAi) technology. In this study, we developed and screened several ultra-conserved small-interfering RNAs (siRNAs) before selecting one potent siRNA candidate for pre-clinical in vivo testing. This non-immunostimulatory, anti-SARS-CoV-2 siRNA candidate maintains its antiviral activity against all tested SARS-CoV-2 VOC and works effectively as a single agent. For the first time, significant antiviral effects in both the lungs and nasal cavities of SARS-CoV-2 infected mice were observed when this siRNA candidate was delivered intranasally (IN) as a prophylactic agent with the aid of lipid nanoparticles (LNPs). Importantly, a pre-exposure prophylactic IN-delivered anti-SARS-CoV-2 siRNA antiviral that can ameliorate viral replication in the nasal cavity could potentially prevent aerosol spread of respiratory viruses. An IN delivery approach would allow for the development of a direct-acting nasal spray approach that could be self-administered prophylactically.


Asunto(s)
COVID-19 , Animales , Ratones , ARN Interferente Pequeño/genética , COVID-19/prevención & control , Cavidad Nasal , SARS-CoV-2/genética , Antivirales/uso terapéutico , Pulmón
16.
Nucleic Acid Ther ; 34(3): 101-108, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38530082

RESUMEN

Long antisense RNAs (asRNAs) have been observed to repress HIV and other virus expression in a manner that is refractory to viral evolution. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of the coronavirus disease 2019 (COVID-19) disease, has a distinct ability to evolve resistance around antibody targeting, as was evident from the emergence of various SARS-CoV-2 spike antibody variants. Importantly, the effectiveness of current antivirals is waning due to the rapid emergence of new variants of concern, more recently the omicron variant. One means of avoiding the emergence of viral resistance is by using long asRNA to target SARS-CoV-2. Similar work has proven successful with HIV targeting by long asRNA. In this study, we describe a long asRNA targeting SARS-CoV-2 RNA-dependent RNA polymerase gene and the ability to deliver this RNA in extracellular vesicles (EVs) to repress virus expression. The observations presented in this study suggest that EV-delivered asRNAs are one means to targeting SARS-CoV-2 infection, which is both effective and broadly applicable as a means to control viral expression in the absence of mutation. This is the first demonstration of the use of engineered EVs to deliver long asRNA payloads for antiviral therapy.


Asunto(s)
COVID-19 , Vesículas Extracelulares , ARN sin Sentido , SARS-CoV-2 , Vesículas Extracelulares/genética , Vesículas Extracelulares/virología , Vesículas Extracelulares/metabolismo , SARS-CoV-2/genética , SARS-CoV-2/efectos de los fármacos , Humanos , ARN sin Sentido/genética , ARN sin Sentido/uso terapéutico , COVID-19/virología , COVID-19/genética , COVID-19/terapia , Animales , ARN Polimerasa Dependiente del ARN/genética , ARN Polimerasa Dependiente del ARN/antagonistas & inhibidores , Células Vero , Chlorocebus aethiops , Antivirales/uso terapéutico , Antivirales/farmacología , Tratamiento Farmacológico de COVID-19
17.
Biomacromolecules ; 14(8): 2798-806, 2013 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-23837675

RESUMEN

Dendrimers are structurally well-defined, synthetic polymers with sizes and physicochemical properties often resembling those of biomacromolecules (e.g., proteins). As a result, they are promising candidates for peptide-based vaccine delivery platforms. Herein, we established a synthetic pathway to conjugate a human papillomavirus (HPV) E7 protein-derived peptide antigen to a star-polymer to create a macromolecular vaccine candidate to treat HPV-related cancers. These conjugates were able to reduce tumor growth and eradicate E7-expressing TC-1 tumors in mice after a single immunization, without the help of any external adjuvant.


Asunto(s)
Adyuvantes Inmunológicos/uso terapéutico , Vacunas contra el Cáncer/uso terapéutico , Proteínas E7 de Papillomavirus/uso terapéutico , Infecciones por Papillomavirus/terapia , Fragmentos de Péptidos/uso terapéutico , Neoplasias del Cuello Uterino/terapia , Resinas Acrílicas/química , Adyuvantes Inmunológicos/síntesis química , Secuencia de Aminoácidos , Animales , Vacunas contra el Cáncer/síntesis química , Vacunas contra el Cáncer/inmunología , Células Cultivadas , Química Clic , Reacción de Cicloadición , Femenino , Humanos , Ratones , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , Trasplante de Neoplasias , Proteínas E7 de Papillomavirus/química , Proteínas E7 de Papillomavirus/inmunología , Infecciones por Papillomavirus/patología , Infecciones por Papillomavirus/virología , Fragmentos de Péptidos/química , Fragmentos de Péptidos/inmunología , Carga Tumoral , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/virología
18.
J Microbiol Immunol Infect ; 56(3): 516-525, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36934064

RESUMEN

RNA interference (RNAi) is an emerging and promising therapy for a wide range of respiratory viral infections. This highly specific suppression can be achieved by the introduction of short-interfering RNA (siRNA) into mammalian systems, resulting in the effective reduction of viral load. Unfortunately, this has been hindered by the lack of a good delivery system, especially via the intranasal (IN) route. Here, we have developed an IN siRNA encapsulated lipid nanoparticle (LNP) in vivo delivery system that is highly efficient at targeting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and respiratory syncytial virus (RSV) lung infection in vivo. Importantly, IN siRNA delivery without the aid of LNPs abolishes anti-SARS-CoV-2 activity in vivo. Our approach using LNPs as the delivery vehicle overcomes the significant barriers seen with IN delivery of siRNA therapeutics and is a significant advancement in our ability to delivery siRNAs. The study presented here demonstrates an attractive alternate delivery strategy for the prophylactic treatment of both future and emerging respiratory viral diseases.


Asunto(s)
COVID-19 , Nanopartículas , Infecciones por Virus Sincitial Respiratorio , Virus , Animales , Humanos , ARN Interferente Pequeño/genética , SARS-CoV-2/genética , Administración Intranasal , COVID-19/prevención & control , Infecciones por Virus Sincitial Respiratorio/prevención & control , Virus/genética , Pulmón , Mamíferos/genética
19.
Vaccine ; 41(19): 3137-3140, 2023 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-37061369

RESUMEN

A cluster-randomized trial of Vi-TT was conducted in Dhaka, Bangladesh, using JE vaccine as the control. A subset of 1,500 children were randomly selected on 2:1 basis (Vi-TT vs JE) to assess immune response. Blood was collected before vaccination, and on days 28, 545 and 730 post-vaccination and plasma anti-Vi-IgG response was measured. A robust, persistent antibody response was induced after single dose of Vi-TT, even after 2 years of vaccination. While there is no accepted serological antibody threshold of protection, analyzing the antibodies of children who received Vi-TT provides evidence that may later be useful in predicting population protection.


Asunto(s)
Fiebre Tifoidea , Vacunas Tifoides-Paratifoides , Humanos , Niño , Fiebre Tifoidea/prevención & control , Toxoide Tetánico , Salmonella typhi , Vacunas Conjugadas , Bangladesh , Inmunoglobulina G , Anticuerpos Antibacterianos , Vacunación , Formación de Anticuerpos
20.
Vaccine ; 41(14): 2368-2375, 2023 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-36898931

RESUMEN

The current global initiative to end Cholera by 2030 emphasizes the use of oral cholera vaccine (OCV) combined with feasible household Water-Sanitation-Hygiene (WASH) interventions. However, little is known about how improved WASH practices and behaviors and OCV interact to reduce the risk of cholera. We reanalyzed two arms of a cluster-randomized trial in urban Bangladesh, to evaluate the effectiveness of OCV given as a 2-dose regimen. One arm (30 clusters, n = 94,675) was randomized to vaccination of persons aged one year and older with OCV, and the other arm (30 clusters, n = 80,056) to no intervention. We evaluated the prevention of cholera by household WASH, classified at baseline using a previously validated rule, and OCV over 2 years of follow-up. When analyzed by assignment to OCV clusters rather than receipt of OCV, in comparison to persons living in "Not Better WASH" households in the control clusters, reduction of severe cholera (the primary outcome) was similar for persons in "Not Better WASH" households in vaccine clusters (46%, 95% CI:24,62), for persons in "Better WASH" households in the control clusters (48%, 95% CI:25,64), and for persons in "Better WASH" households in the vaccine clusters (48%, 95% CI:16,67). In contrast, when analyzed by actual receipt of a complete OCV regimen, , in comparison to persons in "Not Better WASH" households in the control clusters, protection against severe cholera increased steadily from 39% (95% CI:13,58) in residents of "Better WASH" households in the control clusters to 57% (95% CI:35,72) in vaccinated persons in "Not Better WASH" households to 63% (95% CI:21,83) in vaccinated persons in "Better WASH" households. This analysis suggests that improved household WASH and OCV received may interact to provide greater protection against cholera. However, the divergence between findings related to intent to vaccinate versus those pertaining to actual receipt of OCV underscores the need for further research on this topic.


Asunto(s)
Vacunas contra el Cólera , Cólera , Humanos , Cólera/prevención & control , Cólera/epidemiología , Agua , Bangladesh , Saneamiento , Vacunación , Higiene , Administración Oral
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