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1.
Cell ; 186(11): 2392-2409.e21, 2023 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-37164012

RESUMEN

T cell responses play an important role in protection against beta-coronavirus infections, including SARS-CoV-2, where they associate with decreased COVID-19 disease severity and duration. To enhance T cell immunity across epitopes infrequently altered in SARS-CoV-2 variants, we designed BNT162b4, an mRNA vaccine component that is intended to be combined with BNT162b2, the spike-protein-encoding vaccine. BNT162b4 encodes variant-conserved, immunogenic segments of the SARS-CoV-2 nucleocapsid, membrane, and ORF1ab proteins, targeting diverse HLA alleles. BNT162b4 elicits polyfunctional CD4+ and CD8+ T cell responses to diverse epitopes in animal models, alone or when co-administered with BNT162b2 while preserving spike-specific immunity. Importantly, we demonstrate that BNT162b4 protects hamsters from severe disease and reduces viral titers following challenge with viral variants. These data suggest that a combination of BNT162b2 and BNT162b4 could reduce COVID-19 disease severity and duration caused by circulating or future variants. BNT162b4 is currently being clinically evaluated in combination with the BA.4/BA.5 Omicron-updated bivalent BNT162b2 (NCT05541861).


Asunto(s)
Vacuna BNT162 , COVID-19 , Animales , Cricetinae , Humanos , Anticuerpos Neutralizantes , Anticuerpos Antivirales , COVID-19/prevención & control , Epítopos , SARS-CoV-2/genética
2.
Nature ; 592(7853): 283-289, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33524990

RESUMEN

A safe and effective vaccine against COVID-19 is urgently needed in quantities that are sufficient to immunize large populations. Here we report the preclinical development of two vaccine candidates (BNT162b1 and BNT162b2) that contain nucleoside-modified messenger RNA that encodes immunogens derived from the spike glycoprotein (S) of SARS-CoV-2, formulated in lipid nanoparticles. BNT162b1 encodes a soluble, secreted trimerized receptor-binding domain (known as the RBD-foldon). BNT162b2 encodes the full-length transmembrane S glycoprotein, locked in its prefusion conformation by the substitution of two residues with proline (S(K986P/V987P); hereafter, S(P2) (also known as P2 S)). The flexibly tethered RBDs of the RBD-foldon bind to human ACE2 with high avidity. Approximately 20% of the S(P2) trimers are in the two-RBD 'down', one-RBD 'up' state. In mice, one intramuscular dose of either candidate vaccine elicits a dose-dependent antibody response with high virus-entry inhibition titres and strong T-helper-1 CD4+ and IFNγ+CD8+ T cell responses. Prime-boost vaccination of rhesus macaques (Macaca mulatta) with the BNT162b candidates elicits SARS-CoV-2-neutralizing geometric mean titres that are 8.2-18.2× that of a panel of SARS-CoV-2-convalescent human sera. The vaccine candidates protect macaques against challenge with SARS-CoV-2; in particular, BNT162b2 protects the lower respiratory tract against the presence of viral RNA and shows no evidence of disease enhancement. Both candidates are being evaluated in phase I trials in Germany and the USA1-3, and BNT162b2 is being evaluated in an ongoing global phase II/III trial (NCT04380701 and NCT04368728).


Asunto(s)
Vacunas contra la COVID-19/inmunología , COVID-19/inmunología , COVID-19/prevención & control , Modelos Animales de Enfermedad , SARS-CoV-2/inmunología , Envejecimiento/inmunología , Animales , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Antígenos Virales/química , Antígenos Virales/genética , Antígenos Virales/inmunología , Vacuna BNT162 , COVID-19/sangre , COVID-19/terapia , COVID-19/virología , Vacunas contra la COVID-19/administración & dosificación , Vacunas contra la COVID-19/química , Vacunas contra la COVID-19/genética , Línea Celular , Ensayos Clínicos como Asunto , Femenino , Humanos , Inmunización Pasiva , Internacionalidad , Macaca mulatta/inmunología , Macaca mulatta/virología , Masculino , Ratones , Ratones Endogámicos BALB C , Modelos Moleculares , Multimerización de Proteína , ARN Viral/análisis , Sistema Respiratorio/inmunología , Sistema Respiratorio/virología , SARS-CoV-2/química , SARS-CoV-2/genética , Solubilidad , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/inmunología , Linfocitos T/inmunología , Vacunación , Vacunas Sintéticas/administración & dosificación , Vacunas Sintéticas/química , Vacunas Sintéticas/genética , Vacunas Sintéticas/inmunología , Sueroterapia para COVID-19 , Vacunas de ARNm
3.
Am J Dermatopathol ; 42(2): 111-116, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31599750

RESUMEN

Erythema multiforme (EM), Stevens-Johnson syndrome (SJS), and toxic epidermal necrolysis (TEN) comprise a family of mucocutaneous diseases associated with significant morbidity and mortality. Previous studies have confirmed the presence of autoantibodies to desmoplakin (Dp) I and II in patients with EM, SJS, and TEN. Truncated Dp production leads to characteristic changes visible on light microscopy: perinuclear clumping of keratin filaments and dyskeratotic keratinocyte. Based on these observations, the question arises as to whether a loss of Dp immunoreactivity in skin biopsies could serve as a diagnostic marker of EM, SJS, and TEN. This study analyzed Dp immunostaining patterns in 20 patients with EM or SJS/TEN. To assess the specificity of this approach, Dp immunostaining was also performed on specimens from patients with 5 potential histologic mimics of EM, SJS, and TEN. All of the samples from patients with EM, SJS, and TEN demonstrated absent or markedly diminished staining for Dp. A χ test demonstrated a statistically significant difference between the staining patterns in EM, SJS, and TEN and each of the other diagnostic groups that were investigated. This is the first report demonstrating statistically significant specificity of Dp staining patterns in EM/SJS/TEN as compared with other interface dermatitides.


Asunto(s)
Desmoplaquinas/biosíntesis , Eritema Multiforme/diagnóstico , Desmoplaquinas/análisis , Humanos , Inmunohistoquímica , Sensibilidad y Especificidad
4.
Nucleic Acids Res ; 45(2): 915-925, 2017 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-27599840

RESUMEN

A hallmark of defense mechanisms based on clustered regularly interspaced short palindromic repeats (CRISPR) and associated sequences (Cas) are the crRNAs that guide these complexes in the destruction of invading DNA or RNA. Three separate CRISPR-Cas systems exist in the cyanobacterium Synechocystis sp. PCC 6803. Based on genetic and transcriptomic evidence, two associated endoribonucleases, Cas6-1 and Cas6-2a, were postulated to be involved in crRNA maturation from CRISPR1 or CRISPR2, respectively. Here, we report a promiscuity of both enzymes to process in vitro not only their cognate transcripts, but also the respective non-cognate precursors, whereas they are specific in vivo Moreover, while most of the repeats serving as substrates were cleaved in vitro, some were not. RNA structure predictions suggested that the context sequence surrounding a repeat can interfere with its stable folding. Indeed, structure accuracy calculations of the hairpin motifs within the repeat sequences explained the majority of analyzed cleavage reactions, making this a good measure for predicting successful cleavage events. We conclude that the cleavage of CRISPR1 and CRISPR2 repeat instances requires a stable formation of the characteristic hairpin motif, which is similar between the two types of repeats. The influence of surrounding sequences might partially explain variations in crRNA abundances and should be considered when designing artificial CRISPR arrays.


Asunto(s)
Sistemas CRISPR-Cas , ARN/genética , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Endorribonucleasas/metabolismo , Secuencias Invertidas Repetidas , Conformación de Ácido Nucleico , Oligorribonucleótidos/química , Oligorribonucleótidos/genética , División del ARN , Ribonucleasas/metabolismo , Especificidad por Sustrato
5.
RNA Biol ; 10(5): 852-64, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23535141

RESUMEN

An RNA-based screen was performed to reveal a possible evolutionary scenario for the CRISPR-Cas systems in two cyanobacterial model strains. Following the analysis of a draft genome sequence of Synechocystis sp PCC6714, three different CRISPR-Cas systems were characterized that have different degrees of relatedness to another three CRISPR-Cas systems in Synechocystis sp PCC6803. A subtype III-B system was identified that is extremely conserved between both strains. Strong signals in northern hybridizations and the presence of different spacers (but identical repeats) indicated this system to be active, despite the absence of a known endonuclease candidate gene involved in the maturation of its crRNAs in the two strains. The other two systems were found to differ significantly from each other, with different sets of repeat-spacer arrays and different Cas genes. In view of the otherwise very close relatedness of the two analyzed strains, this is suggestive of an unknown mechanism involved in the replacement of CRISPR-Cas cassettes as a whole. Further RNA analyses revealed the accumulation of crRNAs to be impacted by environmental conditions critical for photoautotropic growth. All six systems are associated with a gene for a possible transcriptional repressor. Indeed, we identified one of these genes, sll7009, as encoding a negative regulator specific for the CRISPR1 subtype I-D system in Synechocystis sp PCC6803.


Asunto(s)
Proteínas Asociadas a CRISPR/genética , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Cianobacterias/química , Cianobacterias/genética , ARN Bacteriano/química , ARN Bacteriano/genética , Bacterias/química , Bacterias/genética , Bacterias/metabolismo , Secuencia de Bases , Proteínas Asociadas a CRISPR/química , Proteínas Asociadas a CRISPR/metabolismo , Cianobacterias/metabolismo , Evolución Molecular , Regulación Bacteriana de la Expresión Génica , Genoma Bacteriano , Datos de Secuencia Molecular , Filogenia , Procesamiento Postranscripcional del ARN , ARN Bacteriano/metabolismo , Alineación de Secuencia , Análisis de Secuencia de ADN
6.
Handb Exp Pharmacol ; (197): 171-92, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20217530

RESUMEN

Mankind has inhaled substances for medical and other reasons for thousands of years, notably resulting in the cultural manifestations of tobacco and opium smoking. Over the course of time concepts of pulmonary application, including inhalation devices and drug formulations, have been and still are being continuously developed. State of the art instruments even allow for individualized drug application by adaptation of the inhalation procedure to the breathing pattern of the patient. Pulmonary drug delivery offers promising advantages in comparison to "classical" drug administration via the oral or transcutaneous routes, which is also reflected by an increasing interest and number of marketed products for inhalation therapy. However, the lungs' efficient clearance mechanisms still limit the benefit of many therapeutic concepts. In consequence the objective of current research and development in pulmonary drug delivery is to overcome and to control drug clearance from the intended target site. Here, several of the most auspicious future drug delivery concepts are presented and discussed in order to give the reader an insight into this emerging field of medicine.


Asunto(s)
Sistemas de Liberación de Medicamentos , Pulmón/metabolismo , Preparaciones Farmacéuticas/administración & dosificación , Administración por Inhalación , Aerosoles , Animales , Terapia Genética/métodos , Humanos
7.
Altern Lab Anim ; 38(4): 285-95, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20822321

RESUMEN

The development of aerosol medicines typically involves numerous tests on animals, due to the lack of adequate in vitro models. A new in vitro method for testing pharmaceutical aerosol formulations on cell cultures was developed, consisting of an aerosolisation unit fitting a commercial dry powder inhaler (HandiHaler(c), Boehringer Ingelheim, Germany), an air-flow control unit (Akita(c), Activaero, Germany) and a custom-made sedimentation chamber. This chamber holds three Snapwell(c) inserts with monolayers of pulmonary epithelial cells. The whole set-up, referred to as the Pharmaceutical Aerosol Deposition Device On Cell Cultures (PADDOCC) system, aims to mimic the complete process of aerosol drug delivery, encompassing aerosol generation, aerosol deposition onto pulmonary epithelial cells and subsequent drug transport across this biological barrier, to facilitate the investigation of new aerosol formulations in the early stages of development. We describe here, the development of the design and the protocol for this device. By testing aerosol formulations of budesonide and salbutamol sulphate, respectively, reproducible deposition of aerosol particles on, and the integrity of, the pulmonary cell monolayer could be demonstrated.


Asunto(s)
Alternativas a las Pruebas en Animales/métodos , Técnicas de Cultivo de Célula/métodos , Aerosoles , Alternativas a las Pruebas en Animales/instrumentación , Animales , Línea Celular , Células Cultivadas/citología , Células Cultivadas/fisiología , Cromatografía Líquida de Alta Presión , Diseño de Equipo , Humanos , Reproducibilidad de los Resultados
8.
Inhal Toxicol ; 21 Suppl 1: 137-43, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19558246

RESUMEN

Inhalation therapy is still limited by the low bioavailability of the administered drugs. Advantages of the pulmonary administration site like large resorption area, low enzymatic equipment, and circumvention of the first pass effect are set into perspective by the rigid barrier properties of the alveolar region. As a consequence, the systemic bioavailability of peptides and proteins is still relatively limited, even when administered by modern pharmaceutical aerosol technologies. In the context of advanced pulmonary drug therapy the use of nanoparticles as alternative to micronsized drug formulation could be of special interest, because nanoparticles seem to overcome some cellular barriers quite efficiently. Besides such outstanding permeation properties, nanoparticles may also hold promises to escape from pulmonary clearance mechanisms and to allow for cell-specific targeting within the lung. Such opportunities and challenges of inhalative nanomedicine are reviewed in this short review.


Asunto(s)
Portadores de Fármacos , Nanomedicina , Nanopartículas , Proteínas/administración & dosificación , Tecnología Farmacéutica/métodos , Administración por Inhalación , Animales , Disponibilidad Biológica , Química Farmacéutica , Composición de Medicamentos , Humanos , Pulmón/metabolismo , Depuración Mucociliar , Proteínas/química , Proteínas/metabolismo
9.
Pharm Dev Technol ; 13(6): 523-32, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18728996

RESUMEN

Tablets are by far the most common solid oral dosage forms, and many drugs need to be granulated before they can be tableted. Increasingly roller compaction is being used as a dry granulation technique; however it is a very time and material intensive method. Thus some mini roller compactors and simulations of the roller compaction process have been developed as a means of studying the technique at small scale. An important factor in the selection of materials for roller compaction is their ability to be recompressed into tablets after the initial roller compaction and milling steps. In this paper the roller compaction process was simulated on the basis of some models by Gereg and Cappola (2002) and Zinchuk et al. (2004). An eccentric tableting machine was used to make compacts from alpha-lactose monohydrate, anhydrous beta-lactose, spray-dried lactose and microcrystalline cellulose at different maximum relative densities (rho rel,max 0.6-0.9). These compacts were milled immediately to granules with a rotary granulator. The properties of the granules were analyzed and compared to the properties of the original powders. These granules and powders were then tableted at different maximum relative densities (rho rel,max 0.75-0.95) and their properties including elastic recovery, crushing force and 3D-model were analyzed. The properties of the tablets made from the granules were compared to the properties of the tablets made from the powders to determine which excipients are most suitable for the roller compaction process. The study showed that anhydrous beta-lactose is the preferred form of lactose for use in roller compaction since compaction did not affect tablet crushing force to a large extent. With the simulation of roller compaction process one is able to find qualified materials for use in roller compaction without the necessity of a great deal of material and time.


Asunto(s)
Celulosa/química , Composición de Medicamentos/métodos , Lactosa/química , Comprimidos/química , Algoritmos , Rastreo Diferencial de Calorimetría , Fenómenos Químicos , Elasticidad , Excipientes/química , Dureza , Modelos Teóricos , Tamaño de la Partícula , Polvos/química
10.
Cell Mol Gastroenterol Hepatol ; 2(1): 40-47, 2016 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-26771000

RESUMEN

BACKGROUND & AIMS: Diabetic gastroparesis is associated with changes in interstitial cells of Cajal (ICC), neurons and smooth muscle cells in both animal models and humans. Macrophages appear to be critical to the development of cellular damage that leads to delayed gastric emptying but the mechanisms involved are not well understood. Csf1op/op (Op/Op) mice lack biologically active Csf1, resulting in the absence of Csf1-dependent tissue macrophages. The aim of this study was to use Csf1op/op mice to determine the role of macrophages in the development of delayed gastric emptying. METHODS: Animals were injected with streptozotocin to make them diabetic. Gastric emptying was determined weekly. Immunohistochemistry was used to identify macrophages and ICC networks in the gastric muscular layers. Oxidative stress was measured by serum malondialdehyde (MDA) levels. Quantitative, reverse transcription PCR was used to measure levels of mRNA. RESULTS: Csf1op/op mice had normal ICC. With onset of diabetes both Csf1op/op and wild type Csf1+/+ mice developed increased levels of oxidative stress (75.8 ± 9.1 and 41.2±13.6 nmol/mL MDA respectively). Wild type Csf1+/+ mice developed delayed gastric emptying after onset of diabetes (4/13) whereas no diabetic Csf1op/op mouse developed delayed gastric emptying (0/15, P=0.035). ICC were disrupted in diabetic wild type Csf1+/+ mice with delayed gastric emptying but remained normal in diabetic Csf1op/op mice. CONCLUSIONS: Cellular injury and development of delayed gastric emptying in diabetes requires the presence of muscle layer macrophages. Targeting macrophages may be an effective therapeutic option to prevent cellular damage and development of delayed gastric emptying in diabetes.

11.
PLoS One ; 8(2): e56470, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23441196

RESUMEN

The CRISPR-Cas (Clustered Regularly Interspaced Short Palindrome Repeats--CRISPR associated proteins) system provides adaptive immunity in archaea and bacteria. A hallmark of CRISPR-Cas is the involvement of short crRNAs that guide associated proteins in the destruction of invading DNA or RNA. We present three fundamentally distinct processing pathways in the cyanobacterium Synechocystis sp. PCC6803 for a subtype I-D (CRISPR1), and two type III systems (CRISPR2 and CRISPR3), which are located together on the plasmid pSYSA. Using high-throughput transcriptome analyses and assays of transcript accumulation we found all CRISPR loci to be highly expressed, but the individual crRNAs had profoundly varying abundances despite single transcription start sites for each array. In a computational analysis, CRISPR3 spacers with stable secondary structures displayed a greater ratio of degradation products. These structures might interfere with the loading of the crRNAs into RNP complexes, explaining the varying abundancies. The maturation of CRISPR1 and CRISPR2 transcripts depends on at least two different Cas6 proteins. Mutation of gene sll7090, encoding a Cmr2 protein led to the disappearance of all CRISPR3-derived crRNAs, providing in vivo evidence for a function of Cmr2 in the maturation, regulation of expression, Cmr complex formation or stabilization of CRISPR3 transcripts. Finally, we optimized CRISPR repeat structure prediction and the results indicate that the spacer context can influence individual repeat structures.


Asunto(s)
Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Synechocystis/genética , Synechocystis/metabolismo , Sistemas de Secreción Bacterianos , Endorribonucleasas/genética , Perfilación de la Expresión Génica , Técnicas de Inactivación de Genes , Orden Génico , Mutación , Conformación de Ácido Nucleico , Plásmidos/genética , Procesamiento Postranscripcional del ARN , Estabilidad del ARN , ARN Bacteriano/genética , ARN Bacteriano/metabolismo , Synechocystis/inmunología , Sitio de Iniciación de la Transcripción
12.
Methods Mol Biol ; 806: 31-42, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22057443

RESUMEN

The blood-air barrier formed by the alveolar epithelium of the peripheral lung is crucial for the pulmonary delivery of drugs. Most existing in vitro models mimicking the blood-air barrier are represented by tumor cells or immortalized cells and lack biological relevance due to their genetic alterations and underexpressed essential physiological functions. However, the increasing interest of aerosol administration of medicines to the respiratory system requires the development and use of representative in vitro models. Thereby, human alveolar epithelial cells (hAEpC) are a suitable test system allowing standardized toxicity and transport studies for newly developed compounds and delivery systems. The isolation, purification, and cultivation of hAEpC are described as well as their possible application in the so-called Pharmaceutical Aerosol Deposition Device On Cell Cultures (PADDOCC) mimicking the complete inhalation process of a powder aerosol in vitro.


Asunto(s)
Células Epiteliales Alveolares/citología , Separación Celular/métodos , Cultivo Primario de Células/métodos , Células Epiteliales Alveolares/metabolismo , Diferenciación Celular , Humanos
13.
Eur J Pharm Biopharm ; 77(1): 132-8, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20951200

RESUMEN

Absorption studies with aerosol formulation delivered by metered dose inhalers across cell- and tissue-based in vitro models of the pulmonary epithelia are not trivial due to the complexity of the processes involved: (i) aerosol generation and deposition, (ii) drug release from the carrier, and (iii) absorption across the epithelial air-blood barrier. In contrast to the intestinal mucosa, pulmonary epithelia are only covered by a thin film of lining fluid. Submersed cell culture systems would not allow to studying the deposition of aerosol particles and their effects on this delicate epithelial tissue. We developed a new Pharmaceutical Aerosol Deposition Device on Cell Cultures (PADDOCC) to mimic the inhalation of a single metered aerosol dose and its subsequent deposition on filter-grown pulmonary epithelial cell monolayers exposed to an air-liquid interface. The reproducibility of deposition of these dry powder aerosols and subsequent drug transport across Calu-3 monolayers with commercially available dry powder inhalers containing salbutamol sulphate or budesonide could be demonstrated. In the context of developing new dry powder aerosol formulations, PADDOCC appears as a useful tool, allowing reducing animal testing and faster translation into clinical trials.


Asunto(s)
Barrera Alveolocapilar/metabolismo , Broncodilatadores/farmacocinética , Inhaladores de Polvo Seco , Inhaladores de Dosis Medida , Mucosa Respiratoria/metabolismo , Absorción , Administración por Inhalación , Aerosoles , Albuterol/análisis , Albuterol/farmacocinética , Alternativas al Uso de Animales , Transporte Biológico , Broncodilatadores/análisis , Budesonida/análisis , Budesonida/farmacocinética , Técnicas de Cultivo de Célula , Línea Celular , Portadores de Fármacos , Impedancia Eléctrica , Humanos , Polvos , Mucosa Respiratoria/química , Solubilidad
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