RESUMEN
Development of potent vaccine for human respiratory syncytial virus (HRSV) that confers better protection than natural infection remains a global challenge. Vaccination with naked DNA is considered successful approach for the control of many viral diseases. In this study, the potential of DNA vaccination using full-length attachment gene of HRSV type A Saudi strain cloned in pcDNA3.1+ vector (pcDNA/GA) was evaluated in BALB/c mice. The expression efficiency of pcDNA/GA was first confirmed in HEp-2 cells on RNA and protein levels. Mice immunization with either pcDNA/GA or the positive control formalin-inactivated vaccine (FI-RSV) has generated significant serum antibody concentration in ELISA (7.31±0.418 and 9.76±0.006 µg/ml, respectively) with superior neutralizing activity. Similarly, both immunogens evoked robust HRSV-specific CD8+ T-cell response in ELISPOT assay compared to mice immunized with pcDNA3.1+ vector or saline (negative controls). Challenge of the immunized mice with the wild-type HRSV did not provoke clinical symptoms or mortality in any mice group. On the 7th day post-challenge, mice were euthanized and lungs were extirpated for evaluation of viral load, histopathological changes and cytokine profile. A significant diminish in the viral load and histology score were concluded in lungs of pcDNA/GA immunized mice compared to those immunized with FI-RSV and negative controls. The pulmonary cytokine profile of pcDNA/GA immunized mice displayed notable upregulation of Th1-associated cytokines while that of FI-RSV immunized mice exhibited high levels of Th2-associated cytokines. In conclusion, the DNA vaccine candidate pcDNA/GA has proven prominent efficacy and safety in mouse model, which encourages further evaluation in clinical trials.
Asunto(s)
Vacunas contra Virus Sincitial Respiratorio/inmunología , Virus Sincitial Respiratorio Humano/inmunología , Vacunas de ADN/inmunología , Animales , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Femenino , Humanos , Inmunización , Pulmón/inmunología , Pulmón/virología , Ratones , Ratones Endogámicos BALB C , Vacunas contra Virus Sincitial Respiratorio/administración & dosificación , Vacunas contra Virus Sincitial Respiratorio/genética , Virus Sincitial Respiratorio Humano/genética , Virus Sincitial Respiratorio Humano/fisiología , Linfocitos T/inmunología , Vacunas de ADN/administración & dosificación , Vacunas de ADN/genética , Vacunas de Productos Inactivados/administración & dosificación , Vacunas de Productos Inactivados/genética , Vacunas de Productos Inactivados/inmunología , Carga ViralRESUMEN
Bovine coronavirus (BCoV) is an economically significant cause of calf scours and winter dysentery of adult cattle, and may induce respiratory tract infections in cattle of all ages. Early diagnosis of BCoV helps to diminish its burden on the dairy and beef industry. Real-time RT-PCR assay for the detection of BCoV has been described, but it is relatively expensive, requires well-equipped laboratories and is not suitable for on-site screening. A novel assay, using reverse transcription recombinase polymerase amplification (RT-RPA), for the detection of BCoV is developed. The BCoV RT-RPA was rapid (10-20 min) and has an analytical sensitivity of 19 molecules. No cross-reactivity with other viruses causing bovine gastrointestinal and/or respiratory infections was observed. The assay performance on clinical samples was validated by testing 16 fecal and 14 nasal swab specimens and compared to real-time RT-PCR. Both assays provided comparable results. The RT-RPA assay was significantly more rapid than the real-time RT-PCR assay. The BCoV RT-RPA constitutes a suitable accurate, sensitive and rapid alternative to the common measures used for BCoV diagnosis. In addition, the use of a portable fluorescence reading device extends its application potential to use in the field and point-of-care diagnosis.
Asunto(s)
Enfermedades de los Bovinos/diagnóstico , Infecciones por Coronavirus/veterinaria , Coronavirus Bovino/aislamiento & purificación , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificación de Ácido Nucleico/métodos , Recombinasas/metabolismo , Transcripción Reversa , Animales , Bovinos , Enfermedades de los Bovinos/virología , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/virología , Coronavirus Bovino/genética , Heces/virología , Cavidad Nasal/virología , Sistemas de Atención de Punto , Sensibilidad y Especificidad , Factores de Tiempo , Medicina Veterinaria/métodos , Virología/métodosAsunto(s)
Vendajes , Coloides , Úlcera de la Pierna/enfermería , Poliuretanos , Anciano , Vendas Hidrocoloidales , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
A report of a clinical trial that evaluated the efficacy of a polyurethane foam dressing and a hydrocolloid dressing applied beneath a compression bandage.