RESUMEN
Human T cell leukemia virus type 1 (HTLV-1) as the first human retrovirus is currently a serious endemic health challenge. Despite the use of assorted molecular or serological assays for HTLV-1 detection, there are several limitations due to the lack of a confirmatory test that may affect the accuracy of the results. Herein, a novel label-free biosensor for the detection of HTLV-1 Tax gene has been reported. An electrochemical facile ecofriendly synthesis method has been demonstrated based on a synthesis of nanocomposite of reduced graphene oxide, polypyrrole, and gold nanoparticles (rGO-PPy-(l-Cys)-AuNPs) deposited on the surface of screen-printed carbon electrode. Electrochemical techniques were used to characterize and study the electrochemical behavior of the rGO-PPy-(l-Cys)-AuNPs, which exhibited a stable reference peak at 0.21 V associated with hybridization forms by applying the differential pulse voltammetry. The designed DNA biosensor presented a wide linear range from 0.1 fM to 100 µM and a low detection limit of 20 atto-molar. The proposed biosensor presented in this study provides outstanding selectivity, sensitivity, repeatability, and reproducibility.
Asunto(s)
Técnicas Biosensibles , ADN/química , Técnicas Electroquímicas , Virus Linfotrópico T Tipo 1 Humano/química , Nanocompuestos/química , Oligonucleótidos/análisis , Cisteína/química , Oro/química , Grafito/química , Humanos , Nanopartículas del Metal/química , Estructura Molecular , Tamaño de la Partícula , Polímeros/química , Pirroles/química , Propiedades de SuperficieRESUMEN
This report explains the employing of a combination test of traditional cell culture with a quantitative real-time PCR for assessment of the antiviral effect of zinc sulfate (ZnSO4) on herpes simplex virus (HSV)-infected Vero cells. Our evidence showed that the treatment with 0.3 mM ZnSO4 strongly inhibited the replication of virus progeny (MOI 0.001) at least 68-fold less. On the other hand, the IC50 demonstrated that the highest activity of ZnSO4 was at the 0.23 mM concentration.
Asunto(s)
Herpesvirus Humano 1/efectos de los fármacos , Replicación Viral/efectos de los fármacos , Sulfato de Zinc/farmacología , Animales , Antivirales/farmacología , Supervivencia Celular/efectos de los fármacos , Chlorocebus aethiops , Efecto Citopatogénico Viral/efectos de los fármacos , Replicación del ADN/efectos de los fármacos , Replicación del ADN/genética , Herpesvirus Humano 1/genética , Herpesvirus Humano 1/fisiología , Concentración 50 Inhibidora , Células Vero , Replicación Viral/genéticaRESUMEN
BACKGROUND: Human papillomavirus 16 is considered a causative agent of genital cancers. Since there is no decisive treatment, the only approach is vaccination of high-risk group. OBJECTIVE: This study aimed to produce a chimeric L1/L2 protein in Pichia Pastoris system. METHOD: To develop VLPs of chimeric L1/L2 protein HPV-16, first, a cross-neutralizing epitope of HPV-16 L2 gene was inserted into L1 HPV-16 gene. Then the chimeric L1/L2 HPV-16 was inserted in pPICZA plasmid and expressed in Pichia pastoris (P. pastoris). The final purification of VLPs was carried out by ultra-centrifugation (130000 g) using 10-40% sucrose density gradient for 4 h at 4 °C. The SDS-PAGE and western blot assay was carried out for L1-HPV-16 and L2-HPV- 16 proteins separately. Amount of 55ng of the purified VLPs was coated to the wells of ELISA for detection of L1 HPV-16 antibody and L2-HPV-16 antibody by ELISA test separately using commercial L1-HPV-16 and L2-HPV-16 antibodies. The sera of 16 patients positive for HPV-16 and 85 sera negative for HPV infections were tested for detection of HPV-16 antibody by ELISA test and the results were compared with commercial test kit. RESULTS: The formation and purified VLPs were observed by TEM and AFM. The result of purified VLPs by SDS-PAGE showed a band of 60 KD and confirmed by western blot assay. The results of ELISA for detection of L1-HPV-16 antibody and L2 -HPV-16 antibody showed positive reaction which displayed similar sensitivity with commercial test kit. CONCLUSION: The present study will pave the way for producing recombinant pan-HPV vaccine.