طراحي و بهينه‌سازي آپتامر براي تشخيص ويروس‌هاي پاپيلوماي انساني پرخطر

Design an‎d optimization of aptamers for detection of High-risk human papillomaviruses

زيست فناوري

Human papillomavirus (HPV), the most common sexually transmitted infection with a DNA genome, is capable of causing skin lesions an‎d dangerous cancers. The Alpha genus of this virus is divided into high-risk an‎d low-risk groups an‎d poses a threat to the health of sexually active individuals. Accurate an‎d rapid detection of HPV types with high sensitivity, especially at low viral loads, is essential. In Iran, the common real-time PCR method, despite its accuracy, is time-consuming an‎d expensive. Therefore, the development of biosensors as a rapid, accurate, an‎d low-cost method is a desirable option for the early detection of HPV. The main objective of this research was to design an‎d develop an accurate aptamer based on the G-quadruplex structure for the rapid an‎d easy detection of high-risk HPVs. This research aimed to design an‎d develop an accurate G-quadruplex-based aptamer for the rapid an‎d simple detection of high-risk HPVs. In this study, bioinformatics methods were used to design an aptamer that could specifically bind to L1 protein of each of the high-risk HPVs under study. Subsequently, the binding of the designed aptamer to L1 protein of HPV18 was eva‎luated in the experiment using an aptamer-gold nanoparticle colorimetric system. In the bioinformatics section, after designing a library of aptamers, their stability an‎d secondary structure were investigated. Then, using the molecular docking method, the interaction between the three-dimensional structure of the designed aptamers an‎d the L1 protein of the studied HPV viruses was simulated. In the laboratory section, gold nanoparticles with spherical morphology were coated with APT43 aptamer (specific for binding to HPV18). To prevent the aggregation of gold nanoparticles in the presence of salt, the optimal concentration of APT43 was determined. The colorimetric assay showed that the gold nanoparticle-APT43 complex only changed color from red to purple in the presence of clinical samples containing HPV18 an‎d in the presence of salt within 15 minutes. This color change confirms the specific binding of the aptamer to HPV18 . In addition, this system can detect the virus up to 85 copies per milliliter. As a result, the gold nanoparticle-aptamer system designed based on bioinformatics methods has shown sufficient sensitivity an‎d specificity for the specific detection of high-risk HPVs an‎d can be used as a rapid an‎d simple diagnostic method.

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