In silico structure-based design of enhanced peptide inhibitors targeting RNA polymerase PAN-PB1C interaction.

Developing antivirals for influenza A virus (FluA) has become more challenging due to high range of antigenic mutation and increasing numbers of drug-resistant viruses. Finding a selective inhibitor to target highly conserved region of protein-protein interactions interface, thereby increasing its efficiency against drug resistant virus could be highly beneficial. In this study, we used in silico approach to derive FluAPep1 from highly conserved region, PAN-PB1C interface and generated 121 FluAPep1 analogues. Interestingly, we found that the FluAPep1 interaction region in the PAN domain are highly conserved in many FluA subtypes. Especially, FluAPep1 targets two pandemic FluA strains, H1N1/avian/2009 and H3N2/Victoria/1975. All of these FluA subtypes PAN domain (H1N1/H3N2CAN/H3N2VIC/H7N1/H7N2) were superimposed with PAN domain from H17N10 and the calculated root mean standards deviations were less than 3 Å. FlexPepDock analysis revealed that FluAPep1 exhibited higher binding affinity (score -246.155) with the PAN domain. In addition, around 86% of non-hot spot mutated peptides (FluAPep28-122) showed enhanced binding affinity with PAN domain. ToxinPred analysis confirmed that designed peptides were non-toxic. Thus, FluAPep1 and its analogues has potential to be further developed into an antiviral treatment against FluA infection.

Development of a novel thermal-sensitive multifunctional liposome with antibody conjugation to target EGFR-expressing tumors.

A novel EGFR-targeting, thermal-sensitive multifunctional liposome (TSML) was developed based on manganese-doped magnetism-engineered iron oxide nanoparticles (MnMEIOs) and gold nanorods (AuNRs) for efficient photothermal therapy and magnetic resonance (MR) imaging. An Erbitux-conjugated TSML (Erb-TSML) was encapsulated with doxorubicin and gold nanorods conjugated with manganese-doped magnetism-engineered iron oxide nanoparticles, for theranostic applications of EGFR-positive tumors. The Erb-TSML selectively targeted EGFR-positive tumors and promoted tumor destruction by laser activation. Using confocal microscopy, MR and optical imaging, we demonstrated that Erb-TSML specifically bound to A431 tumor cells. No signs of major morphological damages to the normal tissues were observed in mice treated with Erb-TSML and laser, indicating this theranostic platform protected heart against doxorubicin-induced toxicity to normal tissues. These results indicate that the Erb-TSML may be a promising diagnostic and therapeutic platform for EGFR-overexpressing tumors.