In silico/In vivo analysis of high-risk papillomavirus L1 and L2 conserved sequences for development of cross-subtype prophylactic vaccine

Ali Namvar,Azam Bolhassani,Gholamreza Javadi,Zahra Noormohammadi

doi:10.1038/s41598-019-51679-8

Ali Namvar, Azam Bolhassani + Show 2 more

Open Access

https://doi.org/10.1038/s41598-019-51679-8

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Abstract

Human papillomavirus (HPV) is the most common sexually transmitted infection in the world and the main cause of cervical cancer. Nowadays, the virus-like particles (VLPs) based on L1 proteins have been considered as the best candidate for vaccine development against HPV infections. Two commercial HPV (Gardasil and Cervarix) are available. These HPV VLP vaccines induce genotype-limited protection. The major impediments such as economic barriers especially gaps in financing obstructed the optimal delivery of vaccines in developing countries. Thus, many efforts are underway to develop the next generation of vaccines against other types of high-risk HPV. In this study, we developed DNA constructs (based on L1 and L2 genes) that were potentially immunogenic and highly conserved among the high-risk HPV types. The framework of analysis include (1) B-cell epitope mapping, (2) T-cell epitope mapping (i.e., CD4+ and CD8+ T cells), (3) allergenicity assessment, (4) tap transport and proteasomal cleavage, (5) population coverage, (6) global and template-based docking, and (7) data collection, analysis, and design of the L1 and L2 DNA constructs. Our data indicated the 8-epitope candidates for helper T-cell and CTL in L1 and L2 sequences. For the L1 and L2 constructs, combination of these peptides in a single universal vaccine could involve all world population by the rate of 95.55% and 96.33%, respectively. In vitro studies showed high expression rates of multiepitope L1 (~57.86%) and L2 (~68.42%) DNA constructs in HEK-293T cells. Moreover, in vivo studies indicated that the combination of L1 and L2 DNA constructs without any adjuvant or delivery system induced effective immune responses, and protected mice against C3 tumor cells (the percentage of tumor-free mice: ~66.67%). Thus, the designed L1 and L2 DNA constructs would represent promising applications for HPV vaccine development.

Highlights

Human papillomavirus (HPV) is the most common sexually transmitted infection in the world and the main cause of cervical cancer
The virus-like particles (VLPs) based on L1 proteins have been considered as the best candidate for vaccine development against HPV infections
A variable level of cross-protection has been observed against phylogenetically related HPV genotypes6, major impediments such as economic barriers especially gaps in financing obstructed the optimal delivery of vaccines in developing countries

Summary

Introduction

Human papillomavirus (HPV) is the most common sexually transmitted infection in the world and the main cause of cervical cancer. These HPV VLP vaccines induce genotype-limited protection The major impediments such as economic barriers especially gaps in financing obstructed the optimal delivery of vaccines in developing countries. A variable level of cross-protection has been observed against phylogenetically related HPV genotypes, major impediments such as economic barriers especially gaps in financing obstructed the optimal delivery of vaccines in developing countries This might be approached via locally produced generic vaccines. The combination of in silico/in vivo approaches was used to evaluate L1 and L2 proteins of high-risk HPV types (16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, and 68), and to design a pan genotype L1 and L2 constructs for development of DNA-based vaccines

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