Rational Design and In Silico Evaluation of a Multiepitope Vaccine Targeting the uPAR for Cancer Immunotherapy.

Background: The urokinase plasminogen activator receptor (uPAR) plays a crucial role in cancer development and progression, making it an attractive target for immunotherapeutic strategies. This study aimed to develop a multiepitope vaccine targeting uPAR by incorporating T cell epitopes and a toll-like receptor 4 (TLR4) agonist as an adjuvant.

Methods: Immunoinformatics approaches were employed to predict and select immunogenic epitopes from the uPAR protein sequence. The selected epitopes were assembled into a multiepitope vaccine construct, including a TLR4 agonist derived from Mycobacterium tuberculosis as an adjuvant. The vaccine candidate underwent comprehensive in silico analyses, including antigenicity, allergenicity, physicochemical properties, and structural modeling. Molecular docking and molecular dynamics (MD) simulations were performed to evaluate the vaccine's interaction with the TLR4 receptor and assess its structural stability. Also, vector design was performed using the SnapGene software, while immune response simulations were conducted with the C-ImmSim server.

Results: The multiepitope vaccine construct comprised five cytotoxic T lymphocyte (CTL) epitopes, five helper T lymphocyte (HTL) epitopes, and the TLR4 agonist adjuvant. The vaccine was predicted to be nonallergenic, antigenic, and soluble, with favorable physicochemical properties. Molecular docking analysis revealed a strong binding affinity between the vaccine and TLR4, with a docking score of -334.37kcal/mol. MD simulations demonstrated the structural stability and rigidity of the vaccine-TLR4 complex. The computational immune simulation predicted a strong vaccine response with lasting antibody production, robust cellular immunity, and immunological memory formation.

Conclusion: The proposed multiepitope vaccine construct, consisting of carefully selected uPAR epitopes and a potent adjuvant, exhibits promising characteristics for inducing a robust immune response against cancer cells expressing uPAR. The favorable in silico results warrant further experimental validation and preclinical studies to assess the vaccine's efficacy and potential as a cancer immunotherapeutic agent.