مقالات پذیرفته شده در نهمین کنگره بین المللی زیست پزشکی
Design of a Multi-Epitope Peptide Vaccine Against Glioblastoma Multiforme Targeting IL13Rα2: An Immuno-Informatics Approach
Design of a Multi-Epitope Peptide Vaccine Against Glioblastoma Multiforme Targeting IL13Rα2: An Immuno-Informatics Approach
Ilnaz Rahimmanesh,1,*
1. Applied Physiology Research Center, Cardiovascular Research Institute, Isfahan University of Medical Sciences, Isfahan, Iran
Introduction: Glioblastoma Multiforme (GBM) is the most aggressive primary brain tumor, notorious for its resistance to conventional therapies. Immunotherapy, particularly peptide-based vaccines, presents a novel strategy to induce a specific immune response against tumor-specific antigens. The interleukin-13 receptor alpha 2 (IL13Rα2) is an ideal target, as it is overexpressed in GBM while having limited distribution in normal brain tissue.
Methods: An immuno-informatics approach was employed to design a vaccine targeting IL13Rα2. Cytotoxic T-Lymphocyte (CTL) and B-cell epitopes were predicted from the IL13Rα2 protein sequence (UniProt ID: Q14627) using NetMHCpan-4.1 and BcePred/IEDB tools, respectively. The selected epitopes were screened for antigenicity (VaxiJen v2.0), allergenicity (AllerTOP v.2, AllergenFP), and toxicity (ToxinPred). A final multi-epitope construct was designed by linking 16 CTL and 6 B-cell epitopes with appropriate linkers (AAY and KK). The physicochemical properties, secondary structure, and 3D model of the vaccine were analyzed using ProtParam, PSIPRED, and AlphaFold 3, respectively. Molecular docking with TLR3 (PDB: 1ZIW) was performed using ClusPro 2.0 and PRODIGY to assess binding affinity. Finally, the immune response profile was simulated using the C-ImmSim server.
Results: The designed vaccine construct is 281 amino acids long with a molecular weight of 31.58 kDa, a theoretical pI of 8.98, and an instability index of 26.10, classifying it as stable. It was predicted to be soluble, non-allergenic, and non-toxic. The refined 3D model showed 93.6% of residues in favored regions of the Ramachandran plot. Docking revealed a strong binding affinity with TLR3 (ΔG = -11.1 kcal/mol, Kd ≈ 1.6×10⁻⁸ M), significantly higher than with TLR4 or TLR7. Immune simulation demonstrated robust humoral and cellular responses, including a rapid increase in IgM after the first injection, isotype switching to IgG1/IgG2, high titers of antibodies, and the establishment of B and T memory cells. High levels of IFN-γ and IL-2 alongside a reduction in regulatory T-cells (Tregs) indicated the induction of a favorable Th1-polarized immune response.
Conclusion: The designed multi-epitope vaccine targeting IL13Rα2 exhibits favorable properties of antigenicity, stability, solubility, and strong interaction with TLR3. In silico analyses suggest it is a promising candidate capable of eliciting potent and specific immune responses against GBM. This construct warrants further validation in experimental and pre-clinical studies to assess its efficacy as a novel immunotherapeutic strategy.