Assessment of Adaptive Immune Response Against Influenza Using Synthetic Peptides

Objective: This study evaluated a method for assessing the immunogenicity of synthetic peptides as a potential clinical diagnostic for cellular immune responses to influenza virus. Two 9-mer peptides corresponding to epitopes from the 2023-2024 Northern Hemisphere vaccine strains were used: a 432–440 aa fragment of influenza A hemagglutinin (Phe–Leu–Asp–Ile–Trp–Thr–Tyr–Asn–Ala) and a 454–462 aa fragment of influenza B neuraminidase (Leu–Leu–Trp–Asp–Thr–Val–Thr–Gly–Val). Methods: The peptides were synthesized using classical methods of peptide chemisty, employing carbodiimide condensation with activated amino acid esters. Fifty five volunteers (aged 20–26) too part in the clinical study. Gamma interferon (IFN-γ) production was measured by the ELISA assay. Results and Discussion: No statistically significant differences in IFN-γ levels were observed across any pairwise comparisons. Conclusions: The diagnostic method requires further optimization before it can be reliably used for clinical assessment of cellular immune response to influenza A virus.