Exploring the adjuvant potential of Peyssonnelia caulifera extract on the efficacy of influenza vaccine in a mice model

Abstract

Exploring the adjuvant potential of Peyssonnelia caulifera extract on the efficacy of influenza vaccine in a mice model Ho Thi Len Department of Interdisciplinary Graduate Program in Advanced Convergence Technology and Science Graduate School Jeju National University Adjuvants sourced from natural origins have attracted significant attention for their immune-boosting properties within vaccine development. This study focused on assessing the effectiveness of Peyssonnelia caulifera (PC), a species of marine algae, in serving as a natural adjuvant candidate for the inactivated split A/Puerto Rico/8/1934 H1N1 influenza vaccine (sPR8). PC effectively stimulates antigen- presenting cells (APCs), leading to increased pro-inflammatory cytokine production and T cell activation in vitro. Furthermore, vaccines adjuvanted with PC elicited higher levels of antigen-specific IgG1 and IgG2a antibodies than traditional alum-adjuvanted vaccines, indicating a robust humoral response. Notably, the PC- adjuvanted vaccine was superior in inducing a potent T helper type 1 (Th1) cellular immunity, as reflected in the elevated IgG2a antibody levels. In addition, vaccination with PC significantly enhanced the generation of memory B and T cell populations, providing a foundation for sustained immune protection. In vivo protection assays revealed a decrease in viral load and inflammatory responses in PC-adjuvanted vaccinated mice upon viral challenge, highlighting the adjuvant's effectiveness in triggering a strong immune response. These findings offer insights into the immune-modulating effects of natural adjuvants and support the enhancement of vaccination strategies against infectious diseases. Keywords: Peyssonnelia caulifera (PC), natural adjuvant, influenza vaccine, Th1 immunity.