Adjuvant potential of Peyssonnelia caulifera extract on the efficacy of an influenza vaccine in a murine model.

Natural adjuvants have recently garnered interest in the field of vaccinology as their immunostimulatory effects. In this study, we aimed to investigate the potential use of Peyssonnelia caulifera (PC), a marine alga, as a natural adjuvant for an inactivated split A/Puerto Rico/8/1934 H1N1 influenza vaccine (sPR8) in a murine model. We administered PC-adjuvanted vaccines to a murine model via intramuscular prime and boost vaccinations, and subsequently analyzed the induced immunological responses, particularly the production of antigen-specific IgG1 and IgG2a antibodies, memory T and B cell responses, and the protective efficacy against a lethal viral infection.

Monophosphoryl lipid A and poly I:C combination enhances immune responses of equine influenza virus vaccine.

Equine influenza is a contagious respiratory disease caused by H3N8 type A influenza virus. Vaccination against equine influenza is conducted regularly; however, infection still occurs globally because of the short immunity duration and suboptimal efficacy of current vaccines. Hence the objective of this study was to investigate whether an adjuvant combination can improve immune responses to equine influenza virus (EIV) vaccines.

Immunostimulatory effects of marine algae extracts on in vitro antigen-presenting cell activation and in vivo immune cell recruitment.

Marine algae are photosynthetic eukaryotic organisms that are widely used as sources of food, cosmetics, and drugs. However, their biological and immunological effects on immune cells have not been fully elucidated. To unravel their immunological activity and broaden their application, we generated antigen-presenting cells (APCs), including dendritic cells (DCs) and macrophages, from mouse bone marrow cells and treated them with six different marine algae extracts (MAEs).

Adjuvant effects of combination monophosphoryl lipid A and poly I:C on antigen-specific immune responses and protective efficacy of influenza vaccines.

Toll-like receptor (TLR) agonists improve vaccine immunogenicity and efficacy, but they are currently unlicensed as adjuvants in influenza vaccines. This study aimed to investigate whether a combination of monophosphoryl lipid A (MPL, a TLR4 agonist) and polyriboinosinic polyribocytidylic acid (poly I:C, a TLR3 agonist) can enhance the protective efficacy of an inactivated A/Puerto Rico/8/1934 (A/PR8) H1N1 influenza vaccine against homologous influenza infection and minimize illness outcomes. Results showed that combination MPL and poly I:C adjuvanted influenza vaccination increased the production of antigen-specific antibodies, decreased the levels of cytokines and cellular infiltrates at the infection sites, and induced significant memory T and B cell responses in mice.

Chronic allergic asthma induces T-cell exhaustion and impairs virus clearance in mice.

Background: Allergic asthma, one of the most common types of asthma, is thought to be highly susceptible to respiratory viral infections; however, its pathological mechanism needs to be elucidated. Recent studies have found impaired T-cell function in asthmatic mice. Therefore, we aimed to investigate the way by which asthma induction affects T-cell exhaustion in the lungs and assess the relationship between T-cell exhaustion and influenza viral infection.