PDS Biotechnology’s investigational infectious disease immune activating platform, Infectimune, has shown promising results in boosting CD4 T cell responses to influenza vaccines, suggesting that Infectimune-based vaccines could provide durable protection against seasonal flu and potentially emerging pandemic flu, according to a preclinical study published in Viruses.
The research, performed in the laboratory of preeminent CD4 T cell researcher Andrea Sant, PhD, at the University of Rochester Center for Vaccine Biology and Immunology, studied Infectimune and demonstrated the technology’s potency in eliciting CD4 T cells.
The studies focused on comparing Infectimune-induced immune responses following primary vaccination against influenza with immune responses induced by leading vaccine adjuvants. This publication follows a recent article in Viruses highlighting the ability of Infectimune to generate a broad immune response against viruses, including SARS-CoV-2 and multiple strains of influenza.
The paper, titled “R-DOTAP cationic lipid nanoparticles outperform squalene-based adjuvant systems in elicitation of CD4 T cells after recombinant influenza hemagglutinin vaccination,” reported findings investigating the ability of Infectimune (R-DOTAP) to promote CD4 T cell responses to vaccination with recombinant influenza protein.
Infectimune was compared to AddaVax, which is analogous to commercial adjuvant MF59, and AddaVax combined with CpG, a commercial adjuvant, using HA-B as the influenza vaccine antigen. Results from the study concluded that Infectimune dramatically enhanced CD4 T cell responses to recombinant HA-B proteins relative to AddaVax and AddaVax plus CpG.
Further, the Infectimune-elicited CD4 T cells displayed abundant interferon-gamma and interleukin-2 production that are critical for protective immunity. CD4 T cells are documented to present multiple functions, including CD8 T cell expansion and antibody responses, as well as direct anti-viral effects and potentiation of antigen-presenting function to enhance protection against viral infection.
“Influenza remains challenging due to low immune responses, especially in the elderly. Thus, there is a significant opportunity to develop a flu vaccine that induces broadly protective responses to influenza,” says Gregory Conn, PhD, PDS Biotechnology chief scientific officer, in a press release.
Sant, the senior author of the paper, states in the press release, “These results showing the potency of R-DOTAP to promote epitope-specific, cytokine-inducing CD4 T cells against a recombinant influenza antigen are exceptionally promising.”