Differential efficacy of TLRL adjuvants in COVID-19 protein subunit vaccines

Authors

• CM Farrell
• OD Ermolaeva
• CL Wallin
• TD Murphy

Abstract

Although COVID-19 may no longer be a Public Health Emergency, its effects are still being felt both here and throughout the world. Universal access to cheap, transportable, and effective vaccines is critical to ensuring public health and safety. Protein subunit vaccines are safer and easier to transport than live virus or mRNA vaccines, but they are less immunogenic. To create an effective protein subunit vaccine, immunostimulatory substances known as adjuvants must be added. Adjuvants both stimulate and shape the immune response, allowing an otherwise weakly immunogenic protein to provide full protective immunity. This research examines the efficacy of toll-like receptor ligands (TLRLs) as adjuvants in an S1 COVID-19 protein subunit vaccine. Vaccines containing these adjuvants have previously been shown to induce a stronger immune response than the protein alone. Healthy mice were given an S1 protein vaccine which contained various combinations of TLRL adjuvants. The immune response was characterized at each dose and at the end of the study to track changes over time. Humoral immunity was characterized by determining the blood concentration of anti-S1 antibodies produced in response to the vaccine, as well as the neutralizing capability if these antibodies. Cellular immunity was characterized using flow cytometry to follow changes in the T cell populations following vaccination. These data highlight the potential of TLRL adjuvant vaccines and demonstrate the need for future investigations into their use for current and emerging viral diseases.

Scientific Focus Area: Immunology

This page was last updated on Monday, September 25, 2023