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Updated: Jan 25, 2026

Author Spotlight: A Pseudotype Virus System for Assessing Omicron Subvariants and Neutralizing Antibodies in SARS-CoV-2 Research
Published on: September 8, 2023
VSA-2-, a novel plant-derived adjuvant for SARS-CoV-2 subunit vaccine
Awadalkareem Adam1, Christy Lee2, Madison C Jones2
1Department of Microbiology & Immunology, University of Texas Medical Branch, Galveston, TX 77555, USA; Sealy Institute for Vaccine Sciences, University of Texas Medical Branch, Galveston, TX 77555, USA.
None:
QS-21, a key component of several licensed vaccines is facing limited supply, dose-limiting toxicity and other drawbacks which together limit its broader usage. Development of saponin alternatives to QS-21 that retain its desirable adjuvant activity without its drawbacks is in high need. Incorporating an amide side chain into the more sustainable Momordica saponins (MS) I and II led to the recent discovery of two semisynthetic immunostimulatory adjuvants VSA-1 and VSA-2. Here, we showed that SARS-CoV-2 receptor-binding protein (RBD) adjuvanted with VSA-2 induced high titers of SARS-CoV-2 specific humoral and T helper-1 prone immune responses in mice comparable to that triggered by QS-21-RBD vaccination. Vaccination with VSA-2-RBD provided strong protection against SARS-CoV-2 and variants infection and the virus-induced lung inflammation and pathology similarly as QS-21-RBD vaccination. Overall, our results suggest that VSA-2 adjuvant can potentially complement the clinically proven saponin adjuvant QS-21 in vaccines against infectious diseases.
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Vaccinations
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In a chemical reaction, a relationship exists between the concentration of reactants and the rate at which the reaction proceeds. The study to measure this relationship is known as the kinetics of a chemical reaction. Kinetic studies are used to deduce the rate law of a chemical reaction, which provides information about the species involved during the transition state of the rate-determining step. Thus, kinetic studies help to derive the mechanism of a...
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