HYBRID EVENT: You can participate in person at Baltimore, Maryland, USA or Virtually from your home or work.
Alex Zhu, Speaker at Immunology Conferences
University of Duisburg-Essen, United States
Title : Robust antibody-mediated protection against SARS-CoV-2 induced by NVX-CoV2373 subunit vaccine adjuvanted with matrix-M


Recently approved vaccines have shown remarkable efficacy in limiting SARS-CoV-2-associated disease. However, with the variety of vaccines, immunization strategies, and waning antibody titers, defining the correlates of immunity across a spectrum of antibody titers is urgently required. Thus, we profiled the humoral immune response in a cohort of non-human primates immunized with an adjuvanted recombinant SARS-CoV-2 spike glycoprotein (NVX-CoV2373) at two doses, administered as a single- or two-dose regimen. Both antigen dose and boosting significantly altered neutralization titers and Fc-effector profiles, driving unique vaccine-induced antibody fingerprints. Combined differences in antibody effector functions and neutralization were associated with distinct levels of protection in the upper and lower respiratory tract. Moreover, NVX-CoV2373 elicited antibodies that functionally targeted emerging SARS-CoV-2 variants. Collectively, the data presented here suggest that a single dose may prevent disease via combined Fc/Fab functions but that two doses may be essential to block further transmission of SARS-CoV-2 and emerging variants.

Audience Take Away:

  • The FDA Emergency Use Authorized NVX-CoV2373 subunit vaccine elicits neutralizing and Fc-effector functional antibodies
  • The NVX-CoV2373 vaccine protects against upper and lower respiratory tract infection in non-human primates by eliciting neutralizing antibodies and Fc-mediated effector functions
  • Vaccine-induced antibody responses in humans exhibit altered Fc-receptor binding to SARS-CoV-2 variants
  • Listeners will gain an understanding of a suite of assays developed for the quantification of antibody Fc-mediated recruitment of innate immune functions.


Alex has a background in immunology and works on prophylactic vaccines aimed towards minimizing the global toll of infectious diseases. He is particularly focused on viruses with pandemic potential and shifted his work towards SARS-CoV-2 during the pandemic. He is interested in exploring the utilization of adjuvants to further enhance the immunogenicity and efficacy of vaccines.