RBD-Protein/Peptide Vaccine UB-612 Elicits Mucosal and Fc-Mediated Antibody Responses against SARS-CoV-2 in Cynomolgus Macaques

Shixia Wang, Farshad Guirakhoo, Sivakumar Periasamy, Valorie Ryan, Jonathan Wiggins, Chandru Subramani, Brett Thibodeaux, Jaya Sahni, Michael Hellerstein, Natalia A. Kuzmina, Alexander Bukreyev, Jean Cosme Dodart, Alexander Rumyantsev

Research output: Contribution to journalArticlepeer-review


Antibodies provide critical protective immunity against COVID-19, and the Fc-mediated effector functions and mucosal antibodies also contribute to the protection. To expand the characterization of humoral immunity stimulated by subunit protein–peptide COVID-19 vaccine UB-612, preclinical studies in non-human primates were undertaken to investigate mucosal secretion and the effector functionality of vaccine-induced antibodies in antibody-dependent monocyte phagocytosis (ADMP) and antibody-dependent NK cell activation (ADNKA) assays. In cynomolgus macaques, UB-612 induced potent serum-neutralizing, RBD-specific IgG binding, ACE2 binding-inhibition antibodies, and antibodies with Fc-mediated effector functions in ADMP and ADNKA assays. Additionally, immunized animals developed mucosal antibodies in bronchoalveolar lavage fluids (BAL). The level of mucosal or serum ADMP and ADNKA antibodies was found to be UB-612 dose-dependent. Our results highlight that the novel subunit UB-612 vaccine is a potent B-cell immunogen inducing polyfunctional antibody responses contributing to anti-viral immunity and vaccine efficacy.

Original languageEnglish (US)
Article number40
Issue number1
StatePublished - Jan 2024
Externally publishedYes


  • ADCP
  • ADMP
  • COVID-19
  • Fc-mediated effector function
  • RBD
  • SARS-CoV-2
  • antibody
  • non-human primates
  • subunit
  • vaccine

ASJC Scopus subject areas

  • Immunology
  • Pharmacology
  • Drug Discovery
  • Infectious Diseases
  • Pharmacology (medical)


Dive into the research topics of 'RBD-Protein/Peptide Vaccine UB-612 Elicits Mucosal and Fc-Mediated Antibody Responses against SARS-CoV-2 in Cynomolgus Macaques'. Together they form a unique fingerprint.

Cite this