First computational design using lambda-superstrings and in vivo validation of SARS-CoV-2 vaccine

Luis Martínez1,2, Iker Malaina3,4, David Salcines-Cuevas5

  • 1Department of Mathematics, Faculty of Science and Technology, University of the Basque Country, UPV/EHU, 48940, Leioa, Spain. luis.martinez@ehu.eus.

Scientific Reports
|April 20, 2022
PubMed

Insights

Researchers developed a novel peptide vaccine candidate for COVID-19 using lambda-superstring optimization. This dendritic cell vaccine, targeting the SARS-CoV-2 Spike protein, demonstrated significant immunogenicity and induced a protective Th1-Th17 cytokine profile in human trials.

Area of Science:

  • Immunology
  • Vaccinology
  • Computational Biology

Background:

  • Coronavirus disease 2019 (COVID-19) remains a global health threat, necessitating continuous vaccine development despite existing advancements.
  • Uncertainty regarding the long-term efficacy and duration of immunity from current severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines underscores the need for alternative vaccine strategies.
  • Peptide-based vaccines offer a promising avenue for developing new vaccines against SARS-CoV-2.

Purpose of the Study:

  • To computationally design novel peptide vaccine candidates against SARS-CoV-2 using lambda-superstring optimization.
  • To evaluate the immunogenicity, immune response type, and cytokine profile of a dendritic cell (DC) vaccine vector loaded with a SARS-CoV-2 Spike protein peptide (DC-CoVPSA).
  • To establish proof of concept for the lambda-superstring optimization technique and the DC-CoVPSA vaccine in human subjects.

Main Methods:

  • Computational design of monopeptide and multipeptide vaccine candidates using lambda-superstring optimization.
  • Synthesis of a 22-amino acid peptide (CoVPSA) from the SARS-CoV-2 Spike protein NTD domain and its loading onto a DC vaccine vector.
  • In vivo immunogenicity testing in animal models and ex vivo analysis of immune responses and cytokine profiles (Th1-Th17).
  • Proof of concept human trials involving asymptomatic COVID-19 patients, vaccinated volunteers, and control donors, with current RNA-vaccine epitopes as positive control.

Main Results:

  • The CoVPSA peptide demonstrated significant immunogenicity in vivo when delivered via a DC vaccine vector.
  • The DC-CoVPSA vaccine elicited robust cellular and humoral immune responses, characterized by a predominant Th1-Th17 cytokine profile indicative of effective antiviral activity.
  • The lambda-superstring optimization technique was validated, and proof of concept was successfully established in human subjects.

Conclusions:

  • The lambda-superstring optimization technique is a valid and effective method for identifying optimal epitopes from the SARS-CoV-2 Spike protein for peptide-based vaccine development.
  • The developed DC vaccine vector (DC-CoVPSA) represents a promising candidate for a peptide-based vaccine against COVID-19.
  • This approach is adaptable for various vector platforms, offering flexibility in future vaccine design against SARS-CoV-2.