A self-transcribing and replicating RNA (STARR) based vaccine (LUNAR®-COV19) has been developed to prevent SARS-CoV-2 infection. The vaccine encodes an alphavirus-based replicon and the SARS-CoV-2 full length spike glycoprotein. Translation of the replicon produces a replicase complex that amplifies and prolong SARS-CoV-2 spike glycoprotein expression. A single prime vaccination in mice led to robust antibody responses, with neutralizing antibody titers increasing up to day 60. Activation of cell mediated immunity produced a strong viral antigen specific CD8 T lymphocyte response. Assaying for intracellular cytokine staining for IFN-γ and IL-4 positive CD4 T helper lymphocytes as well as anti-spike glycoprotein IgG2a/IgG1 ratios supported a strong Th1 dominant immune response. Finally, single LUNAR-COV19 vaccination at both 2 μg and 10 μg doses completely protected human ACE2 transgenic mice from both mortality and even measurable infection following wild-type SARS-CoV-2 challenge. Our findings collectively suggest the potential of LUNAR-COV19 as a single dose vaccine.Copyright © 2021. Published by Elsevier Inc.
About The Expert
Ruklanthi de Alwis
Esther S Gan
Shiwei Chen
Yan Shan Leong
Hwee Cheng Tan
Summer L Zhang
Clement Yau
Jenny G H Low
Shirin Kalimuddin
Daiki Matsuda
Elizabeth C Allen
Paula Hartman
Jenny Park
Maher Alayyoubi
Hari Bhaskaran
Adrian Dukanovic
Yanjie Bao
Brenda Clemente
Jerel Vega
Scott Roberts
Jose A Gonzalez
Marciano Sablad
Rodrigo Yelin
Wendy Taylor
Kiyoshi Tachikawa
Suezanne Parker
Priya Karmali
Jared Davis
Sean M Sullivan
Steve G Hughes
Pad Chivukula
Eng Eong Ooi
References
PubMed