Objective: In these days, the importance of vaccines as a countermeasure against the COVID-19 pandemic has been highlighted, and a new method of evaluating the safety and efficacy of vaccines using bioinformatics (reverse vaccinology) has been proposed. In this study, we evaluated the efficacy of LC16m8, an attenuated cell culture vaccine against smallpox, by using protein array.
Methods: Serum samples were collected from 388 subjects before and 30 days after LC16m8 inoculation, and protein array analysis was performed. For plaque reduction neutralizing (PRN) titer, the vaccinia virus NYCBH strain was used as the challenge virus. This study was approved by the Clinical Research Review Committee of SDF Central Hospital.
Results: In the primary vaccinees(N=82), the differentially recognized antigens among the pre- and post- vaccination included A10, A11, A13, A27, A33, D8, D13, H3, I1, and WR148. In re-vaccinees(N=306), the most reactive antigens included A27, D8, D13, H3, I1 and WR148. In anti-vaccinia immunity, multiple antibodies are thought to be involved in neutralization. Upon vaccination with LC16m8, a weak correlation was observed for anti-D8 antibodies in the primary vaccinees (r=0.3779, P<0.05). In re-vaccinees, anti-WR149, -H3, -A27, -A14, and -D8 antibodies displayed weak correlations with PRN titer. A comparison of the mean signal intensities between the high (≥32) and low (<32) PRN titer groups showed that, among the intracellular mature virion antigens, antibodies against H3, D8, A13, A14, WR148, and A27 were significantly higher in the high PRN titer group than in low PRN titer group both in the naive　and revaccinated individuals, suggesting the importance of these antibodies in the human immune response upon vaccination.