Cell-mediated immune response by ELISpot to ancestral Wuhan strain
All participants, except one, had negative responses at baseline. One participant had a low ELISpot response to S-protein (24 SFU). 2 weeks after the second dose, all participants across the four regimens had significant increases in IFN-γ response against S-protein. The highest GM SFU for S-protein 2 weeks after the second dose was observed in Group 2 (441.34; 95% CI 271.10, 718.47), followed by Group 1 (373.80; 95% CI 246.12, 567.72), Group 4 (224.99; 95% CI 136.63, 370.50), and Group 3 (85.88; 95% CI 42.22, 174.70) (see SARS-CoV-2 antigen-specific T-cell responses by ELISpot at baseline and 2 weeks after the second dose following accelerated regimens of fractional, ID administration. 