Immunological memory to SARS-CoV-2 assessed for up to 8 months after infection

Dan, Jennifer M.; Mateus, Jose; Kato, Yu; Hastie, Kathryn M.; Yu, Esther Dawen; Faliti, Caterina E.; Grifoni, Alba; Ramirez, Sydney I.; Haupt, Sonya; Frazier, April; Nakao, Catherine; Rayaprolu, Vamseedhar; Rawlings, Stephen A.; Peters, Bjoern; Krammer, Florian; Simon, Viviana; Saphire, Erica Ollmann; Smith, Davey M.; Weiskopf, Daniela; Sette, Alessandro; Crotty, Shane

Understanding immune memory to SARS-CoV-2 is critical for improving diagnostics and vaccines, and for assessing the likely future course of the COVID-19 pandemic. We analyzed multiple compartments of circulating immune memory to SARS-CoV-2 in 254 samples from 188 COVID-19 cases, including 43 samples at ≥ 6 months post-infection. IgG to the Spike protein was relatively stable over 6+ months. Spike-specific memory B cells were more abundant at 6 months than at 1 month post symptom onset. SARS-CoV-2-specific CD4(+) T cells and CD8(+) T cells declined with a half-life of 3-5 months. By studying antibody, memory B cell, CD4(+) T cell, and CD8(+) T cell memory to SARS-CoV-2 in an integrated manner, we observed that each component of SARS-CoV-2 immune memory exhibited distinct kinetics.