COVID-19 is a global pandemic caused by the SARS-CoV-2 coronavirus. T cells play a key role in the adaptive antiviral immune response by killing infected cells and facilitating the selection of virus-specific antibodies. However, neither the dynamics and cross-reactivity of the SARS-CoV-2-specific T-cell response nor the diversity of resulting immune memory is well understood. In this study, we use longitudinal high-throughput T-cell receptor (TCR) sequencing to track changes in the T-cell repertoire following two mild cases of COVID-19. In both donors, we identified CD4 + and CD8 + T-cell clones with transient clonal expansion after infection. We describe characteristic motifs in TCR sequences of COVID-19-reactive clones and show preferential occurrence of these motifs in publicly available large dataset of repertoires from COVID-19 patients. We show that in both donors, the majority of infection-reactive clonotypes acquire memory phenotypes. Certain T-cell clones were detected in the memory fraction at the pre-infection time point, suggesting participation of pre-existing cross-reactive memory T cells in the immune response to SARS-CoV-2.
【저자키워드】 COVID-19, SARS-CoV-2, Human, TCR, RepSeq, 【초록키워드】 antibodies, coronavirus, immune response, adaptive, T cells, T-cell Response, Sequencing, Infection, SARS-CoV-2 coronavirus, CD4, CD8, memory, global pandemic, cross-reactivity, T cell, Participation, memory T cells, dataset, immune memory, T-cell receptor, donors, T-cell, characteristic, memory T cell, COVID-19 patients, Diversity, cross-reactive, clonal expansion, antiviral immune response, Phenotypes, infected cells, fraction, infected cell, virus-specific antibodies, clone, motif, memory T, TCR sequences, killing, Occurrence, resulting, caused, majority, changes in, mild case, TCR sequence, the SARS-CoV-2, 【제목키워드】 COVID-19 infection, Mild, T-cell, longitudinal, memory formation, reveal,