Establishment and Recall of SARS-CoV-2 Spike Epitope-Specific CD4⁺ T Cell Memory

Using a novel HLA-DRB1*15:01/S₇₅₁ tetramer to track spike-specific CD4⁺ T cells, scientists showed that primary infection or vaccination induced robust S₇₅₁-specific CXCR5⁻ and cT_FH cell memory responses.