PASC participants had significantly higher frequencies of TNF-α-producing SARS-CoV-2 S- and N-specific CD4+ T cells, (P<0.0001 and P = 0.0003, respectively) (Fig 1J) and significantly increased frequencies of TNF-α-producing CD8+ T cells in response to all three SARS-CoV-2 proteins (Fig 1K) compared to RC participants. Here, CD4 is linked to long COVID-19.