CD8A and long COVID-19: We identified significant positive correlations between S, N and M combined, S-specific and N-specific frequencies of TNF-α-producing SARS-CoV-2-specific CD8+ (r = 0.55; P = 0.0064, r = 0.47; P = 0.019 and r = 0.42; P = 0.032, respectively) T cells and plasma IL-6 in PASC participants (Fig 4C).