CD4 and influenza: Further, using only one or two markers for each cell population, four of the 11 cell populations differentiating between the severely and moderately ill patients were successfully gated, suggesting that these markers may be useful as potential biomarkers for high-throughput screening of severe influenza: CD4+ T cells (CD4+; p = 0.04), MAIT (TCRVa7.2+; p = 0.0003), NK cells (CD56+CD3−, p = 0.02), and activated monocytes (CD169+CD3−, p = 0.0017).