Figure 4. Correlation of frequencies of CD14+HLA-DRlo/neg MDSCs and lymphocyte subsets in 18 COVID-19 patients. Frequencies of CD14+HLA-DRlo/neg MDSCs showed negative correlations with CD3+T count (A), CD3+CD4+T count (B), CD3+CD8+T count (C), CD3-(CD16+CD56+)NK count (D) and CD3-(CD16+CD56+)NK percentage (E). CD14+HLA-DRlo/neg MDSCs percentages were positively correlated with CD3-CD19+B cell frequencies (F). Abbreviations: MDSCs, myeloid-derived suppressor cells.