Natural killer cell dysfunction is associated with colorectal cancer with severe COVID-19

Figure 1 Natural killer and natural killer T cells gating strategy from representative histogram of flow cytometric analysis. Graphs represented from left to right: Leukocyte population gating based on Side Scatter and Forward Scatter dot plot; leukocytes gating through Side Scatter and CD45; upper left quadrant represents CD3^-CD16/CD56⁺ natural killer (NK) cell population. upper right quadrant represents CD3⁺CD16/CD56⁺ NKT cell population.

Figure 2 Comparison of numbers and percentages of peripheral natural killer and natural killer T cells between colorectal cancer and colorectal cancer with severe the coronavirus disease 2019 patients. A: Representative histogram in peripheral blood of colorectal cancer (CRC) and CRC with severe the coronavirus disease 2019 (CRC⁺) patients; B: Comparison of natural killer (NK) and NKT cell numbers between CRC and CRC⁺ patients; C: Comparison of NK and NKT cell percentages between CRC and CRC⁺ patients. ^aP < 0.05 vs CRC⁺via Student's t test; ^bP < 0.05 vs CRC⁺via Mann-Whitney U test; CRC: Colorectal cancer; CRC⁺: Colorectal cancer with severe the coronavirus disease 2019; NK: Natural killer.

Figure 3 Comparison of natural killer cell cytotoxic activity and natural killer cytotoxic factor activity between colorectal cancer and colorectal cancer with severe the coronavirus disease 2019 patients. ^aP < 0.05 vs colorectal cancer with severe the coronavirus disease 2019 (CRC⁺) via Student's t test; ^bP < 0.01 vs CRC⁺via Mann-Whitney U test; CRC: Colorectal cancer; CRC⁺: Colorectal cancer with severe the coronavirus disease 2019; NKCA: Natural killer cell cytotoxic activity; NKCF: Natural killer cytotoxic factor.

Figure 4 The correlation analysis between natural killer cells and natural killer cell cytotoxicity in colorectal cancer with severe the coronavirus disease 2019 patients. NK: Natural killer; NKCA: Natural killer cell cytotoxic activity; NKCF: Natural killer cytotoxic factor.

Figure 5 Receiver operating characteristic curve analysis of natural killer cells and natural killer cell cytotoxicity between colorectal cancer and colorectal cancer with severe the coronavirus disease 2019 patients. NK: Natural killer; NKCA: Natural killer cell cytotoxic activity; NKCF: Natural killer cytotoxic factor.