Fig. 2

a–d Percentage of PD-L1⁺ NK cells in the derivation cohort of patients with sepsis. a Flow dot plots of the percentage of comparison PD-L1⁺ NK cells between non-survivor and survivors of sepsis patients. b Dot plots showing the percentage of PD-L1⁺ NK cells of sepsis patients to ascertain the statistical differences between the non-survivor and the survivor groups. The samples had a significantly higher proportion of PD-L1⁺ (16.77 (10.20–48.42) vs. 11.84 (2.01–26.98), p = 0.013) in NK cells in non-survivors (n = 30) as compared to survivors (n = 84). c Dot plots showing the percentage of PD-L1⁺ NK cells of sepsis patients to ascertain the statistical differences between the bloodstream infection and non-bloodstream infection group. The samples had a significantly higher proportion of PD-L1⁺ [37.77 (11.83–61.98) vs. 12.55 (4.99–26.44), p = 0.036] in the NK cells in the bloodstream infection (n = 9) as compared to the non-bloodstream infection group (n = 105). d Dot plots showing the percentage of PD-L1⁺ NK cells of sepsis patients to ascertain the statistical differences between patients with and without septic shock. No significant difference was detected in the percentage of PD-L1⁺ NK cells between the two groups