Expression of CD16/32 on the cell surface in the ET and LPS groups. The cell surface marker CD16/32 was analyzed by flow cytometry. (A) BLANK-P1: Isotype staining; (B) N-P1: No staining; (C) ET-P1: ET group following treatment with high-dose LPS for 4 h; (D) SE-P1: LPS group following treatment with high-dose LPS for 4 h; (E) ET-P1: ET group following treatment with high-dose LPS for 24 h; (F) SE-P1: LPS group following treatment with high-dose LPS for 24 h. The positive rate of CD16/32 in the ET group (75.33%) was higher compared with the LPS group (49.69%) following stimulation with high-dose LPS for 4 h (P<0.05). Following treatment for 24 h, the positive rate of CD16/32 (79.07%) in the ET group was lower when compared with the LPS group (94.27%; P<0.05). LPS, lipopolysaccharide; ET, endotoxin tolerance; CD, cluster of differentiation; FITC, fluorescein isothiocyanate; N, no staining; ET, endotoxin tolerance; SE, sepsis.