Fig. 6: TLR4 deficiency alleviates cholesterol efflux suppression in septic macrophages.

A The AUC scores for lipid metabolism and cholesterol efflux from scRNA-seq analysis across the four groups. B The expression level of Abca1 from scRNA-seq analysis across the four groups. C Representative immunofluorescence images of lung tissue stained with F4/80 (green) and ABCA1 (red) in the four groups. The bar graph quantifies the number of F4/80⁺ ABCA1⁺ macrophages per mm² (n = 3). Scale bar, 20 μm. D Immunofluorescence detection and quantification of ABCA1 expression in macrophages from BALF of mice (n = 5). Scale bar, 20 μm. E Bar graph showing cholesterol efflux (%) in macrophages isolated from BALF and incubated with a cholesterol acceptor (serum) for 6 hours in vitro. F–I Bar graphs showing concentrations of pro-inflammatory cytokines (IL-1α, IL-1β, IL-6, and TNF-α) in macrophage supernatants after 6 hours of in vitro culture without any additional treatment. Data are represented as mean ± SD or median (interquartile range), *P < 0.05, **P < 0.01, ***P < 0.001.