Figure 1

LPS exposure causes an activated/dysfunctional ECs phenotype (I). ECs exposed to 1 μg/ml LPS for 48 h show open IEJs, (a, b), increased accumulation of actin filaments at cell periphery (c, arrows), significant increase in the number of Weibel-Palade (wp) bodies (d) and Golgi (f, circled areas). An enlarged and widespread endoplasmic reticulum network and the presence of a dilated tubular system are shown in e; frequently, increase number of lysosomal (lys) units is observed (a, d, f). Panel g shows a segment of cultured lung microvascular ECs comprising increased number of mitochondrial units (m), most of them with abnormal morphology. Note also the close association between ER and mitochondria. Frequently, mitochondria undergo a fission process (g1). Bars: 100 nm (a, b, d, e, f, g); 50 nm (c);