Real-time imaging reveals endothelium-mediated leukocyte retention in LPS-treated lung microvessels

►Focal LPS delivery into microvessels of isolated lungs by microcatheter. ►Infused fluorescently-labeled autologous leukocytes into LPS-treated vessels. ►Intravital microscopy of leukocyte transit through lung microvessels. ►LPS increased leukocyte retention in pulmonary venules and capillaries. ►Endothelial TLR4 and ICAM-1 inhibition blocked leukocyte retention.