Chapter 11 Interaction of pulmonary endothelial cells with blood elements

Publisher Summary This chapter focuses on the interaction of leukocytes and plasma proteins with endothelial cells in the lung. During pulmonary inflammation, endothelial and blood cells respond to the released mediators, thereby resulting in enhanced interaction between endothelial cells and blood cells, including leukocytes. This chapter discusses the interaction of endothelial cells with blood elements, with an emphasis on the interaction of endothelial cells with neutrophils—the most numerous types of polymorphonuclear leukocytes—during acute pulmonary inflammation. In healthy lungs, the capillary blood contains a higher concentration of neutrophils than the blood in large vessels. This marginated pool in the pulmonary capillaries exists even in the absence of an inflammatory stimulus and is due primarily to the anatomical characteristics of pulmonary capillaries and the biomechanical properties of neutrophils. In addition, neutrophil emigration in response to an acute inflammatory stimulus occurs primarily in the pulmonary capillaries. This process involves the sequestration of neutrophils in the pulmonary capillaries, adhesion of neutrophils to the pulmonary capillaries, transmigration of neutrophils across endothelium, and migration of neutrophils through extracellular matrix and across alveolar epithelial cells into the alveolar space.