Summary
Leukocyte recruitment in the microcirculation is a critical process underlying inflammatory
responses in tissues. The mechanism of recruitment is summarized by the generally
accepted paradigm: selectin-mediated leukocyte rolling, subsequent integrin activation,
followed by integrin-mediated firm adhesion. This simple paradigm may not be able
to explain the leukocyte recruitment mechanisms in some organs including the liver
and brain. Recent studies suggested that these organs have their own leukocyte recruitment
paradigms in acute and even chronic inflammation. The combination of unique hemo-dynamic
patterns and specific structural and functional features of the vessels and endothelium
in liver may dictate and select the specific patterns of leukocyte recruitment in
this organ. In the brain microvasculature, where shears are high and adhesion molecule
expression low, platelets may play an important role as a bridge between the leukocytes
and endothelium.
Keywords
Inflammation - cellular interaction - selectins - integrins - liver - brain