Extracellular matrices regulate extravasation journey of leukocytes and inflammatory tissue fate

Leukocyte extravasation across the blood endothelium to inflamed tissues is a crucial defence mechanism against invading pathogens. After elimination of pathogen in the tissue, inflammation needs to be resolved back to steady-state. This cascade comprises of several stages: transmigration through the endothelium and the underlying basement membrane, intra-tissue leukocyte activity, and tissue resolution. In each stage, extracellular matrix proteins in the vascular basement membrane and in tissues regulate a multitude of endothelial and leukocyte functions essential to completion of the cascade, either as a collective force-permissive structure or through signalling by individual matrix proteins. This review will focus on how these extracellular matrices regulate the extravasation journey of leukocytes to illustrate their tight functional inter-dependence with profound impacts on the ultimate post-inflammation tissue fate.