fig1
Figure 1. (1) Neutrophil proteinases are transcribed and packaged early in cellular differentiation in the bone marrow. Cell division later in differentiation divides the preformed packages (azurophil granules) amongst daughter cells and the mature cells are released into the circulation. (2) When the circulating cell senses a chemotactic gradient, it adheres to the endothelium via specific adhesion molecules and transmigrates through endothelial junctions. Granules migrate to the leading edge and the cell releases elastase at the point of transmigration, facilitating movement into the tissues, degrading a connective tissue pathway while leaving enzyme in its wake. (3) The presence of AAT polymers in AATD patients can potentially drive further neutrophil recruitment and local activation, which in the presence of deficiency amplifies local tissue damage, generating chemotactic fragments that add to the chemoattractant signal[31].
