protsessi käigus, mida kutsutakse ka diapedeesiks, lahkuvad neutrofiilid vereringest ning tungivad läbi endoteelirakkude kihi, et jõuda allolevatesse kahjustatud või patogeenide poolt nakatunud kudedesse, The cytoskeletons of the leukocytes are reorganised in such a way that the leukocytes are spread out over the endothelial cells. In this form, leukocytes extend pseudopodia and pass through gaps between endothelial cells. Transmigration of the leukocyte occurs as PECAM proteins, found on the leukocyte and endothelial cell surfaces, interact and effectively pull the cell through the endothelium.