Table 1.

Relevance of human and mouse CD11a/CD18 and CD11b/CD18 in neutrophil function.

	Human CD11a/CD18	Human CD11b/CD18	Mouse CD11a/CD18	Mouse CD11b/CD18
Adhesion/Crawling	Initial adhesion of intermediate-avidity to endothelium following selectin-mediated rolling. After firm CD11b/CD18-mediated adhesion, a role in crawling over the endothelium (131)	Suggested to become fully active after CD11a/CD18. Pivotal in firm adhesion to the endothelial cell wall (131)	Most pivotal of the CD11/CD18 isoforms in mice, KO results in severe adhesion defects despite presence of CD11b/CD18 (249)	More redundant in mice, but adhesion and migration is affected in its absence (249).
Antibody derived cellular cytotoxicity (ADCC)	N/A	Activated via Fcγ-receptors, involved in downstream signaling (216).	N/A	N/A
Chemotaxis/spreading (Two-dimensional)	Turnover of CD11a/CD18 during chemotaxis (166).	Increased avidity of CD11b/CD18 at cell-contact sites (250).	CD11a/CD18 seems more important compared to CD11b/CD18 in mice (176).	N/A
Phagocytosis/ROS production	No role described for CD11a/CD18 (251).	Binding of pathogens in a lectin-like way or once opsonized with iC3b and C4b (189). Recruits Fcγ-receptors for downstream signaling (196).	N/A	Binding of complement-opsonized zymosan. Recruits Fcγ-receptors for downstream signaling (221).

Summary list of human or murine studies regarding β2 integrin activation, inside-out or outside-in signaling during neutrophil effector function.