Leukocyte integrin Mac-1 (CD11b/CD18, α_Mβ₂, CR3) acts as a functional receptor for platelet factor 4.

ABSTRACT: Platelet factor 4 (PF4) is one of the most abundant cationic proteins secreted from α-granules of activated platelets. Based on its structure, PF4 was assigned to the CXC family of chemokines and has been shown to have numerous effects on myeloid leukocytes. However, the receptor for PF4 remains unknown. Here, we demonstrate that PF4 induces leukocyte responses through the integrin Mac-1 (α_Mβ₂, CD11b/CD18). Human neutrophils, monocytes, U937 monocytic and HEK293 cells expressing Mac-1 strongly adhered to immobilized PF4 in a concentration-dependent manner. The cell adhesion was partially blocked by anti-Mac-1 mAb and inhibition was enhanced when anti-Mac-1 antibodies were combined with glycosaminoglycans, suggesting that cell-surface proteoglycans act cooperatively wi

SUBMITTER: Lishko VK 

PROVIDER: S-EPMC5936813 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature