Macrophage Scavenger receptor types I and II (MSR1, and also known as SCARA1) are members of the class A macrophage scavenger receptor family. These proteins bind large quantities of modified lipoproteins and promote endocytosis. Upregulation of MSR1 in infiltrating myeloid cells may mediate clearance of specific damage signals in response to tissue injury, including ischemic stroke. MSR1 germ line mutations are also associated with increased prostate cancer susceptibility in some patient cohorts. MSR1 is observed to be upregulated in differentiated THP-1 cells.
