The scavenger receptor class B member 1 (SCARB1), encoded by , is a cell surface receptor for high density lipoproteins, low density lipoproteins (LDL), oxidized LDL (OxLDL), and phosphocholine-containing oxidized phospholipids (PC-OxPLs). is expressed in multiple cell types, including osteoblasts and macrophages. PC-OxPLs, present on OxLDL and apoptotic cells, adversely affect bone metabolism. Overexpression of E06 IgM - a natural antibody that recognizes PC-OxPLs- increases cancellous and cortical bone at 6 months of age in both sexes and protects against age- and high fat diet- induced bone loss, by increasing bone formation. We have reported that is the most abundant scavenger receptor for OxPLs in osteoblastic cells, and osteoblasts derived from knockout mice ( KO) are protected from the pro- apoptotic and anti-differentiating effects of OxLDL. Skeletal analysis of KO mice produced contradictory results, with some studies reporting elevated bone mass and others reporting low bone mass. To clarify if mediates the negative effects of PC-OxPLs in bone, we deleted it in osteoblast lineage cells using Osx1-Cre transgenic mice. Bone mineral density (BMD) measurements and micro-CT analysis of cancellous and cortical bone at 6 months of age did not reveal any differences between mice and their wild-type (WT), Osx1-Cre, or littermate controls. We then investigated whether PC-OxPLs could exert their anti-osteogenic effects via activation of SCARB1 in myeloid cells by deleting in LysM-Cre expressing cells. BMD measurements and micro-CT analysis at 6 months of age did not show any differences between mice and their WT, LysM-Cre, or controls. Based on this evidence, we conclude that Based on this evidence, we conclude that the adverse skeletal effects of PC-OxPLs in adult mice are not mediated by expressed in osteoblast lineage cells or myeloid cells.