Abstract 49: Myeloid Cell Specific ABCA1 Deletion Does Not Significantly Accelerate Atherogenesis in LDL Receptor Knockout Mice

ATP binding cassette transporter A1 (ABCA1) functions as a cellular cholesterol exporter. Macrophage ABCA1 expression is important in reducing cellular cholesterol content and inflammatory response. Bone marrow (BM) transplantation studies suggest that leukocyte ABCA1 protects against atherosclerosis development. However, the in vivo effect of macrophage ABCA1 in atherogenesis is not fully understood due to the presence in BM of other leukocyte populations. Myeloid[[Unable to Display Character: ‐]]Specific ABCA1 Knockout (MSKO) mice in the LDL receptor knockout (LDLrKO) C57BL/6 background were developed to address this question. MSKO/LDLrKO (DKO) and LDLrKO (SKO) mice were fed chow or an atherogenic diet for 10-24wk to examine early to advanced stages of atherosclerosis. Basal (i.e. chow) plasma lipid levels were similar between genotypes, but relative to SKO mice, DKO mice had reduced plasma apoB[[Unable to Display Character: ‐]]containing lipoprotein (apoB Lp) levels throughout the diet-indu...