Expression of the LXRα protein in human atherosclerotic lesions

Objective - Liver X - activated receptor alpha ( LXR alpha) regulates multiple genes controlling cholesterol metabolism and transport. To clarify its role in atherogenesis, we established a monoclonal antibody recognizing native human LXRalpha protein and studied the expression pattern in human atherosclerotic lesions. Methods and Results - A novel monoclonal antibody PPZ0412 was raised against the ligand-binding domain of LXRalpha, which can be used for immunostaining of human LXRalpha protein. LXRalpha protein was detected in the nucleus of macrophages in the liver, spleen, or lung and also in hepatocytes and adipocytes. In atherosclerotic lesions, the LXRalpha protein was detected in macrophages positive for scavenger receptor class A and/or CD68. Conclusions - In the human body, the LXRalpha protein is highly expressed in macrophage lineage cells and foam cells in atherosclerotic lesions and is identified as a target for intervention in atherosclerotic disease.