LXR Alpha, also known as Liver X receptor Alpha is a 50KDa protein that belongs to the nuclear hormone receptor family located in the nucleus. It is specifically expressed in the liver, kidney and intestine; however it has also been found in the spleen, macrophages and the adrenals. All of these tissues play an important role in lipid metabolism. The primary role of LXR Alpha is to maintain cholesterol homeostasis in macrophages by regulating the genes involved in this.