reticuloendothelial system (RES), a functional rather than anatomical system of the body involved primarily in defense against infection and in disposal of the products of the breakdown of cells. It is made up of macrophages; the Kupffer cells of the liver; and the reticulum cells of the lungs, bone marrow, spleen, and lymph nodes. Disorders of this system include eosinophilic granuloma, Gaucher’s disease, Hand’s disease, and Niemann-Pick disease.
