what is the reticuloendothelial system
Reticuloendothelial System (RES). a system of cells of mesenchymal origin in vertebrate animals and in man that can be converted to actively mobile phagocytic cells (macrophages).I.I.eticuloendothelial System (RES). a system of cells of mesenchymal origin in vertebrate animals and in man that can be converted to actively mobile phagocytic cells (macrophages). I.I.