The recognition and removal of apoptotic cells is mediatedby a variety of molecules, including receptors on the phagocyte surface and solublebridging proteins such as MFG-E8, thrombospondin-1, and protein S. Both an increase inthe number of apoptotic cells and defective efferocytosis are involved in thepathogenesis of COPD (8-10). The gene discussed is THBS1; the disease is chronic obstructive pulmonary disease.