Therefore, in addition to determining the roles of other IgM-like innate immune proteins such as lung surfactant protein D [1], [2], [43], [50], [51], the complete understanding of IgM-mediated apoptotic particle clearance is essential to effectively treat and control diseases of biological particle accumulation, autoimmunity (e.g., SLE or rheumatoid arthritis), infection and inflammation. Here, SFTPD is linked to systemic lupus erythematosus.