Our research is focused on the regulation of the complement system in health and disease. Complement is crucial part of innate immunity and thus protects host from infections and contributes to removal of dying cells. We study involvement of complement in pathology of rheumatic and inflammatory diseases as well as several types of cancer. Further, we investigate strategies developed by bacterial pathogens in order to avoid killing by complement, which results in infections. Our main focus is on various complement inhibitors such as C4BP and factor I but also newly discovered regulators such as SUSD4, CSMD1 and COMP. Recently we expanded our research into intracellular functions of complement proteins in particular in pancreatic beta cells.