Associate Professor Suzan Rooijakkers

The goal of the research of Susan Rooijakkers is to unravel the molecular mechanisms underlying bacterial killing by the human immune system. In particular, she investigates the molecular functioning of the complement system, a large protein network in plasma that plays an essential role in the immune response against all invading bacteria. Complement rapidly labels bacteria for phagocytosis by immune cells and directly kills Gram-negative bacteria via pore formation (Membrane Attack Complex (MAC)). Although the MAC is an evolutionary conserved mechanism to kill bacterial cells, we currently do not understand how complement activation results in bacterial killing. In 2015, she obtained the prestigious ERC Starting grant that is aimed at providing insight into these bacterial killing mechanisms. She has recently established novel methods to study complement activation in highly purified model systems allowing us to provide insight into MAC-dependent killing of bacteria.

Other projects in the lab involve unravelling processes underlying complement-mediated phagocytosis. Complement is essential in immune eradication of Gram-positive bacteria. She aims to elucidate the molecular details of complement opsonin-receptor interactions . The work will pave the way for several therapeutic applications, including targeted complement-dependent cytotoxicity (CDC) and antibody therapy of clinically important Gram-positive bacteria. Furthermore, her studies will create new avenues for blocking the undesired complement activation during systemic bacterial infections and sepsis.