Project B2 will continue to assess the role of C5a-mediated crosstalk between DCs and NK cells to control T. gondii infection. A particular focus will be on the NK/DC synapse. Projects B3, B4 and B7 center around the diverse roles of neutrophils in infection. The exciting results on the immunoregulatory roles of PNACs in L. major infection and sepsis will be further assessed in project B3. Project B4 focuses on the regulation of anti-microbial neutrophil functions by small GTPases. Building on its findings from the 1st funding cycle, project B6 will determine the impact of Tr1 cells on the susceptibility and vaccination efficacy in Mtb infection. Project B7 investigates the interaction of neutrophils with macrophages and its impact on innate and adaptive immune responses in Mtb infection. Project B8 will continue to investigate the role of HIF-1a in H. capsulatum (Hc) infection with a particular emphasis on HIF-1a as master regulator between metabolic and inflammatory control of Hc-infected macrophages. Project B9 will assess, how L. monocytogenes is targeted from the circulation to CD8+ DCs in the spleen to mount appropriate pathogen-specific adaptive immune responses. The MD/PhD project focuses on the cross-talk between complement, myeloid and lymphoid regulatory cell and its impact on sepsis development in preterm infants.