TWIN project A 25 analyzes the interaction between the immune system and CNS with a focus on neurotrophins. In the 2nd funding period, A 25 studied neuroinflammation and early processes of neurodegeneration in the context of neurotrophin signaling via the p75NTR. In the 3rd funding period, A 25 will investigate immune cell function and neuronal architecture in mice lacking the neurotrophin BDNF specifically in neurons or in microglia/monocytes and in Bassoon-/- mice, which show increased BDNF secretion. Furthermore, A 25 will analyze how signaling of the neurotrophin receptor Nogo-A via NgR1/p75NTR controls microglia/monocyte behavior and affects neuronal architecture and function.