Interleukin-12 signaling drives Alzheimer’s disease pathology through disrupting neuronal and oligodendrocyte homeostasis
Shirin Schneeberger, Seung Joon Kim, Maria Geesdorf, Ekaterina Friebel, Pascale Eede, Marina Jendrach, Anastasiya Boltengagen, Caroline Braeuning, Torben Ruhwedel, Andreas J. Hülsmeier, Niclas Gimber, Marlene Foerster, Juliane Obst, Myrto Andreadou, Sarah Mundt, Jan Schmoranzer, Stefan Prokop, Wiebke Kessler, Tanja Kuhlmann, Wiebke Möbius, Klaus‐Armin Nave, Thorsten Hornemann, Burkhard Becher, Julia M. Edgar, Nikos Karaiskos, Christine Kocks, Nikolaus Rajewsky, Frank L. Heppner
Abstract
Neuroinflammation including interleukin (IL)-12/IL-23-signaling is central to Alzheimer's disease (AD) pathology. Inhibition of p40, a subunit of IL-12/IL-23, attenuates pathology in AD-like mice; however, its signaling mechanism and expression pattern remained elusive. Here we show that IL-12 receptors are predominantly expressed in neurons and oligodendrocytes in AD-like APPPS1 mice and in patients with AD, whereas IL-23 receptor transcripts are barely detectable. Consistently, deletion of the IL-12 receptor in neuroectodermal cells ameliorated AD pathology in APPPS1 mice, whereas removal of IL-23 receptors had no effect. Genetic ablation of IL-12 signaling alone reverted the loss of mature oligodendrocytes, restored myelin homeostasis, rescued the amyloid-β-dependent reduction of parvalbumin-positive interneurons and restored phagocytosis-related changes in microglia of APPPS1 mice. Furthermore, IL-12 protein expression was increased in human AD brains compared to healthy age-matched controls, and human oligodendrocyte-like cells responded profoundly to IL-12 stimulation. We conclude that oligodendroglial and neuronal IL-12 signaling, but not IL-23 signaling, are key in orchestrating AD-related neuroimmune crosstalk and that IL-12 represents an attractive therapeutic target in AD.