Cd47 deficiency in mouse brain under excitotoxic stress
Mehrdad Kiamari, Amalia Perna, Matteo Santoro, Abdel El Ariss, Eloise Berson, Jing Zhao, Chandresh R. Gajera, Edward J. Fox, Kathleen S. Montine, Nima Aghaeepour, Thomas J. MontineCD47, a transmembrane protein with well-established immune and neurodevelopmental roles, was recently identified as an abundant presynaptic protein in humans, non-human primates, and mice. To investigate how Cd47 influences neuronal stress and injury, we performed single-nucleus RNA sequencing of hippocampi from wild-type (WT) and Cd47 knockout (KO) mice exposed to kainic acid (KA) at convulsive (KA25; 25 mg/kg) or subconvulsive (KA3; 3 mg/kg) doses. Integrating cell-type annotations with Weighted Gene Co-expression Network Analysis (WGCNA) revealed distinct neuronal and glial gene modules whose co-expression structure differed by genotype and by KA exposure. Notably, certain modules showed KA-associated changes in co-expression structure only in Cd47 -deficient cells. Enrichment analyses of these modules highlighted translational, bioenergetic, and synaptic gene sets. Comparing transcriptome-wide distributions using Wasserstein distance demonstrated that vehicle-treated KO cells most closely resembled WT cells exposed to KA3, of all fifteen pairwise comparisons. These findings suggest that Cd47 loss shifts the hippocampal transcriptome toward a state resembling mild excitotoxic stress, implicating Cd47 as a candidate regulator of neuronal stress adaptation and providing a hypothesis for testing that role.