Conservation and divergence of vulnerability and responses to stressors between human and mouse astrocytes

Human-mouse differences are a major barrier in translational research. Astrocytes play important roles in neurological disorders such as stroke, injury, and neurodegeneration. However, the similarities and differences between human and mouse astrocytes are largely unknown. Combining analyses of acutely purified astrocytes, experiments using serum-free cultures of primary astrocytes, and xenografted chimeric mice, we found extensive conservation in astrocytic gene expression between human and mouse. However, genes involved in defense response and metabolism showed species differences. Human astrocytes exhibited greater susceptibility to oxidative stress than mouse astrocytes, due to differences in mitochondria physiology and detoxification pathways. Mouse astrocytes, but not human astrocytes, activate a molecular program for neural repair under hypoxia. Human astrocytes, but not mouse astrocytes, activate the antigen presentation pathway under inflammatory conditions. These species-dependent properties of astrocytes may contribute to differences between mouse models and human neurological and psychiatric disorders.