A critical role for MSR1 in vesicular stomatitis virus infection of the central nervous system

Summary Macrophage scavenger receptor 1 (MSR1) plays an important role in host defense to bacterial infections, M2 macrophage polarization, and lipid homeostasis. However, its physiological function in viral pathogenesis remains poorly defined. Herein, we report that MSR1 facilitates vesicular stomatitis virus (VSV) infection in the central nervous system. Msr1-deficient (Msr1−/−) mice presented reduced morbidity, mortality, and viral loads in the spinal cord following lethal VSV infection, along with normal viremia and innate immune responses, compared to Msr1+/− littermates and wild-type mice. Msr1 expression was most significantly upregulated in the spinal cord, the predominant target of VSV. Mechanistically, through its extracellular domains, MSR1 interacted with VSV surface glycoprotein and facilitated its cellular entry in a low-density lipoprotein receptor-dependent manner. In conclusion, our results demonstrate that MSR1 serves as a cofactor for VSV cellular entry and facilitates its infection preferentially in the spinal cord.
Graphical abstract
Highlights • MSR1 contributes to VSV pathogenesis in mice • MSR1 is highly upregulated and facilitates VSV infection in the central nervous system • MSR1 facilitates cellular entry of VSV in an LDLR family-dependent manner • MSR1 interacts with VSV glycoprotein G via its extracellular domains
Molecular physiology; Neuroscience; Virology; Cell biology