Figure 3.

Msr1 is critical for VSV infection in the central nervous system

(A–C) Quantitative RT-PCR analyses of VSV loads in (A) different tissues of Msr1^+/− and Msr1^−/− littermates on day 6 after infection (N = 3 mice/genotype), (B) the spinal cords, and (C) the brains of Msr1^+/− and Msr1^−/− littermates on day 6 after infection (N = 6 mice/genotype). The viral RNA load is expressed as fold changes over the limit of detection (LOD).

(D) The VSV titers in the spinal cord and brain of Msr1^+/− and Msr1^−/− littermates on day 6 after infection, assessed by a plaque-forming assay (N = 6 mice/genotype).

(E) Msr1 mRNA expression (expressed as a fold change over the mock spinal cord group) in different tissues of mock and VSV-infected Msr1^+/− mice on day 6 after infection, N = 3 mice/group.

(F–H) (F) Correlation between Msr1 expression and VSV load in various tissues after VSV infection, N = 3 mice/group. The mRNA expression of class A and B scavenger receptors in (G) the spinal cord and (H) the brain of mock and VSV-infected Msr1^+/− and Msr1^−/− littermates on day 6 after virus inoculation, assessed by quantitative RT-PCR and expressed as a fold change over the Msr1^+/--mock group, N = 3 mice/group.

(I) Ldlr mRNA expression in the brain and spinal cord of mock and VSV-infected Msr1^+/− and Msr1^−/− littermates, expressed as a fold change over the brain of Msr1^+/--mock group, N = 3 mice/group, ∗p < 0.05 vs brain, analyzed by non-parametric Mann-Whitney U test. Mock: no virus infection control.

(J) Colocalization of MSR1 with microglia, astrocytes, and neurons in the mouse spinal cord by dual immunofluorescence staining. IBA1: a marker of microglia; GFAP: a marker of astrocyte; MAP2: a marker of neuron; DAPI: nuclei. The yellow regions in the overlay indicate colocalizations. Scale bar represents 10 μm. All the data are presented as mean ± S.E.M., and statistical significances are analyzed by non-parametric Mann-Whitney U test, ∗p < 0.05, ∗∗p < 0.01.