Microglia purified from adult mice injected intracerebrally with OVA efficiently stimulated OVA-specific CD8+ T cells, suggesting that microglia can take up exogenous antigens and cross-present them on MHC-I molecules in vivo.94 In the VSV encephalitis model, microglia internalize antigens from infected neurons and cross-present them to antiviral CD8+ T cells, which allows the noncytolytic clearance of infection from neurons86 (Fig. 2). This evidence concerns the gene CD8A and viral encephalitis.