TGFB1 and infection: Throughout all stages of infection in the susceptible C57BL/6 strain, the increase in the myelination pathway is driven by the genes Hexb, Tgfb1, and Cxcr4. Hexb encodes enzymes in lysosomes that break down toxic substances and act as recycling centers (Mahuran, 1999; Ogawa et al., 2018).