In vitro, VVL-21-infected DT6606 cells were able to increase expression of the M1 marker major histocompatibility complex (MHC)II and decrease expression of the M2 marker CD206 in co-cultured macrophages (figure 4B, C) and both M1-polarized (figure 4D) and M2-polarized (figure 4E) macrophages showed an increase in MHCII after infection with VVL-21 compared with VV CTRL. Here, MRC1 is linked to infection.