To investigate the dynamic of macrophage polarization during Salmonella infection in vivo, we used the double transgenic line Tg(mfap4:mCherry-F/tnfa:GFP-F) in which all macrophages express a farnesylated mCherry and cells producing Tnfa, express GFP-F (Nguyen-Chi et al., 2015). The gene discussed is TNF; the disease is Salmonella Infections.