a, Gating strategy for total lung myeloid populations. b, Frequency of tumour-ingesting myeloid cells in the lung over 24 h following i.v. injection with B16ZsGreen (n = 6, error bars are standard deviation). c, Frequency of myeloid cells in total lung cells over 24 h following i.v. injection with B16ZsGreen (n = 6). d, Frequency of intravascular versus extravascular myeloid populations at 4 or 24 h following i.v. injection of B16ZsGreen cells (n = 6 per group; *P < 0.05, two-way ANOVA with multiple comparison between row and column means, error bars are standard deviation).