Neutrophils and macrophages were FACS-sorted from mpx:eGFP (ref. 17) and mpeg1:eGFP (ref. 18) transgenic lines on infection with ST, respectively, and it was found that Gbp4 transcripts were highly enriched in neutrophils, while they were hardly detected in macrophages (Fig. 1b,c). The gene discussed is GBP4; the disease is infection.