a, Serum derived from the blood of naïve or Y. pestis infected non-human primates (NHP, Cynomolgous macaque) or human blood donors described in Fig. 5a (donors 1–5) was analyzed for IgG specific for F1 antigen (αF1) via ELISA. b, List of amino acids changes deduced following cloning and sequencing of FPR1 and CCR5 alleles from human blood neutrophils (donors 1–5). c, Quantification of Y. pestis KIM D27 (pMM83) translocation of YopM-Bla into U937 or FPR1−/− macrophages transfected with plasmids pFPR1 and pFPR1 R190W. d, Immunoblot analysis for the production of FPR1, FPR2, FPR3 and actin in U937 macrophages, and derived FPR1−/− cells un-transfected or transfected with pFPR1 and pFPR1 R190W, respectively. One of three repeats is shown (a, c). Error bars represent the s.e.m. (n = 3 biological replicates) (a, c). One-way ANOVA and Bonferroni’s post-hoc analyses (c) was used to identify significant differences: ***, P<0.001.