IL-18BP^−/−mice display normal growth and no spontaneous proinflammatory phenotype. (Ai) Schematic representation of WT and knockout (−/−) mouse Il18bp alleles is shown. Coding exons appear as white boxes, and noncoding exons as black boxes. Targeting vector-derived sequences in the targeted allele are shown in gray, between brackets. Triangles represent LoxP sequences. Location of primers designed for genotyping (P1 and P2 for WT allele, P3 and P4 for −/− allele) is indicated. (Aii) PCR products for the WT and targeted allele in −/−, heterozygous (+/−) and WT mice (+/+) are shown. (B) The mean body weight (± SD) of 20 male and 16 female WT littermates (+/+) and 10 male and 9 female IL-18BP^−/− (−/−) mice between 3 and 12 weeks of age is reported. (Ci) White and (Cii) red blood cell counts as well as (Ciii) platelet counts are shown for naive WT littermate and IL-18BP^−/− mice (n = 11). Data were pooled from 2 independent experiments. The number of (Di) total and CD45⁺ cells, (Dii) total T cells, CD4⁺ T cells, CD8⁺ T cells and B cells, and (Diii) conventional DCs (cDCs), plasmacytoid DCs (pDCs), monocytes/macrophages (mono/macro), and neutrophils (neutro) in the spleen are shown for naive WT littermates and IL-18BP^−/− female mice (n = 5, data are from 1 experiment representative of 2). The Mann-Whitney U test was used to compare WT and IL-18BP^−/− mice. ns, nonsignificant.