MMP7 and bacterial urinary tract infection: However, in embryos infected early in development with E. coli (UTI, Fig. 3h–l), absence of brain led to a significant increase in the number of mmp7+ cells in ventral areas respect to Ctrl animals (one-way ANOVA P < 0.05; Bonferroni’s posttest P = 0.0464 for BR– vs. Ctrl at ventral area; Fig. 3k), represented by the accumulation of this population along the ventral hematopoietic niche (Fig. 3m, n).