FIG 4.

YopJ suppresses immune cell recruitment to foci of bacterial growth in liver tissue. (A) Representative liver sections stained with hematoxylin and eosin from mice 48 h after intravenous infection with 10³ CFU KIM1001 (wild type [w.t.]), KIM1001ΔT3SE::+yopHEKMAJT (complemented), KIM1001ΔT3SE::+yopHEKMJ (+yopHEKMJ), KIM1001ΔT3SE::+yopHEKM (+yopHEKM), KIM1001ΔT3SE::+yopHEKMA (+yopHEKMA), or KIM1001ΔT3SE::+yopHEKMT (+yopHEKMT). Strains with a functional yopJ allele grow freely in liver tissue without attracting inflammatory cells (top row), in contrast to strains deficient in yopJ (bottom row). (B) Severity of inflammation was scored on an arbitrary scale (1, free bacteria with few or no inflammatory cells; 5, abundant inflammatory cells with few or no visible free bacteria). Each data point represents the average score for 10 lesions from a single mouse. Data are representative of two independent blind scorings. *** denotes a P value of <0.001 (two-tailed unpaired t test).