Fig. 2. Coagulases generate protective shields around staphylococcal abscess communities.

Kidneys were frozen in cryomatrix, thin-sectioned, stained with hematoxylin–eosin and images were captured by light microscopy and visualized with ×2, ×20, ×40 oil, and ×100 oil objectives. Renal tissues of mice infected with LAC, LAC & Δcoa, or LAC & ΔcoaΔvwbp had visible abscess lesions (×2 obj., white arrows). The staphylococcal abscess communities (×40 and ×100 obj.) were enclosed by an amorphous eosinophilic pseudocapsule (×20 and ×40 obj., black arrows), surrounded by a zone of dead/necrotic leukocytes (×20 obj.). The renal sections of mice infected with only cheats, Δcoa or ΔcoaΔvwbp, were absent of any characteristic abscess lesions (×2 obj.), displaying healthy tissue (×2 and ×20 obj.) and healthy leukocytes (×40 obj., yellow arrows, and ×100).