Fig. 2

Representative immunohistological stainings of immune cells from the healthy control group 1, the osteochondral pathology group 2, the partial tear group 3 and the full-thickness tear group 4. The upper row shows CD45+ leukocytes, which are found mostly perivascular (v) in the 3 pathology groups and to a lesser extent in the healthy control group 1 (arrows). The lower row depicts CD68+ monocytes/macrophages, which are also more pronounced in pathological bursae (group 2–4) close to vessels (v) and sporadically detected in healthy bursae of group 1 (arrows). The scale bar represents 50 μm at 400x magnification