Fig. 2.

Induction of autophagy in vitro leads to decreased osteoclast formation in critically ill patient PBMCs. (a) The formation of mature, multi-nuclear (≥3 nuclei, tartrate-resistant acid phosphatase (TRAP) positive) osteoclasts was quantified visually using ImageJ software. (b) After 14 days in culture, osteoclast formation increased by 65 % in PBMC cultures from critically ill patients than those from healthy controls. The addition of rapamycin did not alter osteoclast formation in healthy control cultures, however, in patient cultures, osteoclast formation was reduced by 36 % (n = 6; *p < 0.05; ***p < 0.001)