ACP5 and infection: B. pseudomallei-infected RAW264.7 murine macrophages are induced to form MNGCs during infection with increased expression of calcitonin receptor (CTR), cathespin K (CTSK), and tartrate-resistant acid phosphatase (TRAP), markers which are hallmarks of functional osteoclasts, natural MNGCs formed from the fusion of mononuclear cells [177,178], although further work showed that B. pseudomallei-induced MNGCs are only osteoclast-like [177].