Recommended procedure
Reconstitute the bone slices with media before initiating the pit assay. Mature or premature osteoclast
either generated from peripheral blood monocytes (PBMC) or co-cultures can be plated on the bone slices.
Dependent on the maturation state of the osteoclasts and the factors present, resorption pits will appear
after 3-14 days. The number of osteoclasts present can be visualized by its TRAcP activity, while the
formation of resorption pits and trenches can be visualized by toluidine blue staining (see Figure 2).
![Lab research](images/without-osteoclast.jpg)
Figure 1:
Bovine cortical bone slides without human osteoclast.
![Lab research](images/with-osteoclast.jpg)
Figure 2:
Bovine cortical bone slides with human osteoclast for 3 days.
Osteoclastic bone resorption result in the formation of resorption pits which can be used to monitor
the
resorption of the cultured osteoclasts.