Assessment of Growth Plate Chondrocytes Proliferative Activity in Embryonic Endochondral Ossification via Ki-67 Immunofluorescence.

Cell proliferation is one of the key events that regulates organism development. In the limb, chondrocytes differentiate into a multi-layered cellular template called the growth plate. Chondrocyte proliferation is essential to provide the necessary cells that allow growth of a bone. Deregulated cell proliferation will lead to truncated bone elements. Immunofluorescence is a biological technique that uses specific antibodies to detect the subcellular localization of a proliferative marker within cellular or tissue context. In this chapter, we illustrate how to perform immunofluorescence to detect the localization of Ki-67 (a marker of actively growing/proliferating chondrocytes) in order to assess the growth fraction of the columnar chondrocytes in the growth plate in paraffin-embedded mouse tissue limb.