Fig. 2

Immunohistochemical staining for receptor activator of nuclear factor kappa B (RANK)/RANK ligand (RANKL)/osteoprotegerin (OPG) in cultured rat anulus fibrosus (AF), nucleus pulposus (NP) and cartilaginous endplate (CEP) cells. All the cells were cultured in monolayer for 3 days: a-d AF; e-h NP; i-l CEP. d, h, l Isotype controls. Samples were imaged using confocal microscopy. Immunoreactivity (green) is clearly seen in the AF, NP and CEP cells. Nuclei are stained with propidium iodide (red). Scale bar 10 μm