Matrix remodeling during intervertebral disc growth and degeneration implicated by FAST staining

Various imaging techniques have been widely used to study intervertebral disc (IVD) biology, among which histological methods are most common as they are indispensable tools to retrieve structural information. Stainings using Alcian blue-fast red and safranin-O-fast green are popular but they have limitations in delineating the complex structures of the IVD comparing to their use for articular cartilage. Triple dye methods, including picrosirius red-alcian blue-hematoxylin and Masson’s trichrome have been recently used with some success. As proteoglycan is a major component of the IVD, we hypothesize that a synergistic staining with dyes suggestive of glycoprotein interaction may generate a structural image of IVD with enhanced resolution. We have established a novel multi-chromatic staining protocol for assessment of the IVD using a combination of Fast green, Alcian blue, Safranin-O, and Tartrazine stains (FAST staining). The aim of this study is to test if the FAST staining protocol can reveal fine structure of the IVD as well as provide insight about changes of extracellular matrix (ECM) during disc growth and degeneration using animal models.