Immunolocalization of hyaluronic acid and inter-alpha-trypsin inhibitor in mice

Abstract

 The direct interaction of hyaluronic acid (HA) and heavy chain (HC) of the inter-alpha-trypsin inhibitor (IαI) family plays a critical role in the organization and stabilization of the extracellular matrix. The aim of the present investigation was to elucidate the distribution of the IαI HC and HA in adult mouse tissues. An immunohistochemical method using a rabbit polyclonal antibody raised against mouse IαI heavy-chain peptide and a specific probe for HA (biotinylated HA-binding protein) was used to demonstrate an immunolocalization of IαI HC and HA. Distribution and localization of HA was of three types, namely, colocalization with IαI HC itself (cartilaginous tissue and ovary), localization around IαI HC immunostaining (lung, intestine and skeletal muscle), and localization at a small distance from IαI HC or a different distribution pattern (brain, liver, skin and kidney). These results indicate that IαI HC could function as an HA-rich matrix stabilizer on the cells of cartilage and maturing ovary, in which IαI HC shows colocalization with its predominant ligand, HA.