Use of iodinated hyaluronan derivatives to study hyaluronan binding, endocytosis, and metabolism by cultured cells

We have described several simple procedures to determine whether cells have specific receptors or binding proteins for HA. The advantage of using the uniquely modified ¹²⁵I-labeled HA as a probe is that low levels of binding can be detected. It has been straightforward and productive to use ¹²⁵I-labeled HA to quantitate cell surface and intracellular binding sites to determine affinity constants for HA binding and to determine whether the cell type being studied can efficiently endocytose and degrade the HA. The ¹²⁵I-labeled HA preparations and assays described here and in Chapter 26 provide a very useful array of methods for studying the biochemistry and cell biology of HA.