Synthesis and composition of glycosaminoglycans by explant cultures of human ciliary body and ciliary processes in serum-containing and serum-free defined media.

Freshly isolated ciliary body explants and tips of ciliary processes derived from human eyes were cultured in serum-containing or serum-free defined medium. These cultures synthesized tissue-bound and medium-released ("excreted") glycosaminoglycans (GAGs), as evidenced by the incorporation of 14C-glucosamine and enzymatic characterization of these labelled GAGs (hyaluronic acid, heparan sulphate, chondroitin sulphate, dermatan sulphate). The GAG synthesis and excretion rate was enhanced by serum. It is suggested that ciliary epithelium performs this function of GAG synthesis also under in vivo conditions.