Mitogenic Activity of Sulfated Chitosan and Cellulose Derivatives is Related to Protection of FGF-2 from Proteolytic Cleavage

Novel chitosan (CHS) and cellulose sulfates (CSs) are studied regarding their mitogenic activity and their protective effect against proteolytic digestion of FGF-2. An intermediate degree of sulfation (DSS) and lower concentration of CHS have superior effect on 3T3 cell growth while the mitogenic activity of CS increases with DSS and concentration. Experiments with trypsin as model proteinase show that protection of FGF-2 from proteolytic digestion depends on DSS and the concentration of derivatives in the same manner as cell growth. Studies on stability of FGF-2 added to cultures of 3T3 cells show that the FGF-2 concentration remains higher in the presence of derivatives. Results indicate that the mitogenic activity of CHS and CS is due to protection of FGF-2 from proteolytic cleavage.