Effect of calcium alginate concentration on viability and proliferation of encapsulated fibroblasts

Alginate hydrogels have been used widely in tissue engineering for cell encapsulation for several reasons: low toxicity, the ability to gel under gentle condition and compatibility with cells. In this study, we determined the effect of different concentrations of alginate on encapsulation of 3T3 fibroblast cells at two different cell seeding densities. Live/dead staining and MTT assay were performed at regular intervals up to 4 weeks. A Hoechst 33258 assay was done to validate the MTT results. There were more dead cells on day 1 for the higher concentrations of alginate while at, the lower concentration of alginate, cell proliferation and spheroid formation occurred more quickly. Furthermore, at low cell seeding density, cell proliferation was prolonged compared to the intermediate seeding density. In conclusion, by altering both alginate concentration and cell seeding density, proliferation and spheroid formation can be controlled.