A novel cryoprotectant for marine sponges and beyond

A cryobank of more than 125 species of marine sponges has been created to further research to develop cell lines[1] for sustainable production of marine-derived chemicals with human health applications[2], creating models to test impacts of environmental deterioration[3], sponge habitat restoration, and biodiversity preservation. Our standard cryoprotectant is composed of 10% DMSO and 10% fetal bovine serum (FBS) in artificial seawater (ASW) where cells are stored at – 80°C[4]. Since a –80°C freezer is not always available for field based cryopreservation of sponge cells and the use of DMSO and FBS results in multiple technical and practical issues, we initiated the evaluation of a novel polymer-based medium product without any cell permeating or serum components, in which cells can also be stored at –20°C: DoriSol® (CryoCrate, USA)[5,6].

Our aims were to: (1) determine the necessity of DMSO cryoprotectant, (2) measure the effects of storage duration on viability; and (3) evaluate post-thaw differentiation and proliferation. We concluded that DoriSol® yielded sponge cells with high viability regardless of storage duration. Cells cryopreserved in DoriSol® were also more uniform morphologically than those cryopreserved using DMSO and FBS. All cryopreserved cells differentiated less than freshly dissociated sponge cells, but DoriSol® promptly improved post-thaw cell colony formation. Favorable results of cryopreserving sponge cells in DoriSol® have important implications for cryopreservation and storage of marine sponge cells—and cells of other marine invertebrates—in the field.