Towards commercial production of sponge medicines

Abstract

Sponges can provide potential drugs against many major world-wide occurring diseases. Despite the high potential of sponge derived drugs no sustainable production method has been developed. Thus far it is not fully understood why, when, where and how these metabolites are produced in sponges. For the near future sea-based sponge culture seems to be the best production method. However, for controlled production in a defined system it is better to develop in vitro production methods, like in vitro sponge culture or even better sponge cell culture, culture methods for symbionts or the transfer of production routes into another host. We still have insufficient information about the background of metabolite production in sponges. Before production methods are developed we should first focus on factors that can induce metabolite production. This could be done in the natural habitat by studying the relation between stress factors (such as predation) and the production of bioactive metabolites. The location of production within the sponge should be identified in order to choose between sponge cell culture and symbiont culture. Alternatively the biosynthetic pathways could be introduced into hosts that can be cultured. For this the biosynthetic pathway of metabolite production should be unraveled, as well as the genes involved. This review discusses the current state of sponge metabolite production and the steps that need to be taken to develop commercial production techniques. The different possible production techniques are also discussed.

Keywords: bioactive metabolite; biosynthetic pathway; cell culture; sponge culture; sponge medicine.

Figure 1.

Sponges competing: (A) Dysidea avara (right) competing for space with a soft leather coral, (B) Aplysina aerophoba fouled with hydrozoa, (C) Haliclona oculata predated by a nudibranch.

Figure 2.

Flow sorting using flow cytometry. Cells can be charged based on difference in fluorescence or size (http://missinglink.ucsf.edu/lm/molecularmethods/flow.htm).

Figure 3.

Different attachment forms for sea-based culture. Sponges on (A) threads, (B) in cages, (C) on tiles, attached using a plastic band, where sponges attach to the tile themselves within one month.

Figure 4.

Development of sponge cell-lines. (A) Dysidea avara (B) cells isolated from Dysidea avara (C) bioreactor to culture animal cells.