Applying model approaches in non-model systems: A review and case study on coral cell culture

Abstract

Model systems approaches search for commonality in patterns underlying biological diversity and complexity led by common evolutionary paths. The success of the approach does not rest on the species chosen but on the scalability of the model and methods used to develop the model and engage research. Fine-tuning approaches to improve coral cell cultures will provide a robust platform for studying symbiosis breakdown, the calcification mechanism and its disruption, protein interactions, micronutrient transport/exchange, and the toxicity of nanoparticles, among other key biological aspects, with the added advantage of minimizing the ethical conundrum of repeated testing on ecologically threatened organisms. The work presented here aimed to lay the foundation towards development of effective methods to sort and culture reef-building coral cells with the ultimate goal of obtaining immortal cell lines for the study of bleaching, disease and toxicity at the cellular and polyp levels. To achieve this objective, the team conducted a thorough review and tested the available methods (i.e. cell dissociation, isolation, sorting, attachment and proliferation). The most effective and reproducible techniques were combined to consolidate culture methods and generate uncontaminated coral cell cultures for ~7 days (10 days maximum). The tests were conducted on scleractinian corals Pocillopora acuta of the same genotype to harmonize results and reduce variation linked to genetic diversity. The development of cell separation and identification methods in conjunction with further investigations into coral cell-type specific metabolic requirements will allow us to tailor growth media for optimized monocultures as a tool for studying essential reef-building coral traits such as symbiosis, wound healing and calcification at multiple scales.

Bioprinted Living Coral Microenvironments Mimicking Coral‐Algal Symbiosis

“…[ 67 ] For liquid cultures, trypan blue was diluted with culture media (50% v/v); which was passed through a 0.22 µm filter, and the resultant solution was added to liquid culture media in a 1:5 ratio. [ 67 ] Cell viability was immediately assessed via hemocytometer counting. For scaffolded cultures, the bathing media was drawn off scaffolds and then incubated with the trypan blue mixture (50% v/v) for 10 min.…”

“…Cell Viability: Cell viability in liquid cultures prior to 3D bioprinting and in hydrogels after printing was assessed via trypan (Sigma T8154) blue live/dead staining. [67] For liquid cultures, trypan blue was diluted with culture media (50% v/v); which was passed through a 0.22 µm filter, and the resultant solution was added to liquid culture media in a 1:5 ratio. [67] Cell viability was immediately assessed via hemocytometer counting.…”

Evaluation of fluorescence-based viability stains in cells dissociated from scleractinian coral Pocillopora damicornis

“…Tissue of scleractinian coral Pocillopora damicornis (green phenotype, Fig. 2 ) was dissociated from the skeleton using calcium and magnesium-free seawater incubation for 1 h as described in our earlier publication 4 . The mixture of cells was washed and resuspended in complete culture medium (CM, see “ Coral cell dissociation and culture ” section for details).…”

Oxybenzone contamination from sunscreen pollution and its ecological threat to Hanauma Bay, Oahu, Hawaii, U.S.A.

“…and European Union government regulatory agencies are advocating for the discontinuation of whole organism toxicity testing and shifting to New Approach Methods that utilize in vitro cell-toxicity testing for chemicals (Gwinn et al, 2020). Coral cells have been used to ascertain the toxicity of chemicals for over 10 years (Downs et al, 2010;Roger et al, 2021). Coral husbandry for ecotoxicological work is technically challenging and resource intensive.…”