Coral cell separation and isolation by fluorescence-activated cell sorting (FACS)

Abstract Background Generalized methods for understanding the cell biology of non-model species are quite rare, yet very much needed. In order to address this issue, we have modified a technique traditionally used in the biomedical field for ecological and evolutionary research. Fluorescent activated cell sorting (FACS) is often used for sorting and identifying cell populations. In this study, we developed a method to identify and isolate different cell populations in corals and other cnidarians. Methods Using fluorescence-activated cell sorting (FACS), coral cell suspension were sorted into different cellular populations using fluorescent cell markers that are non-species specific. Over 30 different cell markers were tested. Additionally, cell suspension from Aiptasia pallida was also tested, and a phagocytosis test was done as a downstream functional assay. Results We found that 24 of the screened markers positively labeled coral cells and 16 differentiated cell sub-populations. We identified 12 different cellular sub-populations using three markers, and found that each sub-population is primarily homogeneous. Lastly, we verified this technique in a sea anemone, Aiptasia pallida, and found that with minor modifications, a similar gating strategy can be successfully applied. Additionally, within A. pallida, we show elevated phagocytosis of sorted cells based on an immune associated marker. Conclusions In this study, we successfully adapted FACS for isolating coral cell populations and conclude that this technique is translatable for future use in other species. This technique has the potential to be used for different types of studies on the cellular stress response and other immunological studies

What Is Currently Known About the Effects of Climate Change on the Coral Immune Response

It is well documented that climate change has a negative effect on coral reefs worldwide. Recurrent warming events, ocean acidification, and nutrient pollution are some of the hallmarks of climate change; each affects the health of coral, and together, their effects are multiplied. It is hypothesized that a healthy coral will have a strong, highly active immune system when confronted with different stressors. However, there is very little that we understand about how the coral immune system reacts to different climate change stressors. In this review, we will examine what is known about the effects of heat stress, ocean acidification, and nutrient pollution on the coral immune system. We will identify gaps in our knowledge and briefly discuss a path forward to address these gaps