Miniaturized Platform for Individual Coral Polyps Culture and Monitoring

Abstract

Methodologies for coral polyps culture and real-time monitoring are important in investigating the effects of the global environmental changes on coral reefs and marine biology. However, the traditional cultivation method is limited in its ability to provide a rapid and dynamic microenvironment to effectively exchange the chemical substances and simulate the natural environment change. Here, an integrated microdevice with continuous perfusion and temperature-control in the microenvironment was fabricated for dynamic individual coral polyps culture. For a realistic mimicry of the marine ecological environment, we constructed the micro-well based microfluidics platform that created a fluid flow environment with a low shear rate and high substance transfer, and developed a sensitive temperature control system for the long-term culture of individual coral polyps. This miniaturized platform was applied to study the individual coral polyps in response to the temperature change for evaluating the coral death caused by El Nino. The experimental results demonstrated that the microfluidics platform could provide the necessary growth environment for coral polyps as expected so that in turn the biological activity of individual coral polyps can quickly be recovered. The separation between the algae and host polyp cells were observed in the high culture temperature range and the coral polyp metabolism was negatively affected. We believe that our culture platform for individual coral polyps can provide a reliable analytical approach for model and mechanism investigations of coral bleaching and reef conservation.

Morphological and Genetic Recovery of Coral Polyps After Bail-Out

“…Although in the present study, experiments were conducted only until 5 days postbail-out, recovered polyps survived for over 2 weeks in our preliminary experiments, without strict monitoring of recovery conditions (data not shown). This lifespan is comparable to those reported in previous studies applying microfluidic techniques for post-bail-out polyp cultivation, in which recommencement of skeletogenesis was even observed (Shapiro et al, 2016;Luo et al, 2020;Pang et al, 2020). Based on morphological observations and computational modeling, Pang et al (2020) suggested that continuous supply of DO (dissolved oxygen) and DIC (dissolved inorganic carbon) is essential for long-term cultivation of isolated polyps.…”

“…In recent decades, advances in microfluidic and molecular techniques have made it possible for coral research at polyp scale, the basic building blocks of coral colonies (Bromage et al, 2009;Shapiro et al, 2016;Luo et al, 2020;Pang et al, 2020). Individual polyps enable detailed visualization of cellular and molecular responses in corals, which is typically constrained at colony scale by the calcareous skeletons.…”

The history, biological relevance, and potential applications for polyp bailout in corals

“…Osmoregulatory stress (increase in salinity of >15‰) has been shown to induce polyp bailout in three different pocilloporid coral genera (Chuang et al, 2021;Chuang & Mitarai, 2020;Liu et al, 2020;Shapiro et al, 2016). Two other recent studies used calcium-free seawater as an artificial stressor to induce bailout in pocilloporid corals (Luo et al, 2020;Pang et al, 2020).…”

Microfluidic Technology and Biomedical Field

“…Luo et al studied the numerical simulation of oxygen and glucose transport to improve the functionality of biomedical microfluidic devices. They designed an integrated microfluidic device for the culture of individual coral polyps, including a uniform flow medium, rapid mass transfer, and precise temperature control [9]. The microfluidic device provided a reliable analytical approach for model and mechanism studies of coral bleaching and reef conservation.…”