Bioprinted Living Coral Microenvironments Mimicking Coral‐Algal Symbiosis

Abstract

The coral‐algal symbiosis is the biological engine that drives one of the most spectacular structures on Earth: the coral reef. Here, living coral microhabitats are engineered using 3D bioprinting, as biomimetic model system of the coral‐algal symbiosis. Various bioinks for the encapsulation of coral photosymbiotic microalgae (Breviolum psygmophilum) are developed and coral mass transfer phenomena are mimicked by 3D bioprinting coral tissue and skeleton microscale features. At the tissue–seawater interface, the biomimetic coral polyp and connective tissue structures successfully replicate the natural build‐up of the O2 diffusive boundary layer. Inside the bioprinted construct, coral‐like microscale gastric cavities are engineered using a multi‐material bioprinting process. Underneath the tissue, the constructs mimic the porous architecture of the coral aragonite skeleton at the micrometer scale, which can be manipulated to assess the effects of skeletal architecture on stress‐related hydrogen peroxide (H2O2) production. The bioprinted living coral microhabitats replicate the diffusion‐related phenomena that underlie the functioning and breakdown of the coral‐algal symbiosis and can be exploited for the additive manufacturing of synthetic designer corals.

Modeling the radiative, thermal and chemical microenvironment of 3D scanned corals

“…Finally, the presented 3D modelling approach can also be used to simulate different time-dependent environmental conditions (e.g., variable flow, day-night hypoxia, different solar irradiation regimes), which can help evaluating mechanisms driving coral stress responses as well as basic niche shaping factors for symbionts and microbiomes in the coral holobiont. The model could also be useful in more applied research such as in the ongoing attempts to create bionic corals (Wangpraseurt et al, 2022; Wangpraseurt et al, 2020) or for optimization of other 3D bioprinted constructs (Krujatz et al, 2022), where different designs can be evaluated and optimized. Our approach is also relevant for simulating structure-function relationships in other benthic systems such as photosynthetic biofilms and aquatic plant tissue, and can also be adapted to other sessile organisms such as symbiont-bearing giant clams, ascidians, jellyfish or foraminifera.…”

Phenotypically Complex Living Materials Containing Engineered Cyanobacteria

“…Clark-type O 2 microsensors (tip size 25–50 μm, Unisense, Aarhus, Denmark) were used to measure the O 2 microenvironment and O 2 turnover of the living hydrogels in light and in darkness. Microsensor measurements were performed as described previously 51,52 . O 2 sensors were mounted on a motorized micromanipulator (MU1, PyroScience GmbH, Germany) that was attached to an optical table.…”

“…Microsensor measurements were performed as described previously 51,52 . O2 sensors were mounted on a motorized micromanipulator (MU1, PyroScience GmbH, Germany) that was attached to an optical table.…”

Engineered photoresponsive biohybrids for tumor therapy

“…coral restoration). 167,168 Such hybrid living photosynthetic biomaterials could find wide applications in biomedical engineering and environmental applications.…”

“…Additionally, hybrid photosynthetic biomaterials have been fabricated via 3D bioprinting for efficient algal cultivation in algal biotechnology and for environmental applications (e.g. coral restoration) 167,168 . Such hybrid living photosynthetic biomaterials could find wide applications in biomedical engineering and environmental applications.…”