Isolation and primary culture of viable multicellular endothelial isolatesfrom hard corals

Conditions for the primary culture of branching scleractinian coral (Acropo ra micropthalma and Pocillopora damicornis) cells were established with a c alcium-free seawater cell dissociation method. Cells were isolated and cult ured in supplemented Dulbecco's modified Eagle media with heat-inactivated fetal bovine serum, antibiotics, and sterile seawater. Among the isolated c ell types, lar ge (60-100 mu m) multicellular endothelial isolates (MEIs) w ere seen in high numbers. These isolates were observed to continually spin for up to 300 h without media change. The following parameters were optimiz ed: media, serum, light, trace elements, and growth factor supplements. Rot ations per minute were calculated to determine MEI motility in relation to size. Finally, analyses of external and internal structures were conducted with scanning electron microscopy, transmission electron microscopy, and fl uorescence microscopy. Additional coral species, Montipora digitata, Stylop hora pistillata, Seriatopora hystrix and Porites sp. were also cultured to determine the applicability of isolation techniques. The relatively long su rvival time of MEIs in primary culture makes them ideal candidates for in v itro studies examining coral disease processes (e.g., mode of infection and intracellular effects of disease-causing agents) as well as aspects of gen eral coral growth and health (e.g., trace element requirements and transfer of products between host cell and zooxanthellae).