SCD – Stem Cell Differentiation on board the International Space Station [microarray on total RNA]

The bone loss observed in astronauts and animal models after spaceflight is attributable to alterations in the bone tissue formation that depends from the continuous remodeling through the activities of bone-resorbing osteoclasts of hematopoietic lineage and bone-forming osteoblasts of mesenchymal origin. This disease is frequent in aged people, but develops much more rapidly in space. Our experiment, selected by ESA (European Space Agency), aimed to determine how human bone marrow mesenchymal stem cells (hBMSCs) react and differentiate in real microgravity, on board the International Space Station, in approx. 2 weeks time. The SCD experiment consisted of 24 experimental hardware modules (EH) (12 flight modules and 12 ground modules), each of which had one experiment unit (EU) integrated into the KUBIC interface container single level (KIC-SL). Each EU consisting of a brick containing 5 cylinders (for the medium and chemicals), a cell culture chamber (CC), and connecting channels. Five small valves were placed to separate the different fluids and the CC. Each cylinder had a piston to inject a new fluid into the CC; the waste medium was collected in the previously emptied cylinder and suitably preserved. EH were trasferred on board the ISS by the Soyuz-TMA-16M (ISS 42S, launched on March 27, 2015); 27°C was the temperature recorded for the samples in the Soyouz vehicle before docking and installation in the KUBIK incubator on board the ISS The experimental proifile consisted of: 1) installation in KUBIK (T0); 2) Start with the first medium exchange (T0+7h); 3) Second medium exchange (T0+7d); 4)Third medium exchange with PBS (T0+14d); 5) Stop by means of two subsequent exchanges with RNAlater Here, the effect of microgravity on hBMSCs were investigated by means of microarray analysis of total RNA.