"3D microenvironment maintains the transcriptome profile of T cells but not B cells in simulated microgravity
The adverse effects of space travel on the human body are abundant and with the rise in interest in manned spaceflight over recent years, there is an increased need for more research into these effects. In the absence of gravitational forces, one of the primary systems to be negatively affected is the immune system and its dysregulation leads to increased susceptibility of astronauts to infections. Lymphocytes (T and B cells), the key players of the adaptive immune system, are involved in fighting infections and producing antibodies. Currently, less is known to which extent microgravity affects lymphocyte functions. To address the above mentioned question, we utilized 2D tissue culture plastic and 3D collagen matrices, the latter better mimics the in vivo cellular microenvironment, as cell culture models. T and B cells were cultured on ground and under simulated microgravity conditions. Both cell types were also analyzed under resting and activated states using RNA-Sequencing. Our data indicates that the 3D culture microenvironment appears to maintain the transcriptome profile of T cells but not B cells during early activation under simulated microgravity conditions when compared to ground controls. In T cells, DNA damage and protein degradation were upregulated in 2D cell culture under simulated microgravity conditions whereas the 3D microenvironment prevents these adverse effects. Interestingly, B cells showed a higher number of differentially expressed genes when activated in 3D collagen matrices compared to 2D cell culture. However, simulated microgravity conditions attenuates these effects. Overall, our results suggest that the cellular microenvironment plays a role on lymphocyte behavior on Earth and in simulated microgravity."