Preliminary results on cosmic radiation effects in T lymphocytes

Experiments carried out In space and In clinostate demonstrated the influence of microgravity on mitogenic activation of human T lymphocytes at molecular level. To discriminate between effects of microgravity and cosmic radiations. in this work we studied the effects of cosmic radiations on the genetic expression in human T cells boarded In a stratospheric balloon (BIRBA-1 mission. 22 hours of flight). The genetic expression was analyzed by the eDNA microarray. which allows the comparutive and simultaneous estimate of hundreds of mRNAs.Actlvated cells react to the ionizing stress by activating genes involved in cell cycle check-point. oxidative stress response. heat shock proteins production or by repressing genes involved in antigen recognition.