ROle of Apoptosis in Lymphocyte Depression (ROALD) - 01.09.14
Science Objectives for Everyone ROle of Apoptosis in Lymphocyte Depression (ROALD) will determine the role of programmed apoptosis (cell death) in loss of T-lymphocyte (white blood cells originating in the thymus) activity in microgravity.
Science Results for Everyone Information Pending
Sponsoring Space Agency
European Space Agency (ESA)
ISS Expedition Duration
October 2008 - April 2009
Previous ISS Missions
- ROle of Apoptosis in Lymphocyte Depression (ROALD) will to determine the role of programmed cell death (apoptosis) in loss of T-lymphocyte activity in microgravity.
- Various aspects of the apoptotic process will be assessed, using human T-lymphocytes, by analyzing gene expressions of metabolites of reactive oxygen species and membrane properties.
Experiments performed during spaceflight clearly show that several cellular processes, such as oxidative metabolism, growth rate, signal transduction and gene expression, are modified under conditions of weightlessness. For example, these alterations are associated with atrophy in heart, muscle and bone. In particular, dramatic effects of conditions similar to those that occur during exposure of cells to microgravity have been shown on the activation of human lymphocytes in vitro, and have been associated with:
- altered distribution and downregulation of protein kinase C,
- reduced expression of interleukin-2 and its receptor,
- microtubule anomalies and growth retardation, and
- altered cytoskeletal gene expression.
The experiment will further our understanding of the mechanisms by which microgravity and spaceflight factors influence immune cell function. In particular the effect on activation of apoptosis has not been explored. Although preparatory experiments can be performed with ground based techniques, such as the Random Positioning Machine (RPM) the effect of microgravity and cosmic radiation for the duration required for this experiment can only be explored using an orbiting space vehicle.
The experiment will be uploaded on Space Shuttle in passive thermal control unit to maintain the temperature above +25 degrees C to ensure good viability of the samples. Upon arrival to ISS, the ECs are installed in the Kubik incubator, pre-warmed to +37 degrees C. Experiment operations are performed automatically, once installed in Kubik following a short pre-incubation period the experiment is started by adding activator. A first set of samples is transferred to frozen stowage (-20 degrees C or colder) for 3-hours after activation, while the remaining samples are fixed with RNAlaterTM at 24-hours and 48-hours after activation, then transferred to frozen stowage. Samples must be maintained frozen following completion of the experiment, including during download.
Battista N, Meloni MA, Bari M, Mastrangelo N, Galleri G, Rapino C, Dainese E, Finazzi-Agro A, Pippia P, Maccarrone M. 5-Lipoxygenase-dependent apoptosis of human lyphocytes in the International Space Station: data from the ROALD experiment. Federation of American Societies for Experimental Biology Journal. 2012; 26(5): 1791-1798.
Ground Based Results Publications
Maccarrone M, Battista N, Meloni MA, Bari M, Galleri G, Pippia P, Cogoli A, Cogoli A, Finazzi-Agrņ A. Creating conditions similar to those that occur during exposure of cells to microgravity induces apoptosis in human lymphocytes by 5-lipoxygenase-mediated mitochondrial uncoupling and cytochrome c release. Journal of Leukocyte Biology. 2003; 73: 472-481.
Model of microgravity-induced apoptosis in human lymphocytes. Image courtesy of ESA.
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