History of Research on Cell Biology in Space

The purpose of this chapter is to present the results obtained in nearly thirty years of research with single cells in space laboratories and platforms. I have tried to select and report only those findings sustained by solid facts, based on proper controls and experimental conditions, and published in international peer-reviewed journals. In fact, still nowadays, a great many of biological experiments that are conducted in space lack of inflight 1-g controls, or of sufficient number of samples to provide statistical significance, or of reliable environmental control. Most of such investigations are reported

Figure 4-02. Within the Biolab facility, experiments on board the International Space Station can be incubated, stored at cool or cold temperatures, microscopically or photometrically analysed and freshly prepared, if required, allo-wing most of these features without crew interaction, but with telescience capability. Source ESA.

Figure 4-02. Within the Biolab facility, experiments on board the International Space Station can be incubated, stored at cool or cold temperatures, microscopically or photometrically analysed and freshly prepared, if required, allo-wing most of these features without crew interaction, but with telescience capability. Source ESA.

in agency brochures or presented at meetings as short abstracts. I firmly believe that it is deleterious to science to conduct such crippled investigations: the data are not reliable and support the skepticism and the hostility of part of the scientific community towards space biology.

The focus of this chapter is on gravitational effects, including those observed with Earth-bound devices providing vectorless gravity conditions, like clinostats and rotating wall vessels. The effect of cosmic radiation on living systems is discussed in another chapter of this book.

The development of space biology can be subdivided in four phases. In the first phase, from the early seventies to the mid-eighties, living systems were studied at random to look for detectable effects of the space environment. During the second phase, which lasted until the mid-nineties, several important effects on cellular mechanisms were discovered and characterized. We are presently in the third phase, which consists of the use of microgravity as a tool for basic research and medical diagnosis. Major topics addressed are genetic expression, cell-cell interactions, membrane properties (lipid rafts in particular), cytoslceleton changes and signal transduction. The fourth phase is at its beginning and is characterized by attempts to develop processes of biotechnological and medical importance. Space cell biology obviously develops in parallel with the progress of scientific achievements and of analytical techniques like the microarray, cyto-fluorimetic and specific markers technologies.

By now, about three hundred experiments in space have shown that single cells from all steps of the evolutionary ladder can live and proliferate in space, but that at the same time dramatic changes can occur. Unfortunately the catastrophe of Columbia's flight STS-107 has put on hold dozens of investigations that were selected for flights from 2003 onwards. Moreover, due to the hold of the Space Shuttle program, the beginning of the operations of the major biological facilities on the International Space Station (ISS) like Biolab (Figure 4-02) and the European Modular Cultivation System have been delayed by at least two to three years. Therefore, the use of ground-based facilities, like the fast rotating clinostat, the random positioning machine and the rotating wall vessel, which provide conditions simulating microgravity (see Chapter 3, Section 1.2), has gained great importance. As a consequence, many interesting data in gravitational cell biology of the last three years have been obtained on the ground.

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