Microgravity effect on the differentiation of FLG 29.1 cells, an osteoclastic precursor model

Experiments on single cell in microgravity represent a chance to increase the knowledge on molecular organization, genetics, growth, proliferation, differentiation and activation, morphological characteristics. In this paper, a study is presented on the behaviour of FLG 29.1 cells, an osteoclastic precursor model, in simulated microgravity conditions. Changes of strains on cell surface can modify the cytoskeleton structure and, consequently, cell functions. The effect of weightless in terms of cell differentiation induction has been analysed by application of advanced optical techniques, i.e. auto fluorescence spectroscopy and multispectral imaging autofluorescence microscopy (MIAM). Under microgravity conditions, the interaction between cells and substances inducing differentiation (phorbol esters) or substances inducing cell adhesion was also investigated. Together with the characterization of morphologic and metabolic aspects, a measure of bone resorption activity was performed by the application of an original method based on profile measurements. The aim of the work was that to study microgravity effects on bone metabolism, as well as to approach the more general problem of strain application on cell surface.