This week we want to show what we suspect to be mitochondria and what we could do to detect them with the 3D Cell Explorer.
In a recent publication, Haseda, Keisuke, et al. (2015) were able to determine the refractive index of an isolated mitochondria (~1.41) using retardation-modulated differential interference contrast microscopy with a precision of ± 0.01. The refractive index measurement of subcellular components gives information about the structures and the functions of cells.
This value could be useful for us to detect mitochondria in a complex cell structure.
Other publications have also determined the refractive index of different subcellular structures: the nucleus (~1.39) by R.Barer, S.Joseph (1954), the cytoplasm (~1.35-1.38) studied by F.Lanni et al. (1985) and J.Beuthan et al. (1996)
Based on these results, totally automatic non-invasive detection and segmentation of the different subcellular structures would be possible with STEVE.
In figure 1 are shown cell images with distinguishable mitochondria assembly.
1) Haseda, Keisuke, et al. “Significant correlation between refractive index and activity of mitochondria: single mitochondrion study.” Biomedical optics express 6.3 (2015): 859-869.
2) F. Lanni, A. Waggoner, D. Taylor, Internal reflection fluorescence microscopy, J. Cell Biol. 100 (1985) 1091–1102.
3) J. Beuthan, O. Minet, J. Helfman, G. Muller, The spatial variation of the refractive index in biological cells, Phys. Med. Biol. 41 (1996) 369–382.