Autofluorescence properties of murine embryonic stem cells during spontaneous differentiation phases

Abstract

These data open promising perspectives for the monitoring of stem cells differentiation under living conditions without labeling with exogenous agents (inducing perturbations when used in vivo), or immunomarkers not always available for veterinary and zootechnics, by exploiting endogenous fluorophores as intrinsic biomarkers of cell morphofunctional changes.

Autofluorescence spectroscopy and imaging: a tool for biomedical research and diagnosis

“…The presence of lipofuscins is inversely correlated with the differentiation degree in stem cells. 44 , 55 , 113 This phenomenon has been ascribed to autophagic processes actively engaged in the removal and oxidation of undesired subcellular structures, with particular reference to mitochondria. Regulating the number of mitochondria would preserve the prevailing anaerobic energetic metabolism of stem cells, thus contributing to the stemness maintenance.…”

Lipofuscin, lipofuscin-like pigments and autofluorescence

“… 4 , 5 During ageing, for instance, lipofuscin accumulation may be physiologically observed in the liver as well as in the central nervous system, at the level of which the occurrence of lipofuscin, lipofuscin-like lipopigments and ceroid may be also detected during oxidative stress, or as a response to given lysosomal storage diseases (Batten disease or neuronal ceroid lipofuscinosis ) 6 and to a number of physical and chemical noxae , such as radiation, cisplatin, lead (Pb) and mercury (methyl-Hg), under both natural and experimental disease conditions. 1 , 7-10 Moreover, lipofuscin and lipofuscin-like substances, which alongside with their well known AF properties 1 , 11 may be easily demonstrated in host cells by means of Schmorl and/or Sudan Black histochemical stains, 10 , 12 , 13 have been reported to increase in human mesenchymal stem cells subjected to oxidative stress, 14 while decreasing in murine embryonic stem cells undergoing differentiation, 15 a finding that might be of relevance also in relation to the recently described epithelial CSC-specific AF. 2 Beside what above, lipofuscin bodies may be observed in a number of additional pathologic conditions, both neoplastic and non-neoplastic, such as pancreatic tumours, non-choroidal melanomas, mammary gland carcinomas, pigmented eyelid cysts, retinal degenerative processes like age-related macular degeneration and brown bowel syndrome or intestinal lipofuscinosis.…”

New light in flavin autofluorescence

“…8 , 20-25 The combined AF analysis of these two endogenous fluorophores was thus at the basis of remarkable experimental investigations and applications in biomedicine for the in situ assessment and real time monitoring of organ or cell functionality, 26-30 providing direct information on cell and tissue response ability to external stimuli or on cell intrinsic features, such as stemness degree and cancer transformation. 6 , 22 , 31-35 …”