THE INNER EAR OF SEVEN DAYS OLD MICE CONTAINES PLURIPOTENT STEM CELLS

The purpose of the ongoing research is to improve our current skills and knowledge instem cell isolation, cultivation and differentiation from the utricular and saccularepithelia of young mice. We harvested utricles and sacculi from 7 days old NMRI mice.Utricles were trypsinized in order to isolate single cells. Obtained cells were cultivatedin DMEM with F12 Nutrient mixture, B27, N2 supplement, IGF-1 and EGF. Spherepluripotency was established with stem cell markers Nanog and Oct-4. We mechanicallydissociated primary spheres and cultivated. Secondary spheres were placed onfibronectin coated tissue culture slide chambers in the absence of IGF-1 and EGF. Cellswere characterized by immunofluorescence and immunohistochemistry for myosinVIIA(hair cell marker) and nestin (intermediate filament VI marker). Vestibular epitheliacontain pluripotent stem cells able to form cell clusters (spheres). Pluripotency wasdemonstrated by the expression of nanog, oct 4 and nestin markers (cell progenitors).Also sphere dissociation and separate cultivation of the isolated cells lead to theformation of larger spheres and in higher amounts compared to the original spheres,proving that these cells are not only pluripotent but also capable of self-renewal. Singlespheres harvested and cultivated on fibronectin produced through differentiationdifferent cell types including neuron like-cells, positive for myosin VIIA and nestin.