FV 969. Transplantation Surgery Used Autologous Transgenic Keratinocyte Cultures Which Regenerated an Entire, Fully Functional Epidermis

Background: Generalized junctional epidermolysis bullosa is a hereditary, often lethal genetic disease characterized by the development of blisters, skin erosion, or chronic wounds in response to minor trauma. Motor impairment or motor developmental delay accompanies the clinical manifestation of this noncurable disease. About 40% of all juvenile patients suffering from JEB die before adolescence.1 In 2015, a team of researchers of the Ruhr-University Bochum and the University of Modena, however, succeeded in restoring the epidermis in a 7-year-old boy who suffered from complete and life-threatening epidermal loss of ∼80% of total body surface areas. Transplantation surgery used autologous transgenic keratinocyte cultures which regenerated an entire, fully functional epidermis. To date, this epidermis remains resistant to mechanical stress. A postoperative quantitative sensory testing showed normative perception thresholds, indicating preserved peripheral sensory processing by intact functioning of the C-, α-, and Aβ fibers. It remains to be clarified however, if all aspects of somatosensory processing, in particular those mediated by central processes, are “fully functional.” This issue is of particular interest, as it addresses the question whether an epidermis regenerated by genetically modified stem cells reinstates full afferent neuron, cell, and receptor function, that is, functioning beyond the relay of peripheral signals to an intact processing and integration of tactile and proprioceptive stimuli into a neuronal body representation in the primary somatosensory cortex. This aspect of the neuronal body representation mediates perception and location of stimuli associated with the sensation of touch, itch, or pain on the body (somatoperception) and is crucial for motor planning, coordinated movement in space and bodily self-perception.2