Abstract: The invention relates to means and methods for evaluating and using the specific properties of a particular epithelial cell present in a biological sample. Accordingly, the invention relates to a system for the culture of epithelial cells, in which at least one clonal culture is sown with a single epithelial cell directly extracted from a biological sample of epithelial tissue. The invention also relates to a method for the culture of epithelial cells, that particularly comprises the production of clonal cultures, each being sown with a distinct and unique epithelial cell directly extracted from a biological sample of epithelial tissue, the evaluation of the cellular growth in the clonal cultures, and advantageously the analysis of the capacity of the cellular material from the clonal cultures to reconstruct a three-dimensional epithelium representative of native tissue.

Abstract: The invention relates to means and methods for evaluating and using the specific properties of a particular epithelial cell present in a biological sample. Accordingly, the invention relates to a system for the culture of epithelial cells, in which at least one clonal culture is sown with a single epithelial cell directly extracted from a biological sample of epithelial tissue. The invention also relates to a method for the culture of epithelial cells, that particularly comprises the production of clonal cultures, each being sown with a distinct and unique epithelial cell directly extracted from a biological sample of epithelial tissue, the evaluation of the cellular growth in the clonal cultures, and advantageously the analysis of the capacity of the cellular material from the clonal cultures to reconstruct a three-dimensional epithelium representative of native tissue.

Abstract: The enrichment of a population of keratinocyte stem cells (KSCs) from a preparation of keratinocytes and KSCs, includes pre-enrichment by contacting a sample of keratinocytes and KSCs with a collagen-coated culture plate for a sufficient time for KSCs to adhere, followed by washing away the non-adherent cells and recovering the adherent cells. The recovered adherent cells are sorted by their expression level of EGFR so that cells are recovered that have an expression level of EGFR of less than about 50% of the maximum level of EGFR expression, and the recovered cells have an expansion potential of at least 109 after about 100 days in culture.

Abstract: Leukemia Inhibitory Factor (“LIF”), an LIF analogue, an LIF mimetic and a product capable of stimulating the expression of endogenous LIF, and mixtures thereof are useful, for (i) promoting the multiplication, in vitro, of a population of human skin stem cells and/or epidermal progenitors while maintaining them in an undifferentiated state, and/or for (ii) maintaining and/or increasing their capacity to generate a pluristratified epithelium, in particular a pluristratified epidermis and/or all or some of the skin appendages; also a library or a culture of human undifferentiated skin stem cells and/or epidermal progenitors is obtained in the presence of LIF, as are reconstructed epidermides and/or reconstructed skin, and kits for producing libraries of cells or reconstructed epidermides, and stem cells or reconstructed epidermides are prepared for the treatment of individuals exhibiting damaged skin (individuals suffering from third degree burns and individuals suffering from genetic diseases affecting the ski

Abstract: Leukemia inhibitory factor (“LIF”), an LIF analogue, an LIF mimetic, a product capable of stimulating the expression of endogenous LIF and mixtures thereof are useful for maintaining and/or stimulating the regenerative power of a population of human undifferentiated skin stem cells and/or epidermal progenitors, and are also useful for treating dry and/or chapped and/or aged skin and/or hair loss, as well as for treating skin burns and promoting skin regeneration and/or cicatrization.

Abstract: The invention concerns a method for enriching a population of keratinocyte stem cells, from a preparation of keratinocytes, comprising a pre-enrichment step in keratinocyte stem cells by adherence of said preparation on a constituent of extra-cellular matrices, in particular recognized by molecules involved in the adherence of the keratinocytes, in particular by the integrin family receptors, particularly collagen, for a period of time between about 5 and about 30 minutes, preferably between about 10 and about 20 minutes, advantageously 12 minutes, and in recuperating the stem cells which have adhered on said constituent of extra-cellular matrices by separation in conditions enabling to maintain the viabilty of the stem cells which have adhered, in particular by trypsinization, particularly using trypsin 0.05% and EDTA 0.02% to obtain a population of adherent cells.