The invention relates to a method for manufacturing a bio-ink by additive deposition, which comprises supplying: a first solution including between 5 and 40 wt. % gelatin; a second solution including between 15 and 35.wt. % alginate; a third solution including between 1 and 15 wt. % fibrinogen, and optionally living cells in suspension; and creating a mixture including: around 35 to 65 vol. % of the first solution; around 15 to 35 vol. % of the second solution; and around 15 to 35 vol. % of the third solution, said proportions being selected so that they add up to 100%. Said bio-ink allows the additive deposition of objects that can be polymerised by means of a solution including calcium ions and thrombin. Said objects can be incubated and can be used as a substitute for body tissue, for example (with added fibroblasts) as skin substitute.

Disclosed are bioprinted, three-dimensional, biological skin tissues comprising: a dermal layer comprising dermal fibroblasts; and an epidermal layer comprising keratinocytes, the epidermal layer in contact with the dermal layer to form the three-dimensional, engineered, biological skin tissue. Also disclosed are arrays of engineered skin tissues and methods of making engineered skin tissues.

The invention relates to biomarkers in children's skin, in particular in the skin of infants, the expression of which changes when the skin is affected by atopic dermatitis. Such markers are particularly advantageous in that they allow the skin's response to atopic dermatitis to be monitored. The inventors have developed methods for evaluating the in vitro efficacy of formulations in preventing the effects of atopic dermatitis on a child's skin, using a skin model specifically capable of reproducing the characteristics of children's skin.

Disclosed are bioprinted, three-dimensional, biological skin tissues comprising: a dermal layer comprising dermal fibroblasts; and an epidermal layer comprising keratinocytes, the epidermal layer in contact with the dermal layer to form the three-dimensional, engineered, biological skin tissue. Also disclosed are arrays of engineered skin tissues and methods of making engineered skin tissues.

The present invention relates to: a method for preparing a stem cell culture solution which contains growth factors and cytokines and is obtained by culturing, in a serum-free medium, mesenchymal stem cells cultured in a medium containing human platelet lysates (hPLs); and a cosmetic composition using the stem cell culture solution. When the method for preparing a mesenchymal stem cell culture solution obtained from mesenchymal stem cells cultured in an hPL-containing medium is used, it is possible to obtain a mesenchymal stem cell culture solution which has a higher amount of cytokines and growth factors than that of a mesenchymal stem cell culture solution obtained from mesenchymal stem cells cultured in an FBS-containing medium, and has excellent efficacy in the promotion of human dermal fibroblast proliferation, collagen synthesis, elastin synthesis, inhibition of melanin synthesis, and hair growth. The mesenchymal stem cell culture solution can be used to produce cosmetics having effects of skin regeneration, wrinkle improvement, skin elasticity enhancement, skin whitening, and hair growth, and thus can be widely used in the cosmetic field and the pharmaceutical industry.

A method of creating skin tissue is described, particularly, an in vitro or ex vivo method for creating skin tissue. The invention extends to the use of agents that disrupt the LINC complex in a skin cell to create the skin tissue, and to using the created tissue in an assay to identify or screen anti-ageing compounds. The invention further extends to model skin tissues per se, uses thereof and to kits for creating such model skin tissues.

The present invention relates to a 3D bioprinted skin tissue model, a method for providing said model and the use of said model. The 3D bioprinted skin tissue model comprises at least one bioink A, at least one cell type A, at least one factor A, wherein the bioink A comprises at least one biopolymer, a thickener, at least one extra-cellular matrix or a decellularized matrix, and optionally a photo initiator and/or cellular additions, the at least one cell type A is an epidermal, dermal and/or hypodermal cell or cell line, and the at least one factor A is a growth factor, protein and/or molecule that stimulates altered or abnormal metabolism of cell type A.

Provided is a method for constructing an atopic dermatitis skin organoid from human pluripotent stem cells. It was observed that ALI-skin organoids of the presently claimed subject matter formed skin cells, appendages, neural cells, adipocytes, and the like in similar structures to those in the real skin and exhibited greatly improved follicle growth, compared to skin organoids constructed by existing culture methods. In addition, as a result of treatment with Staphylococcus aureus to construct an atopic dermatitis model, a good simulation was made of the characteristics of atopic dermatitis, such as damaged skin barriers, increased epithelium-derived cytokines and downregulated epidermal stem cell expression, causing Staphylococcus aureus colonies, and the like. Thus, the skin organoid of the presently claimed subject matter is expected to find advantageous applications as a real skin model and an atopic dermatitis model.

The present invention relates to an in vitroprocess for preparing cell and tissue models comprising at least one step of culturing fibroblasts of the dermo-hypodermic junction; the models obtained and also the implementation thereof in processes for screening active agents that promote the differentiation of fibroblasts of the dermo-hypodermic junction into adipocyte, osteoblast and/or chondroblast cells.

Methods and compositions for simulating a dermal compartment of skin are disclosed. In one aspect of the invention, methods of producing such a skin model include the steps of admixing a collagenous protein source, a blood protein source, and dermal cells in an aqueous carrier, and then allowing the resulting mixture to solidify to produce a gel. In one technique, at least a portion of the mixture, e.g., the collagenous protein source is first heated and then cooled to induce gelation. For example, the mixture can be heated to at least 50 degrees C. and then cooled to temperature below 5 degrees C. to induce gelation.