As 2D cultures as well as animal models do have their restrictions concerning predictability of human response, we aim to establish a melanoma skin model to study metastasis and possible anti-melanoma therapies in vitro.
Our full-thickness skin equivalents (FTSE) comprise the dermis and the epidermis. For the dermal part, primary human dermal fibroblasts are cast in collagen type I hydrogel which is subsequently plastic compressed. After some days to allow the fibroblasts to remodel the hydrogel, the epidermal part is built up by seeding primary human keratinocytes together with melanoma cells onto the dermis. The next day the models are set to the air-liquid interface for up to 21 days during which the keratinocytes differentiate and the models mature. To study metastasis and possible interactions with the vascular system, endothelial cells are incorporated into the dermal part of the models. By casting a channel into the hydrogel which is subsequently seeded with endothelial cells we generated a central vessel for perfusion of the model. Additional endothelial cells were seeded into the gel to form a capillary network which is intended to connect to the central vessel.
We were able to integrate different melanoma cell lines in recombinant human epidermis (RHE) as well as in FTSE. Melanoma in FTSE were smaller than in RHE, therefore we want to investigate whether the dermal part and especially the fibroblasts have a suppressive effect. Furthermore, with the melanoma cells incorporated into our models we want to assess the efficacy of anti-melanoma therapies. For studying interactions between melanoma and the vascular system we integrated endothelial cells into our models. They are able to sprout in our models and therefore form rudimentary networks. By connecting them to the central vessel we hope to generate a perfusable vascular system. In the future, metastasis of melanoma and possible treatments shall be investigated with these models.

Melanoma skin equivalents for studying metastasis and anti-melanoma therapies