Figure 1.

Outline of the BLCC manufacturing process. (A) The fibroblast layer is formed by the deposition of a fibroblast/collagen layer on Day 0, which is incubated for 6 days to promote matrix synthesis. (B) Keratinocytes are then seeded onto the surface of the fibroblast/collagen matrix and incubated from Day 6 to Day 10 with a media change at Day 8 to allow epidermal differentiation. (C) At Day 10 after cast, the constructs are brought to the air–liquid interface to induce cornification of the epidermal layer. (D) The mature construct is ready for use at Day 20. Time points specified in the figure correlate to media changes. The red background represents media and illustrates the air lift step in which constructs are fed only from the bottom starting at Day 10. Fibroblasts and matrix are represented in blue; keratinocytes/epithelium are represented in green; and the stratum corneum is represented in yellow. Epi indicates Epidermalization, Diff indicates Differentiation, Corn indicates Cornification, Maint indicates Maintenance. BLCC, bilayered living cellular construct.