06/20/2026
Every outcome in the epidermis begins with the Keratinocyte.
From hydration and barrier function to pigmentation, sensitivity, ageing and repair, the health of the epidermis is ultimately determined by the lifecycle of a single cell, the keratinocyte.
The journey begins in the stratum basale, where keratinocytes are born through mitosis. These newly formed cells gradually migrate upwards through the epidermis, undergoing a carefully orchestrated process of differentiation. As keratinocytes move through the stratum spinosum and stratum granulosum, they begin producing keratin, natural moisturising factors and the lipid components required for barrier formation. They also communicate with neighbouring cells, helping coordinate immune responses, pigmentation and epidermal repair.
By the time they reach the stratum corneum, these cells have transformed into corneocytes, flattened, highly specialised structures that form the skin's primary protective barrier. Together with the lipid matrix, they create the "brick and mortar" architecture responsible for reducing water loss, defending against environmental stressors and maintaining epidermal integrity.
When keratinocyte maturation is disrupted, the consequences are far reaching. Barrier dysfunction, increased TEWL, impaired desquamation, sensitivity, inflammation, pigmentation irregularities and delayed recovery can all follow.
This is why Corneotherapy places such importance on supporting normal epidermal function rather than simply treating symptoms. By understanding and respecting the keratinocyte lifecycle, we support the very foundation of healthy skin.