Differentiation of equine induced pluripotent stem cells into a keratinocyte lineage.

This study aimed to develop an efficient method to transform equine induced pluripotent stem cells (eiPSC) into keratinocytes, a type of skin cell important for healing wounds. The results showed successful differentiation with characteristics promising for the creation of a stem cell-based skin construct that could potentially regenerate lost or damaged skin.

Context and Purpose

• The research is based on the problem of skin trauma in horses, which often results in chronic nonhealing wounds. The healing process typically struggles due to a lack of keratinocyte cover, a crucial element for active and efficient healing.
• The paper emphasizes the importance of keratinocytes, which have the capability of self-renewal and differentiation – features crucial to skin homeostasis and repair.
• Given the potential to generate functional keratinocytes from iPSC in mice and men, the team hypothesised that similar differentiation in horses can contribute extensively to advancements in veterinary regenerative medicine.

Methodology

• The researchers carried out an experimental in vitro study using equine iPSC, established using a nonviral system, and treated for 30 days with retinoic acid and bone morphogenetic protein-4 to induce differentiation into iPSC-KC.
• To assess the effectiveness of the differentiation, the researchers measured temporospatial gene and protein expression by eiPSC-KC at weekly intervals and in response to a calcium switch.
• The team compared the proliferative and migratory capacities of the resulting eiPSC-KC with primary equine keratinocytes (PEK).

Key Findings

• The researchers observed a loss of pluripotency genes in the eiPSC and a progressive increase in pancytokeratin expression, indicating ectodermal specification into keratinocytes.
• High differentiation efficiency was found, with 82.5% of eiPSC expressing keratin 14, a marker of epidermal-specific basal stem cells, after 30 days of directed differentiation.
• Interestingly, the study found the proliferative capacity of eiPSC-KC to be superior, while the migratory capacity was comparable with that of PEK.
• The results provide proof of concept that eiPSC can effectively produce equine keratinocytes (eiPSC-KC) with features promising for developing stem cell-based skin constructs potentially useful for treating damaged or lost skin.