Sprayed keratinocyte suspensions accelerate epidermal coverage in a porcine microwound model

Keratinocyte suspensions can potentially treat a variety of epidermal defects, but the mechanism of action has not been fully determined. We developed a porcine model to study the effect of sprayed cell suspensions delivered on small wounds within a meshed autograft. Paired full-thickness surgically excised wounds were covered with a fully expanded 3:1 meshed split-thickness autograft. A keratinocyte cell suspension was sprayed onto half of the wounds at a seeding density of 2.8 x 10(3) cells/cm2; the remaining wounds were sprayed with cell culture medium alone. Histologic analysis at days 5 and 8 showed an increase in average epidermal thickness, confluence, keratin cysts, and blood vessels in the keratinocyte cell suspension group compared with the cell culture medium control group. Wounds sprayed with the cell suspension showed faster and better quality of epithelialization than wounds sprayed with cell culture medium alone.