614 Modulation of NK cell activation by calcium from alginate dressings in vitro

Early after skin wounds, innate immune cells, including natural killer (NK) infiltrate the wound bed within first 24 hours. The application of widely used calcium alginate dressings facilitates cutaneous healing by releasing Ca2+ ions into exudate and locally enriching its level. Since have been identified as one main activators NK functions, effects two dressings, Algosteril® (Algo, pure alginate) Biatain® Alginate (BIA, with CMC), CaCl2 solution were compared on cell cytotoxicity analyzing K562 lysis CD107a expression well their IFN-γ TNF-α production. cells isolated from healthy donor blood incubated during 18h a 3mM or conditioned media (CM) prepared according to ISO 10-993 standard. Our results showed that dressing Algo-CM, but not BIA-CM, significantly enhanced capacity kill targets. Algo-CM increased activation degranulation cytotoxic CD56dim shown expression. TNF-a production was be mediated Ca2+-independent mechanism. Extracellular influx also induced in response Algo, suggesting role for permeable plasma membrane channels. Altogether, present data enhances activity. This underlined mode action this medical device defense through functions released Ca2+. They highlighted non-equivalence between activities.