In response to exogenous stimuli such as non-sensitizing contact irritants, human keratinocytes produce various types of soluble pro-inflammatory mediators including prostaglandin E-2 (PGE(2)) and interleukin 8 (IL-8). Polyunsaturated fatty acids of the n - 3 series (n - 3 PUFA) are known to play a role in the prevention of the inflammatory response. In this work, n - 3 PUFA were supplied to keratinocytes through Marinosomes (R) that are liposomes based on a natural marine lipid extract. Marinosomes (R) contributed to reduce inflammation induced by croton oil by regulating PGE2 and IL-8 production in human keratinocyte cultures. However, the preventing effect of Marinosomes (R) was highly dependent on the lipid concentration used and the liposome mean diameter. (C) 2007 Elsevier B.V. All rights reserved.