Effect of PaCDase on ceramide, sphingosine and S1P concentration in 3D keratinocyte layers.

Nitrocellulose filters with 1 mU/ml PaCDase or 0.1% DMSO (-) in Tris-buffered saline containing 0.1% Triton X-100 were placed onto the stratum corneum. The cells were incubated for 1 h or 24 h. The keratinocyte layers were isolated, and sphingosine and S1P concentrations were measured. The concentrations of ceramide, sphingosine and S1P in the untreated keratinocyte layers are shown as 0 h. Data represent the mean±SD of 3 independent experiments.