TABLE 1

Expression levels of cellular markers including those specific for keratinocytes and Langerhans cells

Identified makers for layers of the epidermis include proteins specifically expressed in the stratum spinosum, stratum granulosum, and stratum corneum. Protein identification and quantification was based on the presence of at least two unique peptides and from human skin in at least two donors. Protein expression is represented by the mean, the S.D., and the percent CV. The range of protein expression (min–max) and the number of samples (n) are also reported. Protein abundance is reported in picomoles milligram−1 of protein.

ProteinHuman SkinLabSkin 1LabSkin 2
Mean ± S.D. (CV)Range (n)Median
Keratinocyte markers
 CALML567.65 ± 16.50 (24.39)39.29–88.07 (6)72.2363.1056.92
 KRT1914.56 ± 3.99 (27.41)13.20–16.99 (6)14.364.7510.30
Langerhans cell marker
 CD2078.53 ± 0.77 (9.02)7.98–9.06 (2)8.52
Epidermis markers: stratum spinosum
 KRT104.85 ± 2.14 (44.20)1.87–8.17 (6)4.862.662.91
 CASP1416.29 ± 2.88 (17.70)11.82–18.99 (6)17.6815.1612.76
Epidermis markers: stratum granulosum
 FLG4.18 ± 1.73 (41.39)1.93–5.86 (6)4.512.801.36
Epidermis markers: stratum corneum
 KLK57.27 ± 2.86 (39.43)6.54–8.00 (2)7.272.47