TABLE 6

Expression levels of proteases, nucleases, and protease inhibitors in human skin and LabSkin

Protein identification and quantification was based on the presence of at least two different peptides and from human skin of at least two donors. Protein expression is represented by the mean, the S.D. of the mean (S.D.), the percent CV, the range (min–max), and the number of samples (n). Protein abundance is reported in picomole milligram−1 of protein.

ProteinHuman SkinLabSkin 1LabSkin 2
Mean ± S.D. (CV)Range (n)Median
Aminopeptidases
 ANPEPa13.03 ± 10.09 (77.39)5.48–27.33 (4)9.6622.74
 DNPEP9.93 ± 2.47 (24.83)7.10–11.58 (3)11.121.51
 ERAP14.63 ± 1.09 (23.55)2.91–5.88 (6) (3)4.925.353.36
 LAP310.14 ± 4.56 (44.94)4.59–16.93 (6)9.776.955.36
 LNPEP6.42 ± 2.40 (37.42)4.72–8.12 (2)6.42
 METAP13.10 ± 0.66 (21.19)2.63–3.56 (2)3.109.241.68
 NPEPPSa7.99 ± 1.51 (18.92)5.91–9.61 (6)8.059.515.76
 RNPEP19.51 ± 28.19 (144.45)5.60–76.85 (6)8.5442.0171.51
 XPNPEP13.90 ± 1.70 (43.57)2.40–6.32 (4)3.445.41
 XPNPEP38.34 ± 0.50 (5.99)7.77–8.67 (3)8.585.38
Endopeptidases
 ASPRV111.12 ± 2.94 (26.47)6.18–14.54 (6)11.2630.147.58
 CAPN112.54 ± 2.14 (17.04)10.63–15.72 (6)11.8512.619.86
 CAPN29.99 ± 2.57 (25.73)5.94–12.85 (5)10.425.458.25
 FAP4.50 ± 1.44 (31.93)2.93–5.76 (3)4.805.14
 PREP6.28 ± 1.76 (28.06)4.51–8.83 (6)5.895.153.64
Peptidases/proteases
 CNDP211.59 ± 3.45 (29.76)5.16–15.59 (6)12.175.458.23
 DPP34.94 ± 1.88 (38.15)2.98–8.06 (5)4.595.693.61
 DPP4a4.80 ± 2.00 (41.63)2.99–7.65 (4)4.286.17
 DPP72.81 ± 1.78 (63.27)1.55–4.06 (2)2.813.30
 LONP14.51 ± 0.99 (21.85)3.40–5.29 (3)4.855.701.95
 PEPD6.22 ± 1.85 (29.75)3.78–8.71 (6)6.453.815.21
 TPP110.57 ± 2.27 (21.50)7.48–13.66 (5)10.5212.085.66
 CTSA5.26 ± 2.30 (43.64)2.28–8.60 (5)4.7514.373.06
 CTSB8.95 ± 2.56 (28.54)4.49–11.53 (6)9.709.275.03
 CTSC7.72 ± 4.41 (57.13)5.41–15.59 (5)5.8420.442.73
 CTSD24.35 ± 6.18 (25.38)17.65–32.76 (6)23.5919.1211.39
 CTSGb9.50 ± 6.73 (70.84)4.74–14.26 (2)9.502.51
 CTSZ8.06 ± 3.12 (38.75)4.25–12.62 (5)8.2716.803.60
 DCDc30.98 ± 20.58 (66.44)10.73–60.60 (5)20.734.5349.02
 BLMH7.08 ± 2.22 (31.36)5.75–9.65 (3)5.86
Metalloproteases
 ADAM103.13 ± 0.55 (17.46)2.75–3.52 (2)3.13
 MMP2a4.99 ± 5.49 (110.16)1.10–8.87 (2)4.998.08
Carboxypeptidases
 CPA3a9.56 ± 4.67 (48.82)4.59–15.00 (4)9.33
 CPB2b5.63 ± 1.79 (31.83)2.91–7.90 (5)5.922.98
 CPMa3.89 ± 1.60 (41.09)2.76–5.02 (2)3.89
 CPN1b10.13 ± 2.23 (21.98)8.56–11.71 (2)10.13
 CPN2b6.93 ± 1.36 (19.60)4.66–8.11 (5)7.132.45
 CPQa3.92 ± 1.04 (26.49)2.69–5.38 (5)4.074.632.28
 CPVLa2.85 ± 0.92 (32.30)1.98–3.82 (3)2.75
 PRCP4.79 ± 2.27 (47.45)2.97–9.20 (6)4.1310.76
Nucleases
 ENDOD14.57 ± 2.66 (58.22)2.18–7.48 (4)4.304.08
 RNASE1a9.46 ± 1.79 (18.87)7.54–11.64 (5)8.80
 RNASE4a3.78 ± 1.98 (52.39)1.41–6.22 (4)3.743.14
 RNASET26.57 ± 1.39 (21.14)4.58–7.65 (4)7.035.55
 SND13.43 ± 2.35 (68.57)1.38–7.44 (5)2.799.25
 TATDN15.55 ± 2.21 (39.73)2.54–7.49 (4)6.09
 YBX1d2.73 ± 1.43 (52.45)1.22–4.50 (4)2.605.55
Peptidase/protease inhibitors
 CST39.88 ± 3.61 (36.54)6.07–14.71 (5)9.5818.396.21
 CST68.66 ± 3.01 (34.80)5.58–12.82 (5)8.42
 CSTA9.24 ± 5.47 (59.24)5.37–13.10 (2)9.2415.59
 CSTB42.93 ± 22.3 (52.0)25.65–82.24 (6)34.0138.0737.26
 PI168.74 ± 2.83 (32.37)5.61–13.24 (5)7.844.24
 SERPING1a24.68 ± 6.61 (26.79)13.15–29.79 (5)26.393.2613.21
 SPINK57.06 ± 2.02 (28.64)5.63–8.49 (2)7.063.96
Proteosome
 PSMC16.89 ± 1.04 (15.02)6.16–7.62 (2)6.891.82
 PSMC22.61 ± 0.96 (36.79)1.24–3.42 (4)2.884.251.78
 PSMC35.22 ± 1.45 (27.83)3.38–7.74 (6)5.025.863.24
 PSMC52.95 ± 0.86 (29.03)1.69–3.59 (4)3.264.41
 PSMC63.80 ± 1.09 (28.76)2.82–5.53 (5)3.546.661.99
Ribonuclease inhibitor
 RNH122.47 ± 5.55 (24.71)12.60–25.88 (5)24.3421.6517.56
  • DCD, dermicidin; SERPING1, plasma protease C1 inhibitor

  • a According to Human Protein Atlas, these enzymes are reported to be present in the skin at the RNA level (low copy numbers) but not at the protein level.

  • b According to Human Protein Atlas, these enzymes are not reported to be present in the skin at the RNA or protein level.

  • c Also displays antimicrobial activity, thereby limiting skin infection by potential pathogens in the first few hours after bacterial colonization.

  • d YBX1 can promote the expression of multidrug resistance 1 gene, which is involved in the development of drug resistance.