Table II. Extracellular space proteins identified by proteomics in three guanidine extracts.
IGF, insulin-like growth factor.
| Protein name | Swiss-Prot accession name | Molecular mass | Unique peptides, n | Unique spectra, n | Coverage | Total spectra,an |
|---|---|---|---|---|---|---|
| kDa | % | |||||
| Proteoglycans and glycoproteins | ||||||
| Perlecan | PGBM_HUMAN | 469 | 367 | 481 | 19.0 | 1596 |
| Fibronectin | FINC_HUMAN | 263 | 182 | 218 | 20.0 | 1028 |
| Versican | CSPG2_HUMAN | 373 | 76 | 89 | 4.4 | 681 |
| Aggrecan | PGCA_HUMAN | 250 | 70 | 82 | 6.3 | 451 |
| Biglycan | PGS1_HUMAN | 42 | 56 | 62 | 36.0 | 352 |
| Lactadherin | MFGM_HUMAN | 43 | 64 | 67 | 48.0 | 309 |
| Prolargin | PRELP_HUMAN | 44 | 55 | 78 | 37.0 | 283 |
| Periostin | POSTN_HUMAN | 93 | 100 | 117 | 29.0 | 257 |
| Lumican | LUM_HUMAN | 38 | 53 | 58 | 30.0 | 204 |
| Decorin | PGS2_HUMAN | 40 | 43 | 51 | 29.0 | 173 |
| Clusterin | CLUS_HUMAN | 52 | 44 | 48 | 23.0 | 173 |
| Tenascin-X | TENX_HUMAN | 464 | 79 | 79 | 4.5 | 140 |
| Laminin subunit γ-1 | LAMC1_HUMAN | 178 | 40 | 44 | 18.0 | 129 |
| Link protein 1 | HPLN1_HUMAN | 40 | 26 | 29 | 33.0 | 117 |
| Laminin subunit β-2 | LAMB2_HUMAN | 196 | 34 | 34 | 14.0 | 104 |
| Vitronectin | VTNC_HUMAN | 54 | 25 | 27 | 14.0 | 102 |
| Nidogen-1 | NID1_HUMAN | 136 | 56 | 64 | 15.0 | 101 |
| Adipocyte enhancer-binding protein 1b | AEBP1_HUMAN | 131 | 34 | 40 | 7.6 | 94 |
| Laminin subunit α-5 | LAMA5_HUMAN | 400 | 39 | 39 | 4.6 | 91 |
| Tenascin | TENA_HUMAN | 241 | 25 | 25 | 5.6 | 52 |
| Mimecan | MIME_HUMAN | 34 | 21 | 21 | 15.0 | 48 |
| EGF-containing fibulin-like ECM protein 1 | FBLN3_HUMAN | 55 | 22 | 24 | 15.0 | 48 |
| Fibulin-5 | FBLN5_HUMAN | 50 | 17 | 17 | 14.0 | 40 |
| Galectin-1 | LEG1_HUMAN | 15 | 17 | 20 | 53.0 | 40 |
| TGFβ-induced protein ig-h3 | BGH3_HUMAN | 75 | 23 | 23 | 12.0 | 35 |
| EMILIN-1 | EMIL1_HUMAN | 107 | 8 | 8 | 3.0 | 30 |
| Fibulin-1 | FBLN1_HUMAN | 77 | 17 | 17 | 12.0 | 29 |
| Latent TGFβ-binding protein 2b | LTBP2_HUMAN | 195 | 13 | 13 | 2.7 | 22 |
| Fibromodulin | FMOD_HUMAN | 43 | 8 | 11 | 8.2 | 22 |
| Microfibril-associated glycoprotein 4 | MFAP4_HUMAN | 29 | 8 | 8 | 12.0 | 21 |
| Dermatopontin | DERM_HUMAN | 24 | 8 | 9 | 12.0 | 21 |
| Fibrillin-1 | FBN1_HUMAN | 312 | 15 | 15 | 2.4 | 21 |
| Latent TGFβ-binding protein 4b | LTBP4_HUMAN | 173 | 12 | 12 | 4.2 | 15 |
| Nidogen-2 | NID2_HUMAN | 151 | 8 | 8 | 3.5 | 11 |
| Agrinb | AGRIN_HUMAN | 215 | 7 | 7 | 2.3 | 11 |
| Asporin | ASPN_HUMAN | 43 | 8 | 8 | 11.0 | 11 |
| Cartilage oligomeric matrix protein | COMP_HUMAN | 83 | 4 | 4 | 3.6 | 7 |
| Thrombospondin-1 | TSP1_HUMAN | 129 | 3 | 3 | 1.8 | 7 |
| Matrix Gla protein | MGP_HUMAN | 12 | 4 | 4 | 13.0 | 6 |
| Galectin-3 | LEG3_HUMAN | 26 | 2 | 2 | 6.0 | 4 |
| Sclerostinb | SOST_HUMAN | 24 | 2 | 2 | 5.6 | 3 |
| Matrilin-2b | MATN2_HUMAN | 107 | 2 | 2 | 2.3 | 3 |
| Other ECM-associated proteins | ||||||
| Serum amyloid P-component | SAMP_HUMAN | 25 | 32 | 33 | 33.0 | 169 |
| Tubulointerstitial nephritis antigen-likeb | TINAL_HUMAN | 52 | 46 | 55 | 21.0 | 131 |
| Extracellular superoxide dismutase | SODE_HUMAN | 26 | 28 | 35 | 25.0 | 102 |
| Target of Nesh-SH3b | TARSH_HUMAN | 119 | 30 | 33 | 8.6 | 89 |
| IGF-binding protein 7b | IBP7_HUMAN | 29 | 30 | 31 | 28.0 | 59 |
| Cysteine-rich protein 2 | CRIP2_HUMAN | 22 | 20 | 21 | 25.0 | 57 |
| TGFβ-1-induced transcript 1 proteinb | TGFI1_HUMAN | 50 | 27 | 27 | 45 | |
| LIM and cysteine-rich domains protein 1b | LMCD1_HUMAN | 41 | 25 | 25 | 34.0 | 39 |
| Apolipoprotein Hb | APOH_HUMAN | 38 | 10 | 12 | 9.0 | 32 |
| Galectin-3-binding protein | LG3BP_HUMAN | 65 | 12 | 12 | 12.0 | 23 |
| RPE-spondinb | RPESP_HUMAN | 30 | 12 | 12 | 22.0 | 19 |
| kDa | % | |||||
| Carboxypeptidase-like protein X2b | CPXM2_HUMAN | 86 | 9 | 11 | 7.3 | 16 |
| Latent TGFβ-binding protein, isoform 1Sb | LTB1S_HUMAN | 153 | 8 | 9 | 2.7 | 13 |
| Pigment epithelium derived factor | PEDF_HUMAN | 46 | 5 | 5 | 8.6 | 8 |
| Secreted frizzled-related protein 1b | SFRP1_HUMAN | 35 | 3 | 3 | 8.9 | 6 |
| Properdinb | PROP_HUMAN | 51 | 3 | 4 | 5.1 | 5 |
| Spondin-1b | SPON1_HUMAN | 91 | 3 | 3 | 3.0 | 4 |
| Neutrophil defensin 1b | DEF1_HUMAN | 10 | 2 | 2 | 9.6 | 4 |
| Proteases and protease inhibitors | ||||||
| Serine protease HTRA1 | HTRA1_HUMAN | 51 | 22 | 22 | 13.0 | 68 |
| Chymaseb | CMA1_HUMAN | 27 | 12 | 15 | 11.0 | 23 |
| Lysyl oxidase homolog 1b | LOXL1_HUMAN | 63 | 12 | 12 | 7.3 | 23 |
| Metalloproteinase inhibitor 3 | TIMP3_HUMAN | 24 | 9 | 9 | 17.0 | 12 |
| Tryptase β-1b | TRYB1_HUMAN | 31 | 6 | 7 | 9.8 | 11 |
| Procollagen C-endopeptidase enhancer 1 | PCOC1_HUMAN | 48 | 7 | 7 | 6.7 | 10 |
| Cathepsin Gb | CATG_HUMAN | 29 | 7 | 7 | 15.0 | 8 |
| Cathepsin D | CATD_HUMAN | 45 | 4 | 4 | 2.7 | 7 |
| Antileukoproteinaseb | SLPI_HUMAN | 14 | 3 | 3 | 9.1 | 6 |
| Myeloblastinb | PRTN3_HUMAN | 28 | 2 | 2 | 4.7 | 4 |
| Collagens | ||||||
| Collagen α-3(VI) | CO6A3_HUMAN | 344 | 164 | 186 | 20.0 | 898 |
| Collagen α-1(XIV)b | COEA1_HUMAN | 194 | 136 | 150 | 20.0 | 529 |
| Collagen α-1(XVIII) | COIA1_HUMAN | 178 | 45 | 48 | 5.9 | 374 |
| Collagen α-1(VI) | CO6A1_HUMAN | 109 | 50 | 71 | 16.0 | 282 |
| Collagen α-2(VI) | CO6A2_HUMAN | 109 | 31 | 31 | 19.0 | 155 |
| Collagen α-2(IV) | CO4A2_HUMAN | 168 | 26 | 31 | 3.9 | 139 |
| Collagen α-1(XV) | COFA1_HUMAN | 142 | 32 | 34 | 7.5 | 100 |
| Collagen α-1(XII) | COCA1_HUMAN | 333 | 42 | 42 | 4.0 | 90 |
| Collagen α-2(I) | CO1A2_HUMAN | 129 | 12 | 15 | 3.5 | 70 |
| Collagen α-1(I) | CO1A1_HUMAN | 139 | 14 | 15 | 5.9 | 51 |
| Collagen α-1(VIII) | CO8A1_HUMAN | 73 | 5 | 5 | 1.3 | 33 |
| Collagen α-1(V) | CO5A1_HUMAN | 184 | 6 | 6 | 0.6 | 23 |
| Collagen α-2(VIII) | CO8A2_HUMAN | 67 | 4 | 4 | 3.3 | 9 |
| Collagen α-1(IV) | CO4A1_HUMAN | 161 | 5 | 5 | 1.8 | 8 |
a Sum of all spectra identified for each protein in the three biological samples, performed with two technical replicates each.
b Proteins found for the first time by proteomics in the vasculature.