title: Label-free proteomics reveals decreased expression of CD18 and AKNA in peripheral CD4+ T cells from patients with Vogt-Koyanagi-Harada syndrome.
abstract: Vogt-Koyanagi-Harada (VKH) syndrome is a systemic autoimmune disease. CD4(+) T cells have been shown to be involved in autoimmune diseases including VKH syndrome. To screen aberrantly expressed membrane proteins in CD4(+) T cell from patients with active VKH syndrome, blood samples were taken from five patients with active VKH syndrome and five healthy individuals. A label-free quantitative proteomic strategy was used to identify the differently expressed proteins between the two groups. The results revealed that the expression of 102 peptides was significantly altered (p<0.05) between two groups and matched amino acid sequences of proteins deposited in the international protein index (ipi.HUMAN.v3.36.fasta). The identified peptides corresponded to 64 proteins, in which 30 showed more than a 1.5-fold difference between the two groups. The decreased expression of CD18 and AKNA transcription factor (AKNA), both being three-fold lower than controls in expression identified by the label-free method, was further confirmed in an additional group of five active VKH patients and six normal individuals using the Western blot technique. A significantly decreased expression of CD18 and AKNA suggests a role for both proteins in the pathogenesis of this syndrome.
authors.affiliation: First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Ophthalmology, Chongqing Eye Institute, Chongqing, People's Republic of China. [corrected]
authors.forename: Liming
authors.initials: L
authors.lastname: Mao
authors.forename: Peizeng
authors.initials: P
authors.lastname: Yang
authors.forename: Shengping
authors.initials: S
authors.lastname: Hou
authors.forename: Fuzhen
authors.initials: F
authors.lastname: Li
authors.forename: Aize
authors.initials: A
authors.lastname: Kijlstra
mesh_terms: D000328:Adult; D000595:Amino Acid Sequence; D018821:CD18 Antigens / Q000032:analysis* / Q000096:biosynthesis; D015496:CD4-Positive T-Lymphocytes / Q000737:chemistry / Q000378:metabolism*; D016022:Case-Control Studies; D004268:DNA-Binding Proteins / Q000032:analysis* / Q000096:biosynthesis; D015536:Down-Regulation; D005260:Female; D006801:Humans; D008297:Male; D009687:Nuclear Proteins / Q000032:analysis* / Q000096:biosynthesis; D011506:Proteins / Q000032:analysis; D040901:Proteomics / Q000379:methods*; D014157:Transcription Factors / Q000032:analysis* / Q000096:biosynthesis; D014607:Uveomeningoencephalitic Syndrome / Q000209:etiology / Q000276:immunology*; D055815:Young Adult
chemical_list: C423232:AKNA protein, human; D018821:CD18 Antigens; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D011506:Proteins; D014157:Transcription Factors