title: Effect of cytotoxic T lymphocyte-associated molecule 4 1661 gene polymorphism on its expression and transcription in ulcerative colitis.
abstract: OBJECTIVE
  Our aim was to investigate the expression of cytotoxic T lymphocyte-associated molecule 4 (CTLA-4) in ulcerative colitis (UC) and to evaluate the effect of CTLA-4 gene -1661A/G polymorphism on CTLA-4 expression and transcription.
  
  
  METHODS
  A total of 20 UC patients and 22 healthy controls matched by age and sex were enrolled at Zhongnan Hospital of Wuhan University in central China. The CTLA-4 -1661A/G polymorphism was genotyped by the polymerase chain reaction-restriction fragment length polymorphism method. A Western blot analysis was performed to determine the full length CTLA-4 (flCTLA-4) protein expression in the peripheral blood of the UC patients. Serum-soluble CTLA-4 (sCTLA-4) levels were measured by enzyme-linked immunosorbent assay. CTLA-4-1661G mutant promoter transcription function was analyzed by site-directed PCR-based mutagenesis.
  
  
  RESULTS
  CTLA-4 protein expression on CD4(+) T cells in UC patients was lower than that in the healthy controls (P < 0.001) while serum sCTLA-4 in the UC patients was significantly higher than that in the healthy controls (P < 0.001). No correlation was found between flCTLA-4 and sCTLA-4 expression levels and the -1661 A/G polymorphism of the CTLA-4 gene. Meanwhile, CTLA-4 -1661 allele A had no significant impact on the promoter activity compared with allele G (P > 0.05).
  
  
  CONCLUSIONS
  CTLA-4 expressions were aberrant in UC patients compared with the healthy controls. CTLA-4 -1661A/G polymorphism had no significant impact on CTLA-4 expression and transcription in the peripheral CD4 T cells of UC patients.
authors.affiliation: Department of Gastroenterology, Zhongnan Hospital of Wuhan University, Wuhan, Hubei Province, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Jiang
authors.forename: Liu Qing
authors.initials: LQ
authors.lastname: Ge
authors.forename: Zhi Tao
authors.initials: ZT
authors.lastname: Chen
authors.forename: Chun
authors.initials: C
authors.lastname: Li
authors.forename: Feng
authors.initials: F
authors.lastname: Zhou
authors.forename: Yan
authors.initials: Y
authors.lastname: Luo
authors.forename: Bing
authors.initials: B
authors.lastname: Xia
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015703:Antigens, CD / Q000235:genetics* / Q000378:metabolism; D060908:CTLA-4 Antigen; D002478:Cells, Cultured; D003093:Colitis, Ulcerative / Q000235:genetics* / Q000276:immunology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017354:Point Mutation; D011110:Polymorphism, Genetic; D011401:Promoter Regions, Genetic / Q000502:physiology; D013602:T-Lymphocytes, Cytotoxic / Q000166:cytology / Q000276:immunology* / Q000378:metabolism; D014158:Transcription, Genetic / Q000276:immunology; D055815:Young Adult
chemical_list: D015703:Antigens, CD; D060908:CTLA-4 Antigen; C556706:CTLA4 protein, human