title: Association of CTLA-4 gene microsatellite polymorphism with ulcerative colitis in Chinese patients.
abstract: Ulcerative colitis (UC) is characterized by chronic intestinal inflammation as a result of an exaggerated T cell response. Cytotoxic T lymphocyte associated antigen-4 (CTLA-4), expressed mainly in activated T cells, inhibits T cell activation and proliferation by combining B7 through competing CD28 and maintains immune homeostasis. Polymorphisms of the CTLA-4 gene are known to be associated with several autoimmune diseases. The aim of this study was to investigate the association between the CTLA-4 gene microsatellite polymorphism and UC in Chinese patients. Unrelated 100 Chinese patients with UC and 140 healthy controls were studied. The (AT) repeats in the 3' untranslated region of exon 4 of the CTLA-4 gene were amplified by allele-specific polymerase chain reaction (PCR). The amplified products were electrophoresed on a 12% polyacrylamide gel, followed by silver staining. Twenty alleles were found in Chinese patients and healthy controls. The 122-bp allele was increased in UC compared with healthy controls (9.5% vs 0.7%, P = 0.0001/Pc = 0.002, OR = 14.591, 95%CI 3.357-63.420). The frequency of the longer alleles (>or=118 bp) of UC was higher than that in healthy controls (26% vs 4%, P = 0.0001/Pc = 0.0002, OR = 7.644, 95%CI 3.950-14.792), but was not associated with location and severity of the disease. Furthermore, the longer alleles were not associated with haplotypes of C-318T/A+49G of the CTLA-4 gene in Chinese patients with UC. The longer alleles of the CTLA-4 gene microsatellite polymorphism were strongly associated with UC in Chinese patients.
authors: Department of Internal Medicine & Geriatrics, Research Center of Digestive Diseases, Zhongnan Hospital, Key Laboratory of Allergy and Immune-related Diseases, Wuhan University School of Medicine, Wuhan, China.
authors: Yi
authors: Y
authors: Jiang
authors: Bing
authors: B
authors: Xia
authors: Li
authors: L
authors: Jiang
authors: Min
authors: M
authors: Lv
authors: Qiusha
authors: Q
authors: Guo
authors: Min
authors: M
authors: Chen
authors: Jin
authors: J
authors: Li
authors: Harry Hua-Xiang
authors: HH
authors: Xia
authors: Benjamin Chun-Yu
authors: BC
authors: Wong