Wu Chih-Te, Eiserich Jason P, Ansari Aftab A, Coppel Ross L, Balasubramanian Sripriya, Bowlus Christopher L, Gershwin M Eric, Van De Water Judy
Division of Rheumatology, Allergy and Clinical Immunology, School of Medicine, University of California at Davis, TB 192, Davis, CA 95616, USA.
Hepatology. 2003 Oct;38(4):1018-25. doi: 10.1053/jhep.2003.50407.
Previous studies have suggested that increased nitric oxide (NO)-mediated products are found in the livers of subjects with primary biliary cirrhosis (PBC), but the mechanisms involved remain enigmatic. We took advantage of immunohistochemistry and several unique monoclonal antibodies to study inflammatory cells responsible for the generation of NO, the enzymes responsible for NO production, the expression of 3-nitrotyrosine, and the presence of CD68(+) and/or myeloperoxidase (MPO)(+) cells. We examined a total of 113 liver specimens, including 64 with PBC, 19 with primary sclerosing cholangitis (PSC), 6 with non-A, non-B hepatitis, 6 with alcoholic liver disease, 4 with cryptogenic cirrhosis, 4 with biliary atresia, and 10 normal subjects. Twenty-two percent of PBC had elevated expression of 3-nitrotyrosine in their bile duct epithelial cells (BECs) (P =.0316). Furthermore, the BECs in PBC also demonstrated apoptotic changes. MPO-positive inflammatory cells were also noted adjacent to the basement membrane. In contrast, the liver of normal subjects showed few apoptotic changes in the bile ducts, with no evidence of MPO staining in the portal area. Furthermore, sections from livers of subjects with stage I or stage II PBC demonstrated significantly increased inflammatory cell infiltration (P =.0064) and elevated 3-nitrotyrosine expression in BECs (P =.0246) compared with stage III and IV. The presence of 3-nitrotyrosine was closely associated with infiltrating CD68- and/or MPO-positive cells. There was also a stage-associated difference in the presence of bile duct infiltrating cells and 3-nitrotyrosine in PBC with an increase dominant in early stage disease. In conclusion, NO and reactive oxygen species, collectively determined as 3-nitrotyrosine, are associated with bile duct destruction in PBC and are particularly prevalent in early stage disease.
以往研究表明，原发性胆汁性肝硬化（PBC）患者肝脏中一氧化氮（NO）介导产物增多，但相关机制仍不清楚。我们利用免疫组织化学和几种独特的单克隆抗体，研究产生NO的炎症细胞、负责NO生成的酶、3-硝基酪氨酸的表达以及CD68(+)和/或髓过氧化物酶（MPO）(+)细胞的存在情况。我们共检查了113份肝脏标本，包括64例PBC患者、19例原发性硬化性胆管炎（PSC）患者、6例非甲非乙型肝炎患者、6例酒精性肝病患者、4例隐源性肝硬化患者、4例胆道闭锁患者以及10名正常受试者。22%的PBC患者胆管上皮细胞（BECs）中3-硝基酪氨酸表达升高（P = 0.0316）。此外，PBC患者的BECs还表现出凋亡变化。在基底膜附近也观察到MPO阳性炎症细胞。相比之下，正常受试者的肝脏胆管几乎没有凋亡变化，门管区无MPO染色证据。此外，与III期和IV期相比，I期或II期PBC患者肝脏切片显示炎症细胞浸润显著增加（P = 0.0064），BECs中3-硝基酪氨酸表达升高（P = 0.0246）。3-硝基酪氨酸的存在与浸润的CD68和/或MPO阳性细胞密切相关。PBC患者胆管浸润细胞和3-硝基酪氨酸的存在也存在分期相关差异，早期疾病中增加更为明显。总之，NO和活性氧共同以3-硝基酪氨酸表示，与PBC中的胆管破坏相关，且在疾病早期尤为普遍。
