Human Immunology Section, Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA.
Gastroenterology. 2011 Oct;141(4):1220-30, 1230.e1-3. doi: 10.1053/j.gastro.2011.06.063. Epub 2011 Jul 2.
BACKGROUND & AIMS: Chronic infection with hepatitis B or C virus (HBV or HCV) is a leading cause of cirrhosis by unknown mechanisms of pathogenesis. Translocation of gut microbial products into the systemic circulation might increase because of increased intestinal permeability, bacterial overgrowth, or impaired clearance of microbial products by Kupffer cells. We investigated whether the extent and progression of liver disease in patients with chronic HBV or HCV infection are associated with microbial translocation and subsequent activation of monocytes.
In a retrospective study, we analyzed data from 16 patients with minimal fibrosis, 68 with cirrhosis, and 67 uninfected volunteers. We analyzed plasma levels of soluble CD14 (sCD14), intestinal fatty acid binding protein, and interleukin-6 by enzyme-linked immunosorbent assay, and lipopolysaccharide (LPS) by the limulus amebocyte lysate assay, at presentation and after antiviral treatment.
Compared with uninfected individuals, HCV- and HBV-infected individuals had higher plasma levels of LPS, intestinal fatty acid binding protein (indicating enterocyte death), sCD14 (produced upon LPS activation of monocytes), and interleukin-6. Portal hypertension, indicated by low platelet counts, was associated with enterocyte death (P=.045 at presentation, P<.0001 after therapy). Levels of sCD14 correlated with markers of hepatic inflammation (P=.02 for aspartate aminotransferase, P=.002 for ferritin) and fibrosis (P<.0001 for γ-glutamyl transpeptidase, P=.01 for alkaline phosphatase, P<.0001 for α-fetoprotein). Compared to subjects with minimal fibrosis, subjects with severe fibrosis at presentation had higher plasma levels of sCD14 (P=.01) and more hepatic CD14+ cells (P=.0002); each increased risk for disease progression (P=.0009 and P=.005, respectively).
LPS-induced local and systemic inflammation is associated with cirrhosis and predicts progression to end-stage liver disease in patients with HBV or HCV infection.
慢性乙型肝炎或丙型肝炎病毒(HBV 或 HCV)感染是肝硬化的主要病因,但具体发病机制尚不清楚。由于肠道通透性增加、细菌过度生长或库普弗细胞清除微生物产物的能力受损,肠道微生物产物可能会向全身循环转移。我们研究了慢性 HBV 或 HCV 感染患者的肝病严重程度和进展是否与微生物易位及随后单核细胞的激活有关。
在一项回顾性研究中,我们分析了 16 例纤维化程度最小的患者、68 例肝硬化患者和 67 例未感染的志愿者的数据。我们通过酶联免疫吸附试验分析了血浆可溶性 CD14(sCD14)、肠脂肪酸结合蛋白和白细胞介素-6 的水平,并通过鲎试验分析了内毒素(LPS)的水平。这些检测均在初诊时和抗病毒治疗后进行。
与未感染者相比,HCV 和 HBV 感染者的 LPS、肠脂肪酸结合蛋白(提示肠上皮细胞死亡)、sCD14(单核细胞 LPS 激活后产生)和白细胞介素-6 的血浆水平较高。门静脉高压(血小板计数降低)与肠上皮细胞死亡有关(初诊时 P=.045,治疗后 P<.0001)。sCD14 水平与肝炎症标志物(天冬氨酸氨基转移酶 P=.02,铁蛋白 P=.002)和纤维化标志物(γ-谷氨酰转肽酶 P<.0001,碱性磷酸酶 P=.01,甲胎蛋白 P<.0001)相关。与初诊时纤维化程度较轻的患者相比,纤维化程度较重的患者 sCD14 水平较高(P=.01),肝内 CD14+细胞较多(P=.0002);且均与疾病进展风险增加相关(P=.0009 和 P=.005)。
LPS 诱导的局部和全身炎症与肝硬化有关,并可预测 HBV 或 HCV 感染患者向终末期肝病的进展。