Ultrastructural localization of factor VIII procoagulant antigen in human liver hepatocytes

Factor VIII is generally believed to circulate in blood as a multimeric complex of two glycoproteins which are physiologically and immunologically distinct. One component of the factor VIII complex is factor VIII procoagulant activity (FVIII:C) which is associated with factor VIII/procoagulant antigen (FVIII:Ag, formerly FVIII/CAg). The second, larger unit of the complex is factor VIII/von Willebrand factor (vWF:Ag, formerly factor VIII-related antigen or FVIIIRAg). FVIII:C has anti-haemophilic activity and is defective or deficient in patients with classical haemophilia, and vWF:Ag is absent in patients with von Willebrand disease. FVIII:Ag was demonstrated recently in endothelial cells lining hepatic sinusoids, by using immunoperoxidase staining and light microscopy, whereas biochemical data had indicated its presence predominantly in the hepatocyte fractions and in lesser amounts in endothelial cells. Moreover, recent hybridization experiments detected FVIII:C messenger RNA in liver and kidney tissues. Despite several efforts, the cells responsible for FVIII:C synthesis have not been unequivocally identified. Here we use protein A-gold complex labelling to demonstrate the ultrastructural localization of FVIII:C in human liver cells; the results indicate that hepatocytes may synthesize FVIII:Ag.     

血清PSA指标与经直肠超声造影对前列腺癌的诊断

目的:探讨血清前列腺特异性抗原(PSA)指标,游离前列腺特异性抗原(f-PSA)、总前列腺特异性抗原(T-PSA),前列腺特异性抗原密度(PSAD)与经直肠前列腺超声造影对前列腺癌(Prostate Cancer,PCa)的诊断价值.方法:获取59例血清PSA升高的患者的f PSA及T-PSA、前列腺体积的三个径(L、W、H),所有病例均经直肠超声造影检查,并在超声引导下进行前列腺穿刺.结果:前列腺癌组患者的发病年龄要比良性前列腺增生(Benign prostate hyperplasia,BPH)组大,PSAD比BPH组高.前列腺癌组的f/T-PSA比良性前列腺增生组低.前列腺癌组患者的显影时间、达峰时间、加速时间较良性前列腺增生组患者短,绝对增强强度较良性前列腺增生组高.前列腺癌组患者的强度减半时间比良性前列腺增生组患者短.结论:前列腺癌组的前列腺造影结果表现为"快进快出".血清f/T-PSA、PSAD及经直肠超声造影技术对前列腺良恶性病变的鉴别诊断具有一定的临床价值.     

Distribution of factor VIII mRNA and antigen in human liver and other tissues

The cellular site of synthesis of factor VIII (FVIII:C; anti-haemophilic factor) has long been sought. Previous studies suggested the liver as a major site of synthesis, but extrahepatic sources such as spleen and lung have been implicated. Using an immunoradiometric assay (IRMA), we recently localized factor VIII antigen (FVIII:Ag, formerly FVIII:CAg), to whole perfused guinea pig liver and spleen, and to isolated hepatocytes, with lesser or trace amounts in other tissues. Using an immunohistological technique, Stel et al. detected FVIII:Ag in normal human liver sinusoidal endothelial cells, while Exner et al. detected FVIII:Ag by IRMA in extracts of human lymph nodes, lung, liver and spleen. The localization of antigen in tissues does not, however, distinguish sites of factor VIII synthesis from those of storage, and such experiments are subject to misinterpretation due to entrapment of plasma factor VIII in tissues. The recent cloning of the human factor VIII gene provides hybridization probes for the detection of factor VIII messenger RNA in cells, thus directly determining sites of synthesis. During complementary DNA cloning, we detected factor VIII mRNA in liver, and it has been localized by others in liver and placenta and in liver and kidney. In the present study, we detected factor VIII mRNA in isolated human hepatocytes, in spleen and in numerous tissues including lymph nodes and kidney, but not in white blood cells or cultured endothelial cells. We also found that the factor VIII, factor VII, factor IX and protein C antigens in liver are predominantly localized in hepatocytes, while very little von Willebrand factor antigen (vWF:Ag, formerly FVIIIR Ag) is detectable in this organ.     

抗小鼠雄性特异性抗原（H—Y抗原）单克隆抗体的研究

将经Ｃ５７ＢＬ／６Ｊ雄鼠脾细胞免疫的同系雌鼠脾细胞与Ｂａｌｂ／ｃ小鼠骨髓瘤ＳＰ２／０细胞进行融合,以雌、雄鼠脾细胞作细胞性ＥＬＩＳＡ、间接免疫荧光和精细胞间接免疫荧光技术进行筛选,共建立了５株稳定分泌抗Ｈ－Ｙ抗原的单克隆抗体杂交瘤细胞株。该杂交瘤细胞可在Ｃ５７ＢＬ／６Ｊ与Ｂａｌｂ／ｃ杂交子一代雌性小鼠腹腔生长并形成腹水性抗体。鉴定结果证明这些抗体具有较好的特异性。     

胎肝Sca-1+细胞治疗STZ诱导小鼠糖尿病的实验研究

目的探讨小鼠胎肝组织中的干细胞抗原1阳性的细胞(Sca-1+细胞)治疗链脲佐菌素(STZ)诱导糖尿病鼠的潜能.方法取14.5 d的C57BL/6J小鼠胎肝,制作细胞悬液,用单克隆免疫磁珠细胞分离技术分离Sca-1+细胞,将2×105个雄性小鼠Sca-1+细胞输注到STZ诱导的C57BL/6J雌性小鼠体内,以后每7 d定时测定小鼠血糖,第38 d处死受体小鼠取胰腺组织固定、切片,免疫组化观察胰腺组织中胰岛素阳性的β细胞变化.结果小鼠胎肝Sca 1+细胞能够有效抑制STZ诱导小鼠血糖的持续升高,明显降低糖尿病鼠的死亡率.受体小鼠胰岛细胞结构清楚,其中可见表达胰岛素的β细胞,荧光原位杂交显示小鼠胰岛内有Y染色体阳性杂交点.结论小鼠胎肝Sca-1+细胞具有一定的治疗小鼠糖尿病的作用.