血小板衍生生长因子及其受体与病毒性肝炎肝纤维化的关系

目的研究血小板衍生生长因子在病毒性肝炎肝纤维化中的作用。方法以免疫组化技术检测血小板衍生生长因子（ＰＤＧＦ）－ＢＢ以及ＰＤＧＦ的β受体（ＰＤＧＦＲ－β）在病毒性肝炎肝组织中的表达。结果ＰＤＧＦ－ＢＢ及ＰＤＧＦＲ－β在肝组织中的表达与肝纤维化程度明显相关，肝硬变及慢性肝炎Ｓ３～４期患者肝组织ＰＤＧＦ－ＢＢ及ＰＤＧＦＲ－β表达强度明显高于急性肝炎及慢性肝炎Ｓ０～２期患者，同时与结蛋白、Ⅲ型前胶原肽在肝组织中的表达以及血清金属蛋白酶组织抑制因子－１（ＴＩＭＰ－１）呈明显正相关。结论ＰＤＧＦ－ＢＢ及ＰＤＧＦＲ－β不仅对星状细胞的活化、分裂、增殖及其合成胶原等细胞外基质（ＥＣＭ）均有明显的促进作用，而且可能通过上调ＴＩＭＰ－１减少ＥＣＭ的降解，促进肝纤维化的发生和进展过程。     

血小板源生长因子—B及其受体在哮喘豚鼠气道中的表达

为探讨血小板源生长因子－Ｂ多肽（ＰＤＧＦ－Ｂ）在哮喘发病中的作用，应用免疫组织化学方法，检测了豚鼠哮喘模型气道及肺组织中ＰＤＧＦ－Ｂ多肽及其受体（ＰＤＧＦＲ－β）的表达。结果表明：实验组气道壁及周围组织有大量ＰＤＧＦ－Ｂ多肽阳性细胞，主要为气道上皮细胞及浸润的炎症细胞。ＰＤＧＦＲ－β阳性细胞主要分布在气道基底膜及周围结缔组织，偶见于平滑肌和肺间质。提示ＰＤＧＦ－Ｂ多肽及ＰＤＧＦＲ－β的表达与哮喘发     

转化生长因子β3在病毒性肝炎肝组织中的表达及其意义

目的为了解转化生长因子β３（ＴＧＦ－β３）在病毒性肝炎肝组织中的表达及其与肝纤维化的关系。方法对３３例病毒性肝炎病人肝组织进行了ＴＧＦ－β３免疫组化研究。结果ＴＧＦ－β３主要分布在血窦壁及窦内细胞、坏死灶、汇管区、纤维间隔、假小叶中的肝细胞以及重型肝炎坏死区的肝细胞。其阳性表达的强度为肝硬变慢性重型肝炎＞慢性肝炎重度＞中度＞轻度＞急性肝炎；与肝功能损害的关系表明，随着ＴＧＦ－β３在肝组织中表达的增高，血清总胆红质升高明显，而凝血酶原时间活动度明显下降。结论ＴＧＦ－β３在肝组织中的表达与病毒性肝类肝纤维化及肝硬变、重型肝炎的发生发展及预后有密切关系。     

血小板源生长因子-B及其受体在哮喘豚鼠气道中的表达

为探讨血小板源生长因子－Ｂ多肽（ＰＤＧＦ－Ｂ）在哮喘发病中的作用，应用免疫组织化学方法，检测了豚鼠哮喘模型气道及肺组织中ＰＤＧＦ－Ｂ多肽及其受体（ＰＤＧＦＲ－β）的表达。结果表明：实验组气道壁及周围组织有大量ＰＤＧＦ－Ｂ多肽阳性细胞，主要为气道上皮细胞及浸润的炎症细胞。ＰＤＧＦＲ－β阳性细胞主要分布在气道基底膜及周围结缔组织，偶见于平滑肌和肺间质。提示ＰＤＧＦ－Ｂ多肽及ＰＤＧＦＲ－β的表达与哮喘发病关系密切。     

病毒性肝炎肝细胞凋亡及与肝纤维化的关系

目的 研究病毒性肝炎肝细胞凋亡及与肝纤维化的关系。方法 以原位末端标记及免疫组化检测４０例慢性病毒性肝炎（ＣＨ）肝组织细胞调亡相关线状断裂ＤＮＡ以及Ｆａｓ抗原、转化生长因子β１（ＴＧＦ－β１）、Ⅲ型前胶原肽（ＰⅢＰ）在肝组织中的表达;以酶联免疫吸附测定（ＥＬＩＳＡ）检测血清可溶性Ｆａｓ（ｓＦａｓ）及ＴＧＦ－β１。结果 ＣＨ肝细胞ＤＮＡ损伤与肝组织Ｆａｓ抗原、ＴＧＦ－β１表达及血清ｓＦａｓ、ＴＧＦ－     

血清组织金属蛋白酶抑制因子-1检测与病毒性肝炎肝纤维化关系

血清组织金属蛋白酶抑制因子－１检测与病毒性肝炎肝纤维化关系辛绍杰张玲霞王松山王林杰我们检测了病毒性肝炎患者血清组织金属蛋白酶抑制因子－１（ＴＩＭＰ－１）含量，探讨其与肝纤维化及转化生长因子β（ＴＧＦ－β１）在肝组织中表达的关系。１材料和方法２５例患者...     

血小板源生长因子对大鼠肝层星状细胞增殖和胶原及血小板源 …

目的 证实血小板源生长因子（ＰＤＧＦ）对体外培养大鼠肝星状细胞增殖和胶原基因表达及ＰＤＧＦ自分泌的作用。方法 ⑴采用完全无血清培养,用＾３Ｈ－ＴｄＲ掺入检测了ＰＤＧＦ、转化生长因子β１（ＴＧＦ－β１）和表皮生长因子（ＥＧＦ）对肝星状细胞的ＤＮＡ合成作用;⑵应用Ｎｏｒｔｈｅｒｎ分子杂交检测了ＰＤＧＦ对肝星状细胞的Ⅰ、Ⅲ型前胶原及ＰＤＧＦ－Ｂ等ｍＲＮＡ表达水平的影响。结果 ＰＤＧＦ、ＥＧＦ均可剂量依赖     

几种生长因子及血管内皮细胞生长因子受体在胃肠道平滑肌肉瘤中的表达

本研究是应用免疫组化法观察细胞因子血管内皮细胞生长因子（ＶＥＧＦ）、血小板衍生生长因子（ＰＤＧＦｂ）、转化生长因子（ＴＧＦβ）、碱性成纤维细胞生长因子（ＢＦＧＦ）及血管内皮细胞生长因子受体（ＶＥＧＦＲ）在平滑肌肉瘤组织和ＥＬＩＳＡ法在细胞株的表...     

胶质瘤细胞血小板源生长因子B链的纯合二聚体与其受体基因？…

目的 探讨胶质瘤细胞血小板源生长因子Ｂ链的纯合二聚合（ＰＤＧＦＢＢ）及其受体（ＤＧＦＲ）基因表达和ＰＤＧＦＲ活化汪洋在胶质瘤发生、发展听作用。方法 用原位杂交和免疫组化染色观察了７３例不同级别的人胶质瘤组织标本。结果 ６２例（８４．９％）的肿瘤细胞表达ＰＤＧＦＢｍＲＮＡ,基阳性率和阳性肿瘤细胞含量均随肿瘤恶性程度升高而递增。ＰＤＧＦＲα、ＰＤＧＦＲβ和这两种受体及其信号传递通路活化标记物酪氨酸磷酸     

肝纤维化相关性细胞因子研究进展

与肝纤维化相关的细胞因子有转化生长因子β（ＴＧＦ－β）、白介素１（ＩＬ－１）、肿瘤坏死因子α（ＴＮＦ－α）、干扰素γ（ＩＦＮ－γ）、血小板源性生长因子（ＰＤＧＦ）等。这些细胞因子及其网络的相互作用对肝脏细胞外基质的合成与降解起调控作用，在肝纤维化形成的不同阶段起重要作用     

Hepatic stellate cell proliferation is an early platelet-derived growth factor-mediated cellular event in rat cholestatic liver injury.

SUMMARY: After liver injury, hepatic stellate cells (HSC) undergo a pleiotropic response termed "activation" that also occurs in culture models and ultimately leads to the conversion of HSC into myofibroblasts expressing smooth muscle alpha-actin (alpha-SMA). The onset of HSC proliferation in primary culture coincides with the induction of platelet-derived growth factor receptor-beta (PDGFR-beta) expression, while platelet-derived growth factor (PDGF) is the most potent mitogen for culture-activated HSC. Yet, the mechanisms and the stage of activation required for HSC proliferation in the intact liver are still uncertain. In the present study, we analyzed the proliferative response of HSC to rat cholestatic liver injury and the role of PDGF in this response. After in vivo incorporation of bromodeoxyuridine (BrdU), pure vitamin A-containing HSC were isolated at different time points after bile duct ligation (BDL) or sham operation and were analyzed by means of flow cytometry. The induction of HSC proliferation, as ascertained by BrdU incorporation, occurred between 24 and 48 hours and reached a plateau as soon as 48 hours after BDL. Flow cytometry and immunoblot analyses of HSC indicated that the induction of proliferation in HSC coincided with the up-regulation of PDGFR-beta protein on their surface but preceded that of alpha-SMA. A dose-dependent inhibition of PDGF-BB-induced HSC proliferation by STI571, a PDGF receptor tyrosine kinase inhibitor, was documented in vitro. Daily intraperitoneal injections of STI571 (20 mg/kg) caused a 60% reduction in BrdU positive isolated HSC and in the amount of desmin-immunoreactive sinusoidal cells on liver tissue sections in 48-hour bile duct-ligated rats. These results indicate that cholestatic liver injury elicits an early proliferative response in HSC that is mainly mediated by PDGF, and which precedes HSC phenotypic conversion into myofibroblasts.     

The myofibroblastic conversion of peribiliary fibrogenic cells distinct from hepatic stellate cells is stimulated by platelet-derived growth factor during liver fibrogenesis

The origin of myofibroblasts and the factors promoting their differentiation during liver fibrogenesis remain uncertain. During biliary-type fibrogenesis, the proliferation and chemoattraction of hepatic stellate cells (HSC) toward bile ducts is mediated by platelet-derived growth factor (PDGF), while myofibroblastic conversion of peribiliary cells distinct from HSC also occurs. We herein examined the phenotype of these peribiliary myofibroblasts as compared with myofibroblastic HSC and tested whether their differentiation was affected by PDGF. Biliary-type liver fibrogenesis was induced by common bile duct ligation in rats. After 48 hours, periductular fibrosis in portal tracts colocalized with smooth muscle alpha-actin-immunoreactive myofibroblasts, the majority of which were desmin negative. Simultaneously, in sinusoids, desmin immunoreactivity was induced in a large number of HSC, which were smooth muscle alpha-actin negative. Cultures of peribiliary myofibroblasts were expanded from isolated bile duct segments and compared with myofibroblastic HSC. Peribiliary myofibroblasts outgrowing from bile duct segments expressed smooth muscle alpha-actin, alpha1 (I) collagen mRNA, and PDGF receptor-beta subunit. Desmin immunoreactivity gradually decreased in cultured peribiliary myofibroblasts, contrasting with constant labeling of all myofibroblastic HSC. In addition, IL-6 expression in peribiliary myofibroblasts was up to 100-fold lower than in myofibroblastic HSC, whereas the expression of the complement-activating protease P100 in both cell types showed little difference and that of the extracellular matrix component fibulin 2 was similar. The expression of smooth muscle alpha-actin protein in cultured peribiliary myofibroblasts was stimulated by PDGF-BB and inhibited by STI571, a PDGF receptor tyrosine kinase inhibitor, whereas in bile duct-ligated rats, the administration of STI571 caused a significant decrease in peribiliary smooth muscle alpha-actin immunoreactivity, and to a lesser extent, a decrease in peribiliary fibrosis. These results indicate that peribiliary cells distinct from HSC undergo a PDGF-mediated conversion into myofibroblasts expressing IL-6 at lower levels than myofibroblastic HSC and contribute to the initial formation of biliary-type liver fibrosis.     

抗组胺治疗对实验性肝炎大鼠肥大细胞浸润及c-Kit和SCF表达的影响

 目的：研究c-Kit和干细胞因子（SCF）在实验性肝炎大鼠肝脏组织的表达及抗组胺治疗后的变化。方法：取Wistar大鼠30只,随机分为3组：正常对照组（NC）、慢性肝炎组（CH）和抗组胺治疗组（AH）。CH组采用复合因素造模（用40%四氯化碳油溶液皮下注射,同时辅以低蛋白、低胆碱、高脂肪、高醇饮食）,AH组在CH的基础上给予抗组胺治疗（酮替芬）。4周末处死动物,取血分别检测血浆类胰蛋白酶（TS）和组胺（HA）水平,同时观察肝脏组织学变化及肥大细胞形态改变。应用免疫组织化学方法观察肝脏c-Kit和SCF的表达。用RT-PCR方法观察肝组织c-Kit和SCF mRNA的表达水平。结果：（1）与正常对照组比较,慢性肝炎组TS、血和肝组织HA水平均有明显升高（P<0.05）,经抗组胺治疗后,TS、血和肝组织HA水平均明显降低（P<0.05）。（2）光镜下,慢性肝炎组有脂肪变性和纤维化形成,而治疗组肝损伤明显减轻;甲苯胺蓝染色可见慢性肝炎组肝脏血管周围及纤维间隔内大量正在脱颗粒和已经脱颗粒的充满紫色颗粒的肥大细胞。治疗组仅见胞浆中充有少量紫色颗粒。定量统计发现,慢性肝炎组肥大细胞数目较正常对照组明显升高（P<0.05）,抗组胺治疗后,肥大细胞数目明显减少（P<0.05）。（3）RT-PCR结果显示抗组胺治疗可以下调c-Kit和SCF mRNA表达水平（P<0.05）。免疫组织化学染色显示慢性肝炎组高表达c-Kit和SCF（均P<0.05）,抗组胺治疗可以下调二者的表达（P<0.05）,而且二者的表达均与HA水平呈明显正相关。结论：肥大细胞参与了实验性肝炎的炎症过程。酮替芬可以通过下调肥大细胞膜受体c-Kit及其配体SCF的表达使肥大细胞脱颗粒减少,组胺释放减少,从而减轻肝脏炎症。     

Bcl-2 和Bax蛋白在慢性病毒性肝炎肝组织中的表达

目的研究细胞凋亡相关的Ｂｃｌ－２和Ｂａｘ蛋白在慢性病毒性肝炎（ＣＨ）肝组织中表达的情况与该病发生发展的关系。方法对３５例不同病变程度的ＣＨ肝组织用免疫组化法检测Ｂｃｌ－２和Ｂａｘ的表达及定位。结果Ｂｃ１－２和Ｂａｘ分布基本一致，轻、中度ＣＨ主要见于碎屑样坏死（ＰＮ）区中的单个核细胞（ＭＮ），邻近ＰＮ区边缘的肝细胞浆中也有强阳性表达。ＨＥ染色观察，这些Ｂｃｌ－２和Ｂａｘ阳性肝细胞多呈重度水样变性或嗜酸性变。在重度ＣＨ肝组织中Ｂｃｌ－２和Ｂａｘ阳性的ＭＮ主要分布于重度ＰＮ区和桥接坏死区，周围部分肝细胞Ｂａｘ阳性，而Ｂｃｌ－２为阴性。在慢性重型肝炎，Ｂｃｌ－２和Ｂａｘ除在亚大块肝细胞坏死区浸润的ＭＮ胞浆内表达外，残存肝细胞亦呈阳性表达。结论Ｂｃｌ－２和Ｂａｘ在肝组织中的表达可能不仅与ＣＨ的细胞凋亡有密切关系，而且与慢性重型肝炎的发生发展有关     

A gain-of-function mutation in the PDGFR-beta alters the kinetics of injury response in liver and skin

Platelet-derived growth factor (PDGF) isoforms stimulate cell proliferation, migration and survival. We recently generated mice carrying a gain-of-function mutation within the activation loop of PDGF beta-receptor (PDGFR-beta D849N). Embryonic fibroblasts derived from these mice show elevated basal phosphorylation and altered kinetics for ligand-induced activation of PDGFR-beta, as well as enhanced proliferation and migration. To investigate the effect of this mutation in vivo, we used carbon tetrachloride-induced liver injury as a model system. We observed a higher basal activation of mutant PDGFR-beta in unchallenged livers; however, the difference in activation upon carbon tetrachloride stimulation was lower than expected, an effect that might be explained by a delayed response of the mutated receptor toward reactive oxygen species. Mutant mice showed enhanced proliferation of nonparenchymal liver cells and activation of hepatic stellate cells, leading to a small increase in early fibrosis formation. Another mouse strain lacking the binding site for phosphatidylinositol-3' kinase in PDGFR-beta showed the reverse phenotype. These results suggest an important role for PDGFR-beta signaling in the early injury-response. We confirmed this hypothesis with a second injury model, cutaneous wound healing, where we observed earlier proliferation and formation of granulation tissue in D849N-mutant mice.     

Functional platelet-derived growth factor-beta (PDGF-beta) receptor expressed on early B-lineage precursor cells.

Growth and maturation of B lymphocytes from stem cells require a series of complex processes that are dependent at least in part on growth factors. Uncontrolled expression of receptors from these early growth factors may contribute to a leukaemogenesis of such early B cell progenitors. We show here that early pre-pre-B cells, but not mature B cells, express the PDGF receptor-beta (PDGFR-beta). These receptors contain a protein tyrosine kinase domain which is activated upon ligation with PDGF in pre-pre-B cells. Further, pre-pre-B leukaemia cells seem to express more PDGFR-beta compared with their normal counterparts, suggesting a role for these receptors in growth promotion of leukaemia cells.     

Crosstalk between PDGF and IGF-I receptors in rat liver myofibroblasts: implication for liver fibrogenesis

Insulin-like growth factor I (IGF-I) and platelet-derived growth factor (PDGF) have been identified as significant mitogens for liver myofibroblasts (LMFs), one of the cell populations playing a role in liver fibrogenesis. In the present work, we aimed to elucidate a possible interaction between PDGF receptor (PDGFR) and IGF-I receptor (IGF-IR) signaling in LMFs. Among different rat liver cells, PDGFR alpha- and beta-subunits were mainly expressed in hepatic stellate cells and LMFs, and were upregulated during their in vitro cultivation. In LMFs, PDGF-BB (10 ng/ml) stimulated DNA synthesis approximately two-fold and this effect was similar to that of IGF-I. IGF-I and PDGF-BB differentially affected IGF-IR and PDGFR signaling. High concentrations of IGF-I decreased levels of IGF-IR and IRS-1 and inhibited the expression and activation of PDGFRalpha. PDGF-BB prevented IGF-I-induced downregulation of the IGF-IR, but did not affect expression of its cognate receptor subunits. Transphosphorylation of PDGFR and IGF-IR was not observed. PDGF effectively activated terminal MAP kinases, PI3 kinase and Akt kinase, whereas IGF-I demonstrated weaker effects. PLCgamma(1) was phosphorylated only in response to PDGF, but not to IGF-I. In rat LMFs, blockade of the IGF-IR via inhibition of the IGF-IR kinase completely abrogated IGF- and PDGF-induced mitogenesis and the ability of PDGF to phosphorylate PLCgamma(1). In conclusion, the presented data demonstrate that the PDGFR signaling requires a functional IGF-IR and that PDGF-BB stabilizes the IGF-IR function through preventing the IGF-I-induced downregulation of the IGF-IR. These interactions might be relevant in vivo for the fibroproliferative response during liver injury.     

Expression of CD163 in the liver of patients with viral hepatitis

CD163 is a marker of activated macrophages, and increased levels of soluble CD163 have been detected in sera obtained from patients with hepatitis. The aim of this study was to detect the expression of CD163 in the liver from patients with viral hepatitis. Frozen sections of liver specimens were obtained from 5 patients with acute viral hepatitis (AH) and from 23 patients with chronic viral hepatitis (CH). The expression of CD163 in the liver was determined immunohistochemically using monoclonal antibody to human CD163. Double immunostaining was done to assess those cell types that express CD163 in the liver. The frequencies of CD163-positive cells were significantly higher both in the portal areas and in the hepatic lobules in the liver of patients with AH compared to those with CH (p < 0.05). Double immunostaining revealed that most of the CD163-positive cells were macrophages and Kupffer cells, because they expressed CD68. The expression of CD163 was very low in endothelial cells and liver stellate cells. This study shows that macrophages are activated in hepatitis liver.     

Expression and localization of PDGF-B, PDGF-D, and PDGF receptor in the kidney of angiotensin II-infused rat

Lipid accumulation in the kidney is a marker of tissue damage and may play a role in the development of renal injury. We have previously shown that long-term administration of angiotensin II in rats causes increased expression of transforming growth factor-beta1, coupled with an accumulation of lipids in the tubular and vascular wall cells in the kidney. In this study, we examine the regulation of expression of platelet-derived growth factor (PDGF) and its receptor system and their co-localization with lipid deposits in the kidneys of angiotensin II-infused rats. Real-time RT-PCR showed that expression of PDGF-B, PDGF-D, and PDGF receptor-beta (PDGFR-beta) mRNA was increased by angiotensin II infusion, and in situ hybridization showed the co-localization of these mRNAs. Tubular cells that had increased PDGF-B mRNA expression were positive for lipid deposition and also for cellular proliferation, which was indicated by the presence of proliferating cell nuclear antigen. By contrast, in the kidneys of angiotensin II-infused rats, apoptosis occurred in tubular cells that contained deposits of iron but not lipids. The deposition of lipids and upregulation of PDGF-B, PDGF-D, and PDGFR-beta induced by administration of angiotensin II were all suppressed by the selective angiotensin II type 1 (AT(1)) receptor antagonist losartan, but not by the nonspecific vasodilator hydralazine. The findings that lipid accumulation, upregulation of PDGF-B, PDGF-D, and PDGFR-beta, and cellular proliferation were topologically associated and regulated in an AT(1) receptor-dependent manner in the kidney of angiotensin II-infused rats suggests that these phenomena are related.