检测子宫内膜异位症患者血清中差异表达蛋白的研究

目的：检测子宫内膜异位症（内异症）患者血清中差异表达的蛋白。方法：采用表面增强激光解吸／离子化飞行时间质谱（SELDI—TOF—MS）技术，选用WCX2蛋白质芯片对50例内异症及48例对照组血清标本进行检测以筛选内异症血清中差异表达的蛋白。结果：在Mr 0～50000范围内，检测出106个蛋白峰。内异症患者血清中差异表达的蛋白峰有4个。将发现的差异蛋白峰在Swiss蛋白数据库中搜索，发现Mr 9280蛋白峰与玻璃粘连蛋白Vitronectin相符。Vitronectin属于整合素家族，在内异症的粘附、侵袭、血管形成过程中起重要作用。其他的蛋白峰没有发现与之相匹配的蛋白，提示可能为新的蛋白质。结论：内异症患者血清中存在差异表达的蛋白，其对内异症的早期诊断具有一定的临床意义。SELDI蛋白芯片技术是一种快速、简单易行、样本用量少、高通量、重复性好的分析方法，具有广阔的临床应用前景。     

Expression of the complement membrane attack complex and its inhibitors in Pick disease brain

The immunohistochemical localization of the complement membrane attack complex (MAC) was examined in Pick disease brain and compared with the distribution of three of its inhibitors, vitronectin, protectin and clusterin. Pick bodies were stained intensely for both the MAC and protectin, weakly for vitronectin, but negatively for clusterin. However, the clusterin antibody intensely stained some pyramidal neurons in affected cortical areas, including ballooned neurons. The present study indicates that a complement-mediated attack is associated with the formation of Pick bodies, and provides further suggestive evidence that clusterin may be a marker for active neuronal degeneration.     

Localization of vitronectin- and fibronectin-receptors on cultured human glioma cells

Utilizing a human astrocyte-derived glioma cell line, we have demonstrated the presence of a vitronectin receptor, αvβ3, and a fibronectin receptor, α5β1, on the surface of the cells spreading on the respective adhesion molecules by immunohistochemical analyses. By phase-contrast microscopy, these receptors were found to be expressed predominantly in the focal contact-like area, suggesting that they were involved in the spreading of the cells upon contact with these adhesion molecules. Interestingly, they appeared to have differential functions and roles as integrins as evidenced by different time-dependent distribution profiles on the cell surface in the serum-containing medium. Furthermore, both vitronectin and fibronectin seem to have chemotactic effects onto the glioma cells as observed in a Boyden chamber study. Although these receptors are not expected to be present on the surface of astrocytes under physiological conditions, they may be expressed thereon and involved in gliosis when the cerebral vasculature is traumatized and, thereby, blood proteins, including vitronectin and fibronectin, come into contact with the astrocytes.     

整合素配体玻连蛋白在人精子的表达及其与受精的关系

目的 :进一步研究整合素配体玻连蛋白 (Vn)在人精子的表达及其与受精的关系。方法 :选用 1 4例生育力正常的成年男性及 8例精液常规分析正常的不明原因不育男性患者的精液标本 ,液化后提取上游精子。精子体外获能后用兔抗人 Vn多克隆抗体及羊抗兔 Ig G-FITC行免疫染色。然后用流式细胞仪计数 Vn表达阳性精子百分数。部分获能精子同时与去透明带金黄地鼠卵行异种体外受精 (SPA)以检测其受精力 ,比较两组获能精子表面Vn表达阳性精子百分率及受精率差异并分析受精率与 Vn表达阳性的获能精子百分数之间的相关性。结果 :生育组与不育组获能精子 Vn表达水平分别为 2 1 .2 4± 1 1 .70 %与3.6 4± 3.2 7% ,不育组明显低于生育组 (P<0 .0 5)。生育组受精率大于 1 0 % ,不育组受精率小于 1 0 % ,符合划分生育力正常与异常的标准。所有标本 Vn表达阳性的获能精子百分率与精子受精率间具有相关性 (r=0 .476 )。结论 :人获能精子表面存在一定水平的整合素配体玻连蛋白表达 ;Vn参与受精过程 ;Vn表达异常可能与一些不明原因的不育有关     

Regulation of vitronectin receptor expression by retinoic acid on human melanoma cells

Summary The integrin family of adhesion receptors is likely to be important for tumor cell invasion and dissemination. We have studied the effects of the differentiating agents retinic acid on integrin expression by the human melanoma cell line MeWo. Our results show that this agent inhibits cellular proliferation, increases melanin content and induces morphological changes in MeWo cells. Functionally, these alterations are associated with an enhanced adhesion to matrix protein vitronectin and higher levels of expression of vitronectin receptor on the cell surface. This is accompanied by increased levels of α_v integrin mRNA. Although the mechanism by which retinoic acid regulates the expression of vitronectin receptor in MeWo cells needs further examination, this system may represent a good model for understanding the role of this receptor in melanoma progression, as well the molecular basis for retinoic acid therapy in these tumors.     

Validation of the vitronectin knockout mouse as a model for studying myocardial infarction: Vitronectin appears to influence left ventricular remodelling following myocardial infarction

BACKGROUND:

Vitronectin (VN) is an abundant acute-phase plasma protein that regulates cell adhesion and migration as well as interactions with components of the plasminogen activator/plasmin system, specifically plasminogen activator inhibitor type 1. This system plays a major role in tissue remodelling regulating wound healing after myocardial infarction.

OBJECTIVES:

To investigate the feasibility of using VN knockout mice (VN^−/−) to study the role of VN on ventricular remodelling following myocardial infarction.

METHODS:

Specifically bred VN^−/− mice and normal wild-type (VN^+/+) mice underwent coronary artery ligation and were assessed 28 days postligation using echocardiography and morphometric histology.

RESULTS:

No difference was observed between VN^−/− mice and VN^+/+ mice with respect to gross phenotype, weight, coronary anatomy or echocardiographically measured ejection fraction (56%). Following myocardial infarction, VN^−/− mice exhibited less ventricular dilation and less impairment in echocardiographic ejection fraction compared with VN^+/+ mice (48% versus 41%; P=0.01). VN^−/− mice also exhibited smaller infarcts on morphometric analysis.

CONCLUSIONS:

The results of the present study confirmed the feasibility of using coronary artery ligation in VN knockout mice to investigate the role of VN in post-myocardial infarction remodelling. The absence of VN appears to result in favourable effects on wound healing. These data suggest that this model may offer novel insights into the role of VN in the regulation of myocardial remodelling.     

Immunohistochemical localization of C3d fragment of complement and S-protein (vitronectin) in normal and diseased human kidneys: association with the C5b-9 complex and vitronectin receptor

The localization of C3d, a fragment produced by C3 activation and S-protein (vitronectin), a regulatory factor of C5b-9, was studied immunohistochemically in normal human kidney and renal biopsies from patients with several types of glomerulonephritis. Immunofluorescent staining of the normal kidneys showed that C3d was present along the glomerular basement membrane (GBM), tubular basement membrane (TBM) and arterioles, and that S-protein was present in the GBM, mesangium, TBM, and arterioles. Immunoelectron microscopy of isolated basement membranes showed that C3d was localized exclusively on the epithelial side of the GBM, and that S-protein was present along both the epithelial and endothelial sides. In nephritic tissues, glomerular staining of C3d, C5b-9, and S-protein was increased when compared with that in normal tissues. S-protein, frequently co-localized with C3d and C5b-9 neoantigen, was intensely positive in the immune deposits of glomerular capillaries and the mesangial area, overlapping the background staining of GBM and mesangial matrix. S-protein and its receptor were occasionally co-localized in the glomeruli. These findings indicate that C3d and S-protein are normally present in the glomeruli. Co-staining of C3d, C5b-9 neoantigen, and S-protein within the immune deposits of nephritic kidneys suggests in situ binding of S-protein to locallyformed C5b-9 complex, or merely co-distribution of S-protein with the complex, rather than trapping of large molecular SC5b-9 complex from the circulation.     

破骨细胞的骨吸收机制

破骨细胞是一种巨大的多核细胞,起源于单核巨噬细胞/单核系造血前体细胞,在骨吸收过程中发挥重要作用。破骨细胞的形成和活性异常可导致骨质疏松、类风湿关节炎、关节置换后假体无菌性松动等许多疾病,因此破骨细胞是治疗这些疾病的靶点之一。目前对破骨细胞的分化形成研究较多,但对破骨细胞如何识别、降解骨组织方面的研究较少。骨盐被认为是破骨细胞识别的重要成分,但是近年来的研究发现骨基质不是破骨细胞激活的必需成分,玻连蛋白包被的培养皿也能使破骨细胞出现骨吸收的特有形态,玻连蛋白对破骨细胞的激活有重要的作用。此外,最近的研究证明骨基质降解产物的吞入和分泌对破骨细胞的分化和功能的保持有重要意义。这些分子机制的研究可能为骨骼疾病提供新的治疗靶点。     

Chimeric vitronectin:insulin-like growth factor proteins enhance cell growth and migration through co-activation of receptors

Complexes comprised of IGF-I, IGF-binding proteins and the ECM protein vitronectin (VN) stimulate cell migration and growth and can replace the requirement for serum for the ex vivo expansion of cells, as well as promote wound healing in vivo. Moreover, the activity of the complexes is dependent on co-activation of the IGF-I receptor and VN-binding integrins. In view of this we sought to develop chimeric proteins able to recapitulate the action of the multiprotein complex within a single molecular species. We report here the production of two recombinant chimeric proteins, incorporating domains of VN linked to IGF-I, which mimic the functions of the complex. Further, the activity of the chimeric proteins is dependent on co-activation of the IGF-I- and VN-binding cell surface receptors. Clearly the use of chimeras that mimic the activity of growth factor:ECM complexes, such as these, offer manufacturing advantages that ultimately will facilitate translation to cost-effective therapies.