Biomedical subjects

Luisa Campagnolo

Publications and source records attributed to Luisa Campagnolo.

6 recordsLinked to original sources

PubMed2006

A plasmid-encoded VEGF siRNA reduces glioblastoma angiogenesis and its combination with interleukin-4 blocks tumor growth in a xenograft mouse model.

Angiogenesis is required for the development and biologic progression of glioblastoma multiform (GBM), which is the most malignant infiltrative astrocytoma. Vascular endothelial growth factor (VEGF) plays a predominant role in the increased vascularity and endothelial cell proliferation in GBMs driven by the expression of pro-angiogenic cytokines. In this study, we employed a vector-encoded VEGF siRNA to impair VEGF secretion from U87 human glioblastoma cells. The direct intra-tumor injection of a siRNA-encoding plasmid complexed with linear polyethylenimine (PEI) efficiently reduced the vascularization of treated tumors in xenografts established in SCID mice by subcutaneous inoculation of U87 cells, but was not able to reduce tumor growth. We then sought to strengthen the in vivo action of our siRNA by coupling it to a well known direct antiangiogenic agent, mouse interleukin 4 (mIL4). We infected U87 cells with a retroviral vector coexpressing the VEGF siRNA and mIL4 and produced stable cell lines that we used for an in vivo experiment of subcutaneous injection in SCID mice. In this setting, the concomitant expression of mIL4 and siRNA totally abolished the growth of subcutaneous tumors. These results suggest that our retroviral vector might be employed as a potential tool in future antiangiogenic gene therapy trials for glioblastoma.

Animals↗

PubMed2005

Dosage-dependent requirement for mouse Vezf1 in vascular system development.

Vezf1 is an early development gene that encodes a zinc finger transcription factor. In the developing embryo, Vezf1 is expressed in the yolk sac mesoderm and the endothelium of the developing vasculature and, in addition, in mesodermal and neuronal tissues. Targeted inactivation of Vezf1 in mice reveals that it acts in a closely regulated, dose-dependent fashion on the development of the blood vascular and lymphatic system. Homozygous mutant embryos display vascular remodeling defects and loss of vascular integrity leading to localized hemorrhaging. Ultrastructural analysis shows defective endothelial cell adhesion and tight junction formation in the mutant vessels. Moreover, in heterozygous embryos, haploinsufficiency is observed that is characterized by lymphatic hypervascularization associated with hemorrhaging and edema in the jugular region; a phenotype reminiscent of the human congenital lymphatic malformation syndrome cystic hygroma.

Animals↗

PubMed2005

EGFL7 is a chemoattractant for endothelial cells and is up-regulated in angiogenesis and arterial injury.

The endothelium of the adult vasculature is normally quiescent, with the exception of the vasculature of the female reproductive system. However, in response to appropriate stimuli (ie, wound healing, atherosclerosis, tumor growth and metastasis, arthritis) the vasculature becomes activated and grows new capillaries through angiogenesis. We have recently identified a novel endothelial-restricted gene, Egfl7, that encodes a 41-kd secreted protein (Fitch MJ, Campagnolo L, Kuhnert F, Stuhlmann H: Egfl7, a novel epidermal growth factor-domain gene expressed in endothelial cells. Dev Dyn 2004, 230:316-324). Egfl7 is expressed at high levels early during mouse embryonic development and is strictly associated with the vascular bed. In this study, we investigated Egfl7 expression in the quiescent adult vasculature, in the pregnant uterus, and in two different models of arterial injury, namely ballooning and ferric chloride injury. By RNA in situ hybridization, Egfl7 expression in the vasculature was found to be restricted to the endothelium of the capillaries and mature vessels. In the pregnant uterus, increased vascularization was accompanied by up-regulation of Egfl7. On arterial injury, Egfl7 expression was up-regulated in the regenerating endothelium, but not in the neointima. Importantly, the EGFL7 protein acted as a chemoattractant for embryonic endothelial cells and fibroblasts in a cell migration assay. Together, these results suggest that Egfl7 functions in the formation and maintenance of endothelial integrity and that its up-regulation may be a critical component in the reorganization of the vascular bed in response to angiogenic stimuli.

Adult↗

PubMed2004

Expression and role of PDGF-BB and PDGFR-beta during testis morphogenesis in the mouse embryo.

The role played by PDGF in testis morphogenesis is still incompletely understood. The present study investigates the expression and potential role of platelet-derived growth factor-BB (PDGF-BB) and its receptor, PDGF receptor beta (PDGFR-beta), during mouse testis cord formation, and the possibility that the growth factor may be involved in the migration to the gonad of mesenchymal cells of mesonephric origin. Studies from this laboratory have previously shown that mesenchymal cells that migrate from the mesonephros into the gonad, to form peritubular myoid cells and most of the intertubular cells, can be identified by the presence on their surface of the p75 neurotrophin receptor (p75NTR), and can be isolated to near-purity by immunomagnetic selection with anti-p75NTR antibody. We show here that mesonephric p75NTR(+) cells also bear the PDGFR-beta, and are able to migrate and proliferate in vitro in response to PDGF-BB. PDGF-BB is expressed at higher levels in male than female developing gonads, suggesting a role for this factor in testis development. Such a role is further supported by the observation that addition of PDGF-BB to serum-free medium is sufficient to allow organ-cultured male 11.5 days post-coitum urogenital ridges to form testis cords. Finally, we show that mesonephric cell motility and growth induced by exposure to PDGF-BB involve mitogen-activated protein kinases (MAPK) and phosphatidylinositol-3 kinase (PI3-K) pathways, as MAPK inhibitor U0126 and PI3K inhibitor Ly294002 inhibit migration and proliferation in vitro assays. The present findings support the hypothesis that the PDGF/PDGFR system plays a key role in testis morphogenesis in the mouse embryo.

Animals↗

PubMed2004

Egfl7, a novel epidermal growth factor-domain gene expressed in endothelial cells.

We report the cloning and characterization of a novel epidermal growth factor (EGF) domain gene that was identified in a retroviral gene entrapment screen and is expressed in endothelial cells. This gene encodes a protein of 278 amino acids with an amino-terminal signal peptide and two centrally located EGF-like domains. We have named this novel gene in accordance with the guidelines of the Mouse Genome Informatics group Egfl7, for EGF-like domain 7. Egfl7 mRNA is expressed in highly vascularized adult tissues such as the lung, heart, uterus, and ovary. In addition, Egfl7 is expressed early during mouse embryogenesis and in undifferentiated murine embryonic stem cells. The analysis of Egfl7 expression in embryonic day 9.5 embryos by in situ hybridization indicates that Egfl7 is expressed in vascular structures in both the embryo proper and the yolk sac and at sites of mesodermal precursors of angioblasts. Within the cell, EGFL7 protein is localized to the endoplasmic reticulum and Golgi apparatus, suggesting that the protein is targeted for secretion. Indeed, recombinant EGFL7 is readily detectable in the supernatant media of transiently transfected HEK293 cells. We also report the identification of an Egfl7 paralog, Egfl8, and show that EGFL8 protein shares similar domains and molecular weight with EGFL7.

Aging↗

PubMed2003

Mouse matriptase-2: identification, characterization and comparative mRNA expression analysis with mouse hepsin in adult and embryonic tissues.

We report the identification and characterization of mouse matriptase-2 (m-matriptase-2), an 811-amino-acid protein composed of an N-terminal cytoplasmic domain, a membrane-spanning domain, two CUB (complement protein subcomponents C1r/C1s, urchin embryonic growth factor and bone morphogenetic protein 1) domains, three LDLR (low-density-lipoprotein receptor class A) domains and a C-terminal serine-protease domain. All m-matriptase-2 protein domain boundaries corresponded with intron/exon junctions of the encoding gene, which spans approx. 29 kb and comprises 18 exons. Matriptase-2 is highly conserved in human, mouse and rat, with the rat matriptase-2 gene ( r-maltriptase-2 ) predicted to encode transmembrane and soluble isoforms. Western-blot analysis indicated that m-matriptase-2 migrates close to its theoretical molecular mass of 91 kDa, and immunofluorescence analysis was consistent with the proposed surface membrane localization of this protein. Reverse-transcription PCR and in-situ -hybridization analysis indicated that m-matriptase-2 expression overlaps with the distribution of mouse hepsin (m-hepsin, a cell-surface serine protease identified in hepatoma cells) in adult tissues and during embryonic development. In adult tissues both are expressed at highest levels in liver, kidney and uterus. During embryogenesis m-matriptase-2 expression peaked between days 12.5 and 15.5. m-hepsin expression was biphasic, with peaks at day 7.5 to 8.5 and again between days 12.5 and 15.5. In situ hybridization of embryonic tissues indicated abundant expression of both m-matriptase-2 and m-hepsin in the developing liver and at lower levels in developing pharyngo-tympanic tubes. While m-hepsin was detected in the residual embryonic yolk sac and with lower intensity in lung, heart, gastrointestinal tract, developing kidney tubules and epithelium of the oral cavity, m-matriptase-2 was absent in these tissues, but strongly expressed within the nasal cavity by olfactory epithelial cells. Mechanistic insight into the potential role of this new transmembrane serine protease is provided by its novel expression profile in embryonic and adult mouse.

Amino Acid Sequence↗