References of "Maertens, Ludovic"
     in
Bookmark and Share    
Full Text
See detailLymphangiogenesis and extracellular matrix remodeling
Erpicum, Charlotte ULg; Detry, Benoît ULg; Paupert, Jenny ULg et al

Conference (2013, January 28)

Detailed reference viewed: 28 (6 ULg)
Full Text
Peer Reviewed
See detailSunitinib inhibits inflammatory corneal lymphangiogenesis.
Detry, Benoît ULg; Blacher, Silvia ULg; Erpicum, Charlotte ULg et al

in Investigative Ophthalmology & Visual Science (2013), 54(5), 3082-93

PURPOSE: To evaluate the antilymphangiogenic potential of multi-target tyrosine kinase inhibitor sunitinib in corneal neovascularization (NV). METHODS: Inflammatory corneal NV was induced by thermal ... [more ▼]

PURPOSE: To evaluate the antilymphangiogenic potential of multi-target tyrosine kinase inhibitor sunitinib in corneal neovascularization (NV). METHODS: Inflammatory corneal NV was induced by thermal cauterization applied in the central cornea of mice, to which sunitinib malate was daily administered by gavage or not. At days 6, 11, or 17 post cauterization, lymphatic and blood vessels, as well as inflammatory cells were immunostained and quantified in whole-mounted corneas. RT-PCRs were performed to evidence VEGF-A, VEGF-C, VEGF-D, placental growth factor (PlGF), and soluble vascular endothelial growth factor receptor (VEGFR)-1 and -2 (sVEGFR-1, sVEGFR-2) expressions. Macrophages were isolated from mice peritoneal cavity following thioglycollate injection to produce conditioned medium. The effects of sunitinib were evaluated in vitro in the aortic and lymphatic ring assays in the presence or not of macrophage conditioned medium. RESULTS: Sunitinib treatment drastically reduced pathologic corneal lymphangiogenesis and angiogenesis. Reduced F4/80+ cell infiltration was evidenced in sunitinib-treated mice and was associated to decreased VEGF-A (by 50%, P < 0.01) and VEGF-C (by 35%, P < 0.01) expressions, while VEGF-D and sVEGFR-2 expressions were not affected. In vitro, sunitinib dose-dependently inhibited aortic ring outgrowth, but failed to affect lymphangiogenesis in the lymphatic ring assay. However, macrophage conditioned medium-enhanced angiogenesis and lymphangiogenesis were both strongly counteracted by sunitinib treatment. Mechanistically, sunitinib blocked VEGFR-2 phosphorylation induced by VEGF-A released by macrophages. CONCLUSIONS: Sunitinib exerts antihemangiogenic and antilymphangiogenic effects in vivo by reducing F4/80+ cell recruitment and interacting with their released factors. [less ▲]

Detailed reference viewed: 18 (6 ULg)
Full Text
Peer Reviewed
See detailTargeting a single function of the multifunctional matrix metalloprotease MT1-MMP. Impact on lymphangiogenesis.
Ingvarsen, Signe; Porse, Astrid; Erpicum, Charlotte ULg et al

in Journal of Biological Chemistry (2013), sous presse

The group of matrix metalloproteases (MMPs) is responsible for multiple processes of extracellular matrix remodeling in the healthy body but also for matrix and tissue destruction during cancer invasion ... [more ▼]

The group of matrix metalloproteases (MMPs) is responsible for multiple processes of extracellular matrix remodeling in the healthy body but also for matrix and tissue destruction during cancer invasion and metastasis. The understanding of the contributions from each individual MMP, both in healthy and pathological events, has been complicated by the lack of specific inhibitors and the fact that some of the potent MMPs are multifunctional enzymes. These factors have also hampered the setup of therapeutic strategies targeting MMP activity. A tempting target is the membrane-associated MT1-MMP which has well-documented importance in matrix degradation but which takes part in more than one pathway in this regard. In this report, we describe the selective targeting of a single function of this enzyme by means of a specific monoclonal antibody against MT1-MMP, raised in an MT1-MMP knock-out mouse. The antibody blocks the enzyme ability to activate proMMP-2 without interfering with the collagenolytic function or the general proteolytic activity of MT1-MMP. Using this antibody, we have shown that the MT1-MMP-catalyzed activation of proMMP- 2 is involved in the outgrowth of cultured lymphatic endothelial cells in a collagen matrix in vitro, as well as in lymphatic vessel sprouting assayed ex vivo. This is the first example of the complete inactivation of a single function of a multifunctional MMP and the use of this strategy to pursue its role. [less ▲]

Detailed reference viewed: 15 (5 ULg)
Full Text
Peer Reviewed
See detailBone Marrow-derived Myofibroblasts Are the Providers of Pro-invasive Matrix Metalloproteinase 13 in Primary Tumor.
Lecomte, Julie ULg; Masset, Anne; Blacher, Silvia ULg et al

in Neoplasia : An International Journal for Oncology Research (2012), 14(10), 943-51

Carcinoma-associated fibroblasts are key contributors of the tumor microenvironment that regulates carcinoma progression. They consist of a heterogeneous cell population with diverse origins, phenotypes ... [more ▼]

Carcinoma-associated fibroblasts are key contributors of the tumor microenvironment that regulates carcinoma progression. They consist of a heterogeneous cell population with diverse origins, phenotypes, and functions. In the present report, we have explored the contribution of bone marrow (BM)-derived cells to generate different fibroblast subsets that putatively produce the matrix metalloproteinase 13 (MMP13) and affect cancer cell invasion. A murine model of skin carcinoma was applied to mice, irradiated, and engrafted with BM isolated from green fluorescent protein (GFP) transgenic mice. We provide evidence that one third of BM-derived GFP(+) cells infiltrating the tumor expressed the chondroitin sulfate proteoglycan NG2 (pericytic marker) or alpha-smooth muscle actin (alpha-SMA, myofibroblast marker), whereas almost 90% of Thy1(+) fibroblasts were originating from resident GFP-negative cells. MMP13producing cells were exclusively alpha-SMA(+) cells and derived from GFP(+) BM cells. To investigate their impact on tumor invasion, we isolated mesenchymal stem cells (MSCs) from the BM of wild-type and MMP13-deficient mice. Wild-type MSC promoted cancer cell invasion in a spheroid assay, whereas MSCs obtained from MMP13-deficient mice failed to. Our data support the concept of fibroblast subset specialization with BM-derived alpha-SMA(+) cells being the main source of MMP13, a stromal mediator of cancer cell invasion. [less ▲]

Detailed reference viewed: 39 (14 ULg)
Full Text
Peer Reviewed
See detailNebulized Anti-IL-13 Monoclonal Antibody Fab' Fragment Reduces Allergen-Induced Asthma
Hacha, Jonathan ULg; Tomlinson, K; Maertens, Ludovic ULg et al

in American Journal of Respiratory Cell and Molecular Biology (2012), sous presse

Rationale: Interleukin-13 (IL-13) is a prototypic Th2 cytokine and a central mediator of the complex cascade of events leading to asthmatic phenotype. Indeed, IL-13 plays key roles in IgE synthesis ... [more ▼]

Rationale: Interleukin-13 (IL-13) is a prototypic Th2 cytokine and a central mediator of the complex cascade of events leading to asthmatic phenotype. Indeed, IL-13 plays key roles in IgE synthesis, bronchial hyperresponsiveness, mucus hypersecretion, subepithelial fibrosis and eosinophil infiltration. Objectives: We assessed the potential efficacy of inhaled anti-IL-13 monoclonal antibody Fab' fragment on allergen-induced airway inflammation, hyperresponsiveness and remodeling in an experimental model of allergic asthma. Anti-IL-13 Fab' was administered to mice as a liquid aerosol generated by inExpose® inhalation system in a tower allowing a nose-only exposure. Methods: BALB/c mice were treated by PBS, anti-IL-13 Fab' or A33 Fab' fragment and subjected to ovalbumin (OVA) exposure for 1 and 5 weeks (short term (ST) and long term (LT) protocols). Measurements and Main Results: Our data demonstrate a significant anti-asthma effect following nebulization of anti-IL-13 Fab' in a model of asthma driven by allergen exposure as compared to saline and non-immune Fab fragments. In short and long terms protocols, administration of the anti-IL-13 Fab' by inhalation significantly decreased bronchial responsiveness to methacholine, BALF eosinophilia, inflammatory cell infiltration in lung tissue, and many features of airway remodeling. Levels of pro-inflammatory mediators and matrix metalloprotease levels were significantly lower in lung parenchyma of mice treated with anti-IL-13 Fab'. Conclusions: These data demonstrate that an inhaled anti-IL-13 Fab' significantly reduces airway inflammation, hyperresponsiveness and remodeling. Specific neutralization of IL-13 in the lungs using an inhaled anti-IL-13 Fab' could represent a novel and effective therapy for the treatment of asthma. [less ▲]

Detailed reference viewed: 86 (7 ULg)