2篇
您的检索式：作者名="Lara Moussa"
|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Multispecies probiotic protects gut barrier function in experimental models显示文摘AIM:To investigate the effect of the probiotic combination Lactibiane Tolerance?(LT)on epithelial barrier function in vitro and in vivo.METHODS:The effect of the multispecies probiotic LT was assessed on several models of epithelial barrier function both in vitro(in basal and inflammatory conditions)and in vivo[visceral hypersensitivity induced by chronic stress or by colonic perfusion of a fecal supernatant(FSN)from patients with irritable bowel syndrome(IBS)].In vitro,we measured the permeability of confluent T84 cell monolayers incubated with or without LT by evaluating the paracellular flux of macromolecules,in basal conditions and after stimulation with lipopolysaccharide(LPS)or with conditioned medium of colonic biopsies from IBS patients(IBS-CM).In vivo,male C57/Bl6 mice received orally NaCl or LT for 15 d and were submitted to water avoidance stress(WAS)before evaluating visceral sensitivity by measuring the myoelectrical activity of the abdominal muscle and the paracellular permeability with 51Cr-EDTA.Permeability and sensitivity were also measured after colonic instillation of FSN.Tight-junctions were assessed by immunoblotting and TLR-4 expression was evaluated by immunohistochemistry RESULTS:Incubation of T84 cell monolayers with LT in basal conditions had no significant effect on permeability(P>0.05 vs culture medium).By contrast,addition of LT bacterial bodies(LT)completely prevented the LPS-induced increase in paracellular permeability(P<0.01 vs LPS 10 ng/mL(LPS 10);P<0.01 vs LPS 100ng/mL(LPS 100),P>0.05 vs culture medium).The effect was dose dependent as addition of 109 LT bacterial bodies induced a stronger decrease in absorbance than 106 LT(109 LT+LPS 10:-20.1%±13.4,P<0.01vs LPS 10;106 LT+LPS 10:-11.6%±6.2,P<0.01 vs LPS 10;109 LT+LPS 100:-14.4%±5.5,P<0.01 vs LPS 100;106 LT+LPS 100:-11.6%±7.3,P<0.05 vs LPS 100).Moreover,the increase in paracellular permeability induced by culturing T84 cells with conditioned medium of colonic biopsies from IBS patients(IBS-CM)was completely inhibited in the presence of 109 LT(P<0.01 vs IBS-CM).LT also significantly prevented the epithelial disruption induced by intracolonic infusion of fecal supernatant from IBS patients(P<0.01 vs IBS FSN)or water avoidance stress P<0.01 vs WAS)in C57/Bl6 mice and increased the expression of occludin in vitro and in vivo,as assessed by immnunoblotting.The WAS-induced effect on visceral sensitivity was prevented by LT treatment since values obtained for all steps of colorectal distension were significantly(P<0.01)different from the WAS group.Finally,LT downregulated the response mediated through TLR-4 in vitro(decrease in tumor necrosis factorαsecretion in response to LPS:-65.8%for 109 LT and-52.5%for 106LT,P<0.01 vs LPS)and in vivo(inhibition of WAS induced an increase in TLR-4 expression in the LT treated mice colon,P<0.01 vs WAS).CONCLUSION:The probiotic LT mix prevented the disruption to the epithelial barrier induced by LPS,stress or colonic soluble factors from IBS patients and prevented visceral hypersensitivity. | Mylene Nébot-Vivinus Cherryl Harkat Hanene Bzioueche Christel Cartier Raffaella Plichon-Dainese Lara Moussa Helene Eutamene Dorsa Pishvaie Sophie Holowacz Christian Seyrig Thierry Piche Vassilia Theodorou | 2014 | World Journal of Gastroenterology2014，20，22： | 12 |
| 2 | Embedding MSCs in Si-HPMC hydrogel decreased MSC-directed host immune response and increased the regenerative potential of macrophages显示文摘Embedding mesenchymal stromal cells(MSCs)in biomaterial is a subject of increasing interest in the field of Regenerative Medicine.Speeding up the clinical use of MSCs is dependent on the use of non-syngeneic models in accordance with Good Manufacturing Practices(GMP)requirements and on costs.To this end,in this study,we analyzed the in vivo host immune response following local injection of silanized hydroxypropyl methylcellulose(Si-HPMC)-embedded human MSCs in a rat model developing colorectal damage induced by ionizing radiation.Plasma and lymphocytes from mesenteric lymph nodes were harvested in addition to colonic tissue.We set up tests,using flow cytometry and a live imaging system,to highlight the response to specific antibodies and measure the cytotoxicity of lymphocytes against injected MSCs.We demonstrated that Si-HPMC protects MSCs from specific antibodies production and from apoptosis by lymphocytes.We also observed that Si-HPMC does not modify innate immune response infiltrate in vivo,and that in vitro co-culture of Si-HPMC-embedded MSCs impacts macrophage inflammatory response depending on the microenvironment but,more importantly,increases the macrophage regenerative response through Wnt-family and VEGF gene expression.This study furthers our understanding of the mechanisms involved,with a view to improving the therapeutic benefits of biomaterial-assisted cell therapy by modulating the host immune response.The decrease in specific immune response against injected MSCs protected by Si-HPMC also opens up new possibilities for allogeneic clinical use. | Christelle Demarquay Lara Moussa Gildas Réethorée Fabien Milliat Pierre Weiss Noëlle Mathieu | 2022 | Regenerative Biomaterials2022，9，1： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员