Luciferase-based reporting of suicide gene activity in murine mesenchymal stem cells

© 2019 Gerace et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Due to their ease of isolation, gene modification and tumor-homing properties, mesenchymal stem cells (MSCs) are an attractive cellular vehicle for the delivery of toxic suicide genes to a variety of cancers in pre-clinical models. In addition, the incorporation of suicide genes in stem cell-derived cell replacement therapies improves their safety profile by permitting graft destruction in the event of unexpected tumorigeneses or unwanted differentiation. Due to the functional requirement of ATP for the Firefly luciferase gene Luc2 to produce light, luciferase-based reporting of cytotoxicity can be engineered into potential cell therapies. Consequently, we nucleofected mammalian expression plasmids containing both the Luc2 and the yeast fusion cytosine deaminase uracil phosphoribosyltransferase (CDUPRT) genes for expression in murine MSCs to assess luciferase as a reporter of suicide gene cytotoxicity, and MSC as vehicles of suicide gene therapy. In vitro bioluminescence imaging (BLI) showed that following the addition of the non-toxic prodrug fluorocytosine (5-FC), CDUPRT-expressing MSCs displayed enhanced cytotoxicity in comparison to Luc2 reporter MSC controls. This study demonstrates the utility of luciferase as a reporter of CDUPRT-mediated cytotoxicity in murine MSC using BLI

Restrictions on Access to Social Protection by New Southern European Migrants in Belgium

peer reviewedDespite the fact that the global financial crisis has affected Belgium’s economic performance, the country has continued to be an attractive destination for migrants. Recently, however, there has been a dramatic change in migrant flows to Belgium, as a result of two phenomena. First and foremost, the country has experienced large inflows of post-accession migration from Central and Eastern European citizens. Second, 40 years after the end of the guest worker programmes, the economic crisis reactivated migration from Southern Europe. One important consequence of the economic crisis and the arrival of Central and Eastern European migrants has been the growing scepticism that has developed in Belgium towards the freedom of circulation. This has led the authorities to implement specific policies aimed at discouraging further migration of low-skilled EU migrants, who are deemed undesirable. In this chapter, we analyse a specific policy consisting of the removal of residence permits from EU jobseekers who claim social security benefits in Belgium. This policy has affected both Central and Eastern European as well as new Southern European EU migrants.Examining the mobilization of different organizations, we then show that—while they are numerically fewer—new Southern European immigrants are in a better position than other new immigrants in Belgium to challenge receiving country policies that target them

Eurocity London: a qualitative comparison of graduate migration from Germany, Italy and Latvia

This paper compares the motivations and characteristics of the recent migration to London of young-adult graduates from Germany, Italy and Latvia. Conceptually the paper links three domains: the theory of core–periphery structures within Europe; the notion of London as both a global city and a ‘Eurocity’; and the trope of ‘crisis’. The dataset analysed consists of 95 in-depth biographical interviews and the paper’s main objective is to tease out the narrative similarities and differences between the three groups interviewed. Each of the three nationalities represents a different geo-economic positioning within Europe. German graduates move from one economically prosperous country to another; they traverse shallow economic and cultural boundaries. Italian graduates migrate from a relatively peripheral Southern European country where, especially in Southern Italy, employment and career prospects have long been difficult, and have become more so in the wake of the financial crisis. They find employment opportunities in London which are unavailable to them in Italy. Latvian graduates are from a different European periphery, the Eastern one, post-socialist and post-Soviet. Like the Italians, their moves are economically driven whereas, for the Germans, migration is more related to lifestyle and life-stage. For all three groups, the chance to live in a large, multicultural, cosmopolitan city is a great attraction. And for all groups, thoughts about the future are marked by uncertainty and ambiguity

Effect of expression of adenine phosphoribosyltransferase on the in vivo anti-tumor activity of prodrugs activated by E. coli purine nucleoside phosphorylase

The use of E. coli purine nucleoside phosphorylase (PNP) to activate prodrugs has demonstrated excellent activity in the treatment of various human tumor xenografts in mice. E. coli PNP cleaves purine nucleoside analogs to generate toxic adenine analogs, which are activated by adenine phosphoribosyl transferase (APRT) to metabolites that inhibit RNA and protein synthesis. We created tumor cell lines that encode both E. coli PNP and excess levels of human APRT, and have used these new cell models to test the hypothesis that treatment of otherwise refractory human tumors could be enhanced by overexpression of APRT. In vivo studies with 6-methylpurine-2′-deoxyriboside (MeP-dR), 2-F-2′-deoxyadenosine (F-dAdo) or 9-β-D-arabinofuranosyl-2-fluoroadenine 5′-monophosphate (F-araAMP) indicated that increased APRT in human tumor cells coexpressing E. coli PNP did not enhance either the activation or the anti-tumor activity of any of the three prodrugs. Interestingly, expression of excess APRT in bystander cells improved the activity of MeP-dR, but diminished the activity of F-araAMP. In vitro studies indicated that increasing the expression of APRT in the cells did not significantly increase the activation of MeP. These results provide insight into the mechanism of bystander killing of the E. coli PNP strategy, and suggest ways to enhance the approach that are independent of APRT

Deconstruyendo al inmigrante latinoamericano: las políticas migratorias ibéricas como tecnologías neocoloniales

Resumen Las migraciones latinoamericanas hacia la Península Ibérica han experimentado un fuerte crecimiento durante las dos últimas décadas. En este contexto, los estados español y portugués han implementado políticas que construyen al inmigrante latinoamericano como un extranjero excepcional, subrayando una supuesta compatibilidad cultural como garantía de una mejor integración social en la sociedad receptora. El tratamiento político y legal diferenciado hacia esta población entronca así con un discurso que enfatiza la importancia de los vínculos históricos y culturales que unen a Latinoamérica y a la Península Ibérica desde hace cinco siglos. Partiendo de las teorías decoloniales, este trabajo aborda de manera comparada la evolución de este discurso político-legal en España y Portugal a lo largo de los últimos veinte años, prestando especial atención tanto a sus manifestaciones concretas en leyes y políticas públicas como a los distintos momentos en que ha sido adoptado, mantenido y abandonado en función de las circunstancias

Community planning and urban design in contested places. Some insights from Belfast

Although social conflict due to the presence of different groups divided by cultural, religious or ethnic issues plagues many contemporary cities, community and participatory planning methods still pay little attention to segregation in contested spaces as a specific matter of concern. This paper aims to contribute to filling this gap through the development of a novel tool to be implemented during community planning processes in contested cities, particularly in (visual) mapping processes. The pilot area for developing the lexicon has been selected within the city of Belfast, which has been struggling for years with problems related to inter-religious sectarian conflicts. The material effects on the urban structure of the long process of defensive planning during the socalled Troubles and within the post-conflicts peace programmes have been investigated by analysing urban artefacts including edges, borders, barriers, doors, visual control points. The paper suggests that a simple, recognizable lexicon may contribute to honing community planning methods in contested places by integrating the traditional methodology of visual mapping with a tailored taxonomy of elements of urban conflict, which may be used at many stages of the planning process, including developing a visual map, design and planning, and developing and implementing an action plan