Biomedical nanoparticles modulate specific CD4+ T cell stimulation by inhibition of antigen processing in dendritic cells

Understanding how nanoparticles may affect immune responses is an essential prerequisite to developing novel clinical applications. To investigate nanoparticle-dependent outcomes on immune responses, dendritic cells (DCs) were treated with model biomedical poly(vinylalcohol)-coated super-paramagnetic iron oxide nanoparticles (PVA-SPIONs). PVA-SPIONs uptake by human monocyte-derived DCs (MDDCs) was analyzed by flow cytometry (FACS) and advanced imaging techniques. Viability, activation, function, and stimulatory capacity of MDDCs were assessed by FACS and an in vitro CD4+ T cell assay. PVA-SPION uptake was dose-dependent, decreased by lipopolysaccharide (LPS)-induced MDDC maturation at higher particle concentrations, and was inhibited by cytochalasin D pre-treatment. PVA-SPIONs did not alter surface marker expression (CD80, CD83, CD86, myeloid/plasmacytoid DC markers) or antigen-uptake, but decreased the capacity of MDDCs to process antigen, stimulate CD4+ T cells, and induce cytokines. The decreased antigen processing and CD4+ T cell stimulation capability of MDDCs following PVA-SPION treatment suggests that MDDCs may revert to a more functionally immature state following particle exposure.

The Nightmare of Actual Identity": Franco-Algerian Literature after Liberation"

In this thesis I examine the issues of postcolonial Algerian identity expressed in literature, and the difficulty of defining an Algerian identity independent of French influence. I analyze and contextualize three novels (Le Polygone etoile by Kateb Yacine,L'Amour, la fantasia by Assia Djebar, and Le Village de l'allemand ou le journal des freres Schiller) representative of their respective periods. I explore the evolution of expressions of identity through post-liberation Algeria. The years immediately following decolonization are marked by the effort to return to aprecolonial blank slate, an effort that Yacine cautions against. The 1980s and 1990s are most concerned with re-inserting Algeria into the Western historical discourse, and the most recent literature moves beyond decolonization to discuss the current Islamistchallenge and immigration. Among the pertinent issues are language, oral vs. written traditions, the often blatant absence of Algerians and women from the accounts in the French colonial archives, and, of course, the Self/Other binary. I have found that theserepresentative authors and texts use asynchronic time, fragmented narrative, re-written history, and expressions of violence in an attempt to cope with the colonial period and decolonization. I show that these authors provide a commentary on those who have triedto erase their French side, but with little success. Ultimately, though in different ways, each author writes that Algerians much accept their French past and move beyond it,rather than fighting their collective history.