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Background & Aims: Immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX; OMIM 304930) syndrome is a congenital syndrome characterized by autoimmune enteropathy, endocrinopathy, dermatitis, and other autoimmune phenomena. In the present work, we aimed to uncover the molecular basis of a distinct form of IPEX syndrome presenting at the edge of autoimmunity and severe allergy. Methods: The FOXP3 gene was sequenced, FOXP3 messenger RNA (mRNA) was quantified by real-time polymerase chain reaction (PCR), and protein expression in peripheral blood lymphocytes was analyzed by flow cytometry after intracellular staining. In coculture experiments (CD4+CD25− and CD4+CD25+ cells), the functions of regulatory T cells were analyzed. Expression of interferon γ and interleukin 2 and 4 mRNA within the inflamed intestinal mucosa was quantified by real-time PCR. Results: Here, we describe a distinct familial form of IPEX syndrome that combines autoimmune and allergic manifestations including severe enteropathy, food allergies, atopic dermatitis, hyper-IgE, and eosinophilia. We have identified a 1388-base pair deletion (g.del−6247_−4859) of the FOXP3 gene encompassing a portion of an upstream noncoding exon (exon −1) and the adjacent intron (intron −1). This deletion impairs mRNA splicing, resulting in accumulation of unspliced pre-mRNA and alternatively spliced mRNA. This causes low FOXP3 mRNA levels and markedly decreased protein expression in peripheral blood lymphocytes of affected patients. Numbers of CD4+CD25+FOXP3+ regulatory T cells are extremely low, and the CD4+CD25+ T cells that are present exhibit little regulatory function. Conclusions: A new mutation within an upstream noncoding region of FOXP3 results in a variant of IPEX syndrome associating autoimmune and severe immunoallergic symptoms. [Copyright &y& Elsevier]

Purpose: Papillomavirus (HPV)-16 infection has been recently associated with oropharyngeal head and neck cancers (HNCs) that express the E6 and E7 oncoproteins. The licensed vaccines are efficient for the prevention of HPV infection, but not for established tumors. Therefore innovative therapeutic vaccines targeting HPV oncogenes are required. Previously, we have developed a DNA-based vaccine strategy using plasmo-VLP carrying a non-oncogenic mutated, but immunogenic, form of E7 from HPV16 (pVLP-E7). pVLPs allow to form in vivo VLPs (viral-like particles formed by structural proteins devoid of viral genome). Thus, we showed that pVLP-E7 can elicit specific anti-E7 immune responses and cure mice from E6/E7 HPV16-positive tumors injected subscutaneously in the flank of animals. The present study aims at developing an orthotopic model of HNCs in mice as a pre-clinical model. Material and methods: TC-1 tumor cells, an epithelial murine cell line that express E6 and E7 of HPV 16, were injected into the tongue or cheek (orthotopic models) or in the flank (ectopic model) of C57BL/6 mice; different routes of vaccination (intranasal, intra-cheek or intradermal) with pVLP-E7 were tested in order to induce local and systemic immune responses; tumor growth, anti-E7 immune responses, and anti-tumor effects against established tumors were compared between the different tumor models and routes of vaccination. Results: The cheek model was better suited for future test of immunization than intralingual or subcutaneous tumor models, due to better survival rates and slower growth kinetics. Intradermal vaccination with pVLP-E7 was the better route of administration to achieve a systemic anti-E7 T-cell response. Interestingly, intradermal and intra-cheek vaccinations appeared to be both equally efficient to stimulate local immune responses as well as anti-tumoral responses by using the orthotopic model. Conclusions: DNA vaccinations with pVLP-E7 can induce therapeutic anti-tumoral effects using an intra-cheek orthotopic model of HPV-induced HNCs. [Copyright &y& Elsevier]

Vascular smooth muscle cell (VSMC) trans-differentiation, or their switch from a contractile/quiescent to a secretory/inflammatory/ migratory state, is known to play an important role in pathological vascular remodeling including atherosclerosis and postangioplasty restenosis. Several reports have established the Notch pathway as tightly regulating VSMC response to various stress factors through growth, migration, apoptosis, and de-differentiation. More recently, we showed that alterations of the Notch pathway also govern VSMC acquisition of the inflammatory state, one of the major events accelerating atherosclerosis. We also evidenced that the inflammatory context of atherosclerosis triggers a de novo expression of adenylyl cyclase isoform 8 (AC8), associated with the properties developed by trans-differentiated VSMCs. As an initial approach to understanding the regulation of AC8 expression, we examined the role of the Notch pathway. Here we show that inhibiting the Notch pathway enhances the effect of IL1β on AC8 expression, amplifies its deleterious effects on the VSMC trans-differentiated phenotype, and decreases Notch target genes Hrt1 and Hrt3. Conversely, Notch activation resulted in blocking AC8 expression and up-regulated Hrt1 and Hrt3 expression. Furthermore, overexpressing Hrt1 and Hrt3 significantly decreased IL1β-induced AC8 expression. In agreement with these in vitro findings, the in vivo rat carotid balloon-injury model of restenosis evidenced that AC8 de novo expression coincided with down-regulation of the Notch3 pathway. These results, demonstrating that the Notch pathway attenuates IL1β-mediated AC8 up-regulation in trans-differentiated VSMCs, suggest that AC8 expression, besides being induced by the proinflammatory cytokine IL1β, is also dependent on down-regulation of the Notch pathway occurring in an inflammatory context. [ABSTRACT FROM AUTHOR]

Mannose Receptor (MR) and DC-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN) are two mannose-specific targets for antigens carried by liposomes but DC-SIGN is more specific of DCs. Here, DC targeting is addressed by using DPPC/DOPE liposomes decorated with a series of diether lipids with a polar head of either a mannose (Man), tri-antenna of α- d -mannopyranoside (Tri-Man), [Manα1-3(Manα1-6)Man] (Man-tri), pseudo-Man 4 (PMan 4) or pseudo-Man 5 (PMan 5). Liposomes decorated with Man-Tri show the highest binding and internalization in cells expressing DC-SIGN and in human monocytes-derived DCs. Conversely, cells expressing MR bind and take up Tri-Man liposomes 3-fold higher than Man-tri liposomes. Comparatively, liposomes decorated with PMan 4 and PMan 5 do not show any advantages. Overall, the results indicate that liposomes decorated with Man-tri residues are more selective toward DCs than those with Tri-Man thanks to better recognition by DC-SIGN. Image 1 • Liposomes decorated with Man-Tri show higher binding and internalization than Tri-Man liposomes in cells expressing DC-SIGN. • Conversely, cells expressing MR bind and take up Tri-Man liposomes 3-fold higher than Man-tri liposomes. • Thus, liposomes decorated with Man-tri residues would be more selective than Tri-Man to target DCs. [ABSTRACT FROM AUTHOR]