POLY-METHYL VINYL ETHER-CO-MALEIC ANHYDRIDE NANOPARTICLES AS ANTIGEN DELIVERY AND ACTIVATING SYSTEMS

The incorporation of antigens into poly-methyl vinyl ether-co-maleic anhydride nanoparticles (NP) has demonstrated to enhance the immune responses in terms of a potent Th1-adjuvant capacity. This fact may be explained by the implemented possibilities that NP render to the antigen: controlled release from the vehicle and chemotaxis for APC recruitment. Besides, after oral administration, it was reported that the bioadhesive nature of the polymer enhanced the interaction of the particulate-adjuvant to the gut mucosa. Moreover, these NP allow the adhesion of antigens and ligands to its outer shell, creating high antigen density surfaces that increase the possibilities of antigen recognition and/or capture by the APCs. Taken together, from the ability of NP to induce potent immune responses our hypothesis was that NP are able to trigger determined elements of the immune system. Explicitly, due to their particulate nature, NPs would interact with APCs, specifically DCs, through PRRs, including TLR. Our results revealed that poly(anhydride) NPs act as agonists of various TLRs (2, 4 and 5), triggering a Th1 profile cytokine release (IFN-γ: 478 pg/mL; IL12: 40 pg/mL) and, after incubation with dendritic cells, induce a 2.5 to 3.5 fold increase of CD54 and CD86 costimulatory molecule expression. Furthermore, in vivo studies suggest that NPs actively elicit a CD8+ T cell response. Taken together our results provide a better understanding of how NPs act as active Th1 adjuvants in immunoprophylaxis and immunotherapy through TLR exploitation. Acknowledgements This work was supported by grants from the Instituto de Salud Carlos III - FIS (PI070326) in Spain. References Arbos P, Wirth M, Arangoa MA, Gabor F, Irache JM. Gantrez AN as a new polymer for the preparation of ligand-nanoparticle conjugates. J Control Release 2002;83(3):321-30. Gomez S, Gamazo C, Roman BS, Ferrer M, Sanz ML, Irache JM. Gantrez AN nanoparticles as an adjuvant for oral immunotherapy with allergens. Vaccine 2007;25(29):5263-71. Irache JM, Salman HH, Gomez S, Espuelas S, Gamazo C. Poly(anhydride) nanoparticles as adjuvants for mucosal vaccination. Frontiers in Bioscience 2009. Ochoa J, Irache JM, Tamayo I, Walz A, DelVecchio VG, Gamazo C. Protective immunity of biodegradable nanoparticle-based vaccine against an experimental challenge with Salmonella Enteritidis in mice. Vaccine 2007;25(22):4410-9. Salman HH, Irache JM, Gamazo C. Immunoadjuvant capacity of flagellin and mannosamine-coated poly(anhydride) nanoparticles in oral vaccination. Vaccine 2009;27(35):4784-90

A methodology for user Interface adaptation of multi-device broadcast-broadband services

New audiovisual experiences involve consuming several contents displayed through multiple internet-connected devices. The TV is still the central hub of the living room, but it is often used simultaneously with other screens. Consequently, the user has the chance to consume all different contents at once across multiple devices. However, no existing adaptation models are available to dynamically adapt such a multitude of contents in multi-device contexts. To address this gap, this paper proposes a novel multi-device adaptation methodology to build adaptive User Interfaces for multi-screen hybrid broadcastbroadband TV experiences. The methodology is extensible to any kind of content, device and user, and is applicable to different contexts considering technological evolution and other fields of application. The proposed methodology is the outcome of extensive research that arose from a previous multi-device media service deployment with broadcasters

Poly(Anhydride) Nanoparticles Act as Active Th1 Adjuvants through Toll-Like Receptor Exploitation

The mechanisms that underlie the potent Th1-adjuvant capacity of poly(methyl vinyl ether-co-maleic anhydride) nanoparticles (NPs) were investigated. Traditionally, polymer NPs have been considered delivery systems that promote a closer interaction between antigen and antigen-presenting cells (APCs). Our results revealed that poly(anhydride) NPs also act as agonists of various Toll-like receptors (TLRs) (TLR2, -4, and -5), triggering a Th1-profile cytokine release (gamma interferon [IFN- ], 478 pg/ml versus 39.6 pg/ml from negative control; interleukin-12 [IL-12], 40 pg/ml versus 7.2 pg/ml from negative control) and, after incubation with dendritic cells, inducing a 2.5- to 3.5-fold increase of CD54 and CD86 costimulatory molecule expression. Furthermore, in vivo studies suggest that NPs actively elicit a CD8 T-cell response. Immunization with empty NPs resulted in a significant delay in the mean survival date (from day 7 until day 23 postchallenge) and a protection level of 30% after challenge against a lethal dose of Salmonella enterica serovar Enteritidis. Taken together, our results provide a better understanding of how NPs act as active Th1 adjuvants in immunoprophylaxis and immunotherapy through TLR exploitation

sPLA2-V inhibits EPCR anticoagulant and antiapoptotic properties by accommodating lysophosphatidylcholine or PAF in the hydrophobic groove

The endothelial protein C receptor (EPCR) plays an important role in cardiovascular disease by binding protein C/activated protein C (APC). EPCR structure contains a hydrophobic groove filled with an unknown phospholipid needed to perform its function. It has not been established whether lipid exchange takes place in EPCR as a regulatory mechanism of its activity. Our objective was to identify this phospholipid and to explore the possibility of lipid exchange as a regulatory mechanism of EPCR activity driven by the endothelially expressed secretory group V phospholipase A2 (sPLA2-V). We identified phosphatidylcholine (PCh) as the major phospholipid bound to human soluble EPCR (sEPCR). PCh in EPCR could be exchanged for lysophosphatidylcholine (lysoPCh) and platelet activating factor (PAF). Remarkably, lysoPCh and PAF impaired the protein C binding ability of sEPCR. Inhibition of sPLA2-V, responsible for lysoPCh and PAF generation, improved APC binding to endothelial cells. EPCR-dependent protein C activation and APC antiapoptotic effect were thus significantly enhanced. In contrast, endothelial cell supplementation with sPLA2-V inhibited both APC generation and its antiapoptotic effects. We conclude that APC generation and function can be modulated by changes in phospholipid occupancy of its endothelial cell receptor

A methodology for user Interface adaptation of multi-device broadcast-broadband services

New audiovisual experiences involve consuming several contents displayed through multiple internet-connected devices. The TV is still the central hub of the living room, but it is often used simultaneously with other screens. Consequently, the user has the chance to consume all different contents at once across multiple devices. However, no existing adaptation models are available to dynamically adapt such a multitude of contents in multi-device contexts. To address this gap, this paper proposes a novel multi-device adaptation methodology to build adaptive User Interfaces for multi-screen hybrid broadcastbroadband TV experiences. The methodology is extensible to any kind of content, device and user, and is applicable to different contexts considering technological evolution and other fields of application. The proposed methodology is the outcome of extensive research that arose from a previous multi-device media service deployment with broadcasters

Poly(Anhydride) Nanoparticles Act as Active Th1 Adjuvants through Toll-Like Receptor Exploitation

The mechanisms that underlie the potent Th1-adjuvant capacity of poly(methyl vinyl ether-co-maleic anhydride) nanoparticles (NPs) were investigated. Traditionally, polymer NPs have been considered delivery systems that promote a closer interaction between antigen and antigen-presenting cells (APCs). Our results revealed that poly(anhydride) NPs also act as agonists of various Toll-like receptors (TLRs) (TLR2, -4, and -5), triggering a Th1-profile cytokine release (gamma interferon [IFN- ], 478 pg/ml versus 39.6 pg/ml from negative control; interleukin-12 [IL-12], 40 pg/ml versus 7.2 pg/ml from negative control) and, after incubation with dendritic cells, inducing a 2.5- to 3.5-fold increase of CD54 and CD86 costimulatory molecule expression. Furthermore, in vivo studies suggest that NPs actively elicit a CD8 T-cell response. Immunization with empty NPs resulted in a significant delay in the mean survival date (from day 7 until day 23 postchallenge) and a protection level of 30% after challenge against a lethal dose of Salmonella enterica serovar Enteritidis. Taken together, our results provide a better understanding of how NPs act as active Th1 adjuvants in immunoprophylaxis and immunotherapy through TLR exploitation

Poly(methyl vinyl ether-co-maleic anhydride) nanoparticles as innate immune system activators

Adjuvant research is being oriented to TLR-agonists, but complement activation has been relatively unexplored. In previous studies it was demonstrated that poly(methyl vinyl ether-co-maleic anhydride) nanoparticles (PVMA NPs) used as adjuvant differentially activate dendritic cells through toll like receptors (TLR) stimulation, however, a high dose of these NPs was used. Now, we demonstrated a dose-response effect, with a concentration as low as 20μg/mL able to stimulate TLR2 and TLR4 transfected dendritic cells. In addition, we investigated whether PVMA NPs are able to exploit also the immunomodulatory benefits of complement activation. Results indicated that the hydroxylated surface of these NPs highly activated the complement cascade, as measured by adsorption studies and a complement fixation bioassay. Stable binding of C3b to NPs was confirmed as indicated by lability to SDS treatment after washing resistance. Complement consumption was confirmed as the lytic capacity of complement exposed to NPs was abolished against antibody-sensitized sheep erythrocytes, with a minimal inhibitory concentration of 50μg NPs, equivalent to a surface of 1cm(2). On the contrary, nanoparticles prepared with poly(lactic-co-glycolic acid) (PLGA), used as a reference, did not consume complement at a concentration ≥3mg NPs (≥40cm(2)). Complement consumption was inhibited when PVMA NPs were cross-linked with diamino groups (1,3-diaminopropane), indicating the role of hydroxyl groups as responsible of the phenomenon. These results favour a model whereby PVMA NPs adjuvant activate complement on site to attract immature antigen presenting cells that are activated through TLR2 and TLR4