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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Inhibition of IL-17-committed T cells in a murine psoriasis model by a vitamin D analogue / マウス乾癬モデルにおいてビタミンD誘導体はIL-17産生能を有するT細胞を抑制する

Kusuba, Nobuhiro 23 July 2019 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第22000号 / 医博第4514号 / 新制||医||1038(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 生田 宏一, 教授 竹内 理, 教授 杉田 昌彦 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
22

Papel dos receptores do tipo Toll na morte celular induzida por ativação (AICD) de linfócitos T. / Role of Toll-Like receptors in the activation-induced cell death (AICD) of T cells hybridoma.

Pernavia, Maira Macedo de Sant\'Anna 26 October 2009 (has links)
Durante uma infecção o número de linfócitos T aumenta dramaticamente. A fase de expansão clonal é seguida pela redução do nível de células T ativadas que depende, em parte, de um processo de morte celular induzida por ativação (AICD). Nosso grupo mostrou que APCs quando são estimuladas com LPS, um agonista de TLR4, produzem PGE2, que inibe a AICD de linfócitos T CD4+ através da supressão da expressão de CD95L (Weinlich et al, 2008). Porém, os efeitos da estimulação direta de TLR nos linfócitos T sobre o processo de AICD foram pouco elucidados. Sendo assim, o projeto tem como objetivo verificar se a estimulação dos diversos TLRs com seus agonistas é capaz de modular a AICD de hibridomas de linfócito T DO11.10. Inicialmente, demonstramos que este hibridoma expressa os TLR1, 2, 3, 4, 5, 6, 7, 9 e 11. Dentre todos os agonistas utilizados somente o Imiquimod, um agonista de TLR7, reduziu a morte celular quando adicionado durante a indução de AICD. O efeito protetor desse agonista foi através da inibição da expressão de CD95L, tanto no nível de mRNA quanto protéico. / During an infection the number of T lymphocytes increases dramatically. The clonal expansion phase is followed by reducing the level of activated T cells that depends, in part, a process of cell death induced by activation (AICD). Our group showed that when APCs are stimulated with LPS, a TLR4 agonist, produce PGE2, which inhibits the AICD of CD4 + T cells by suppressing the expression of CD95L (Weinlich et al, 2008). However, the effects of direct stimulation of TLR on T cells on the process of AICD were little explained. Therefore, the project aims to determine whether the stimulation of different TLRs to their agonist is able to modulate AICD of T lymphocyte hybridoma DO11.10. Initially, we demonstrated that this hybridoma expresses TLR1, 2, 3, 4, 5, 6, 7, 9 and 11. Among all agonists used only imiquimod, a TLR7 agonist, reduced cell death when added during the induction of AICD. The protective effect of this agonist was by inhibiting the expression of CD95L, both at the mRNA and protein.
23

Papel dos receptores do tipo Toll na morte celular induzida por ativação (AICD) de linfócitos T. / Role of Toll-Like receptors in the activation-induced cell death (AICD) of T cells hybridoma.

Maira Macedo de Sant\'Anna Pernavia 26 October 2009 (has links)
Durante uma infecção o número de linfócitos T aumenta dramaticamente. A fase de expansão clonal é seguida pela redução do nível de células T ativadas que depende, em parte, de um processo de morte celular induzida por ativação (AICD). Nosso grupo mostrou que APCs quando são estimuladas com LPS, um agonista de TLR4, produzem PGE2, que inibe a AICD de linfócitos T CD4+ através da supressão da expressão de CD95L (Weinlich et al, 2008). Porém, os efeitos da estimulação direta de TLR nos linfócitos T sobre o processo de AICD foram pouco elucidados. Sendo assim, o projeto tem como objetivo verificar se a estimulação dos diversos TLRs com seus agonistas é capaz de modular a AICD de hibridomas de linfócito T DO11.10. Inicialmente, demonstramos que este hibridoma expressa os TLR1, 2, 3, 4, 5, 6, 7, 9 e 11. Dentre todos os agonistas utilizados somente o Imiquimod, um agonista de TLR7, reduziu a morte celular quando adicionado durante a indução de AICD. O efeito protetor desse agonista foi através da inibição da expressão de CD95L, tanto no nível de mRNA quanto protéico. / During an infection the number of T lymphocytes increases dramatically. The clonal expansion phase is followed by reducing the level of activated T cells that depends, in part, a process of cell death induced by activation (AICD). Our group showed that when APCs are stimulated with LPS, a TLR4 agonist, produce PGE2, which inhibits the AICD of CD4 + T cells by suppressing the expression of CD95L (Weinlich et al, 2008). However, the effects of direct stimulation of TLR on T cells on the process of AICD were little explained. Therefore, the project aims to determine whether the stimulation of different TLRs to their agonist is able to modulate AICD of T lymphocyte hybridoma DO11.10. Initially, we demonstrated that this hybridoma expresses TLR1, 2, 3, 4, 5, 6, 7, 9 and 11. Among all agonists used only imiquimod, a TLR7 agonist, reduced cell death when added during the induction of AICD. The protective effect of this agonist was by inhibiting the expression of CD95L, both at the mRNA and protein.
24

Formulace a (trans)dermální podání imiquimodu / Formulation and (trans)dermal delivery of imiquimod

Hladký, Pavel January 2018 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Candidate: Pavel Hladký Consultant: PharmDr. Barbora Švecová, Ph.D. Title of Thesis: Formulation and (trans)dermal application of imiquimod Imiquimod (IMQ) is an active pharmaceutical substance which belongs to the group of heterocyclic imidazoquinolines. The mechanism of its effect is an induction of cellular immune response after topical administration, that is used for a treatment of tumors or viral diseases of the skin. In the Czech Republic it is available like a cream called Aldara® , the content of IMQ is 5 %. Although Aldara® is an effective medicine, many problems are associated with its use, especially high price, undesirable effects, disposable use, environmental pollution, etc. The aim of this work was to prepare new liposomes for topical administration containing lower ammount of IMQ (0.5 %) and evaluation of penetration of IMQ into human skin in vitro. To improve the entrance of the drug into the skin transdermal penetration enhancers were used. Permeation experiments were performed in Franz diffusion cells on human skin under conditions as close as possible to the physiological environment of the organism. Subsequently, the individual layers of the skin (stratum corneum, the epidermis,...
25

Deciphering the role of c-Jun N-Terminal Kinase (JNK1) in an in vivo model of skin inflammation

Le, Aurore 01 December 2020 (has links) (PDF)
JNK1 (c-Jun N-terminal kinase 1) has been studied in numerous biological phenomena, but its role in skin inflammation diseases has not been fully defined yet. We therefore evaluated the role of JNK1 in imiquimod-induced dermatitis, a classical model that shares many features with human psoriasis. We showed that JNK1 was necessary for the expression of inflammatory markers and for acanthosis induced by imiquimod. We demonstrated that the loss of JNK1 in dendritic cells or myeloid cells reduced inflammatory markers but did not affect acanthosis induced by imiquimod. In vitro experiments in bone marrow-derived macrophages (BMMs) supported the role of JNK1 in the activation of the inflammasome pathway by the Aldara® cream. Next, we observed that the loss of JNK1 in keratinocytes did not reduce imiquimod-induced expression of most inflammatory markers but acanthosis and proliferation of epidermal cells was decreased. To better understand the role of JNK1 in keratinocytes, we evaluated the transcriptome and the epigenomic landscape of JNK1-deficient epidermal cells from mice treated with imiquimod. These data highlighted the potential role of JNK1 downstream of the EGFR pathway. We further observed that the inhibition of the EGFR pathway decreased imiquimod-induced acanthosis. Our work shows the dual role of JNK1 in skin inflammation induced by imiquimod. On one hand, JNK1 influences the expression of inflammatory mediators by myeloid cells, probably through the inflammasome pathway. On the other hand, JNK1 modulates the response of keratinocytes to EGFR ligands. Taken together, these data suggest that JNK1 could represent a valuable therapeutic target for the management of psoriasis. / Doctorat en Sciences médicales (Médecine) / info:eu-repo/semantics/nonPublished
26

Effets de la stimulation des cellules de leucémie lymphoïde chronique via TLR-7 et TLR-9 / Functions of TLR-7 and TLR-9 on tumor cells of chronic lymphocytic leukemia

Chen, Min 08 April 2013 (has links)
La leucémie lymphoïde chronique (LLC), caractérisée par une résistance à l'apoptose in vivo et par la faible immunogénicité des cellules leucémiques est une maladie de présentation hétérogène. L'immunochimiothérapie a permis de progresser dans son traitement, mais l'identification de nouvelles cibles d'immunothérapie serait souhaitable. Dans ce contexte, la présence de TLR-7 et TLR-9 sur les cellules de LLC est une piste intéressante. L'objectif principal de cette étude était ainsi de préciser les effets in vitro de l'engagement de TLR-7 et TLR-9 sur les cellules tumorales par leur ligands respectifs Imiquimod R837 et ODN CpG M362. Ces effets ont été examinés sur des LLC classées en formes cliniques et/ou selon leur statut mutationnel IgVH. Les cellules séparées de 40 patients ont été cultivées pendant trois jours, avec du milieu seul, de l'acétate phorbolmyristate (PMA) ou d'Imiquimod ou d'ODN. La cytométrie en flux a permis d'étudier l'expression des TLRs et d'antigènes de différenciation au niveau des cellules B tumorales, d'évaluer l'apoptose, la prolifération et de doser les cytokines. Les voies de signalisation ont été explorées par une technique d'antibody-array et par western blot. Les résultats confirment que les TLRs sont actifs et répondent à leurs ligands sur les cellules leucémiques. L'Imiquimod induit une apoptose accrue des cellules tumorales, surtout chez les patients stables et mutés, impliquant également la voie p38MAPK. L'ODN induit la prolifération des cellules tumorales et les protège de l'apoptose, surtout pour les patients avec une forme agressive et/ou non mutée. Ceci s'accompagne de l'activation de nombreuses protéines anti-apoptotiques et de la production d'IL-8 et d'IL-6. Ces résultats suggèrent que l'Imiquimod et l'ODN pourraient entrer dans une stratégie d'immunothérapie adjuvante pour les patients atteints de LLC / Chronic lymphoid leukemia (CLL), characterized by in vivo resistance to apoptosis and poor immunogenicity of leukemic cells is a hetereogeneous disease. Immunochemotherapy has allowed to progress greatly in its treatment, but the identification of new immunotherapy targets would be welcome. In this context, the presence of TLR-7 and TLR-9 on CLL cells is a promising prospect. The main objective of this work was therefore to precise the effects of in vitro engagement of TLR-7 and TLR-9 on tumor cells by their respective ligands Imiquimod R837 and ODN CpG M362. These effects were examined on CLL classified according to clinical evolution and /or according to their IgVH mutational status. Separated cells from 40 patients were cultured for three days with medium alone, acetate phorbolmyristate (PMA) or Imiquimod or ODN. Flow cytometry allowed to study the expression of TLRs and differentiation antigens on CLL cells' surface, to evaluate apoptosis, measure proliferation and assay cytokines production. Signaling pathways were further studied by antibody-array and western blot. Data obtained confirmed that TLRs are active and respond to their ligands on CLL B-cells. Imiquimod induces increased apoptosis, especially in patients with stable disease or mutated IgVH, with the additional involvement of the p38MAPK pathway. ODN induces cell proliferation and protects them from apoptosis, mostly for patients with an aggressive disease and/or unmutated IgVH. This is concomitant of the activation of anti-apoptotic proteins and of the production of IL-8 and IL-6. These results suggest that Imiquimod and ODN could enter in an adjuvant immunotherapy strategy in CLL
27

Efeito do Imiquimode na CicatrizaÃÃo de Queimadura em Ratos / Efeitos do imiquimode na cicatrizaÃÃo de queimaduras em ratos

Charles Jean Gomes de Mesquita 07 April 2008 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Queimaduras podem causar substancial morbidade e contraturas devido à hiperproliferaÃÃo fibroblÃstica. O imiquimode, imunomodulador utilizado em doenÃas virais e neoplasias cutÃneas, promove resposta imune inata e adaptativa, interagindo com Toll-Like Receptors, permitindo reconhecer antÃgenos e cÃlulas invasoras, ativando cÃlulas de Langerhans e citocinas endÃgenas capazes de suprimir a hiperproliferaÃÃo fibroblÃstica, mostrando-se Ãtil no tratamento de cicatrizes hipertrÃficas e quelÃides. Inexistiam trabalhos sobre o imiquimode em queimaduras cutÃneas. Avaliou-se os efeitos do imiquimode na cicatrizaÃÃo de queimaduras utilizando-se mÃtodos macroscÃpicos, microscÃpicos e computacionais. Produziram-se queimaduras dÃrmicas profundas de cada lado da linha mÃdia dorsal em 32 ratos Wistar utilizando um ferro-de-solda modificado aplicado a pele por 9s. Instituiram-se tratamentos 3X/semana a partir do segundo dia pÃs-queimadura (D2PQ). No lado direito (controle) utilizou-se soluÃÃo salina isotÃnica (SAL). à esquerda utilizou-se imiquimode (IMQ) tÃpico 5%. Oito animais foram eutanasiados nos D4, D7, D14 e D21PQ, obtendo-se fotografias digitais e amostras teciduais. Na anÃlise macroscÃpica utilizou-se escala visual analÃgica (EVA), escala de exame clÃnico (EEC) e planimetria digital. Para anÃlises microscÃpicas utilizaram-se amostras coradas pela hematoxilina-eosina (HE) ou picrosirius-red (PR). Nas amostras HE, sob microscopia Ãtica, quantificou-se o tipo e a intensidade da reaÃÃo inflamatÃria e a involuÃÃo temporal do dano tecidual pela atribuiÃÃo de escores. Amostras PR foram analisadas à microscopia de luz polarizada, quantificando-se a densidade do colÃgeno tipo I e tipo III e razÃo colÃgeno I: colÃgeno III (RazÃo I:III). NÃo houve mortes, infecÃÃo nem autocanibalismo. Os parÃmetros biomÃtricos nÃo evidenciaram efeitos deletÃrios sobre o estado nutricional. A EVA favoreceu discretamente o grupo SAL (P=0,0491). A EEC nÃo mostrou diferenÃas significativas. A planimetria digital evidenciou menor velocidade de reparaÃÃo nas feridas do grupo IMQ (P<0,05). A quantificaÃÃo da Ãrea de lesÃo mostrou involuÃÃo similar, exceto no D14PQ onde a Ãrea de necrose era maior no grupo IMQ (P<0,05). A anÃlise histolÃgica qualitativa mostrou um processo reparatÃrio mais lentificado no grupo IMQ em todos os tempos. No D7PQ, a intensidade da reaÃÃo inflamatÃria foi classificada como discreta em 50% das feridas do grupo SAL e intensa ou moderada em 75% do grupo IMQ (P<0,005). No D21PQ a inflamaÃÃo foi mais extensa no grupo IMQ (P<0,005). Observou-se que 50% das feridas do grupo SAL exibiam reaÃÃo inflamatÃria subaguda e 37,5% crÃnica, enquanto nenhuma ferida do grupo IMQ mostrava inflamaÃÃo crÃnica no D7PQ (P<0,005). No D21PQ a inflamaÃÃo no grupo IMQ era subaguda (68,75%) e no grupo SAL 56,25% era crÃnica (P<0,05). A morfometria do colÃgeno evidenciou aumento do colÃgeno tipo I e diminuiÃÃo do colÃgeno tipo III nos dois grupos. A razÃo colÃgeno I: colÃgeno III foi menor no grupo IMQ em D4 e D21PQ (P<0,05). O modelo reproduziu queimaduras dÃrmicas, preservando anexos essenciais à reepitelizaÃÃo. A picrossirius-polarizaÃÃo foi eficaz no reconhecimento do colÃgeno e os mÃtodos computacionais foram eficientes, identificando diferenÃas mÃnimas no processo lesÃo-reparaÃÃo. O imiquimode foi eficaz em promover o processo inflamatÃrio e retardar a maturaÃÃo, gerando menor quantidade de fibrose / Burns can result in substantial morbidity because of fibroblastic hyperproliferation and contracture. Imiquimod is a immunomodifier -TLR-7 agonist used in viral diseases and in neoplastic conditions like actinic keratosis, melanoma, and non-melanoma skin cancer. It acts by promoting endogenous cytokines known to suppress fibroblast proliferation. A new recent use is in treating keloids and hypertrophic scars to reduce scarring. No study of the effect of imiquimod on cutaneous burns has been performed. This study examined burn healing in the presence of topical imiquimod by evaluation of wound appearance, computer-aided image analysis, and histology in a rat model. Standardized partial-thickness burns were produced on the dorsum of thirty-two Wistar rats. Right-sided wounds received therapy with isotonic saline (sham). Left-sided wounds were treated with imiquimod cream at 5% (IMQ). This was repeated 3 times/week after injury. Euthanasia was performed at 4th, 7th, 14th and 21st Postburn days (PBD). Wounds were harvested for histological analysis. Evaluation of wound appearance was performed using clinical assessment scale (CAS) and a visual analogue scale (VAS). Scars area and perimeter were measured using digital planimetry to assess wound edge migration by Gilmanâs modified Equation. Inflammation type and intensity was graded by histological scale. Collagen type was identified by picrosirius-polarization and morphometric analysis was performed. VAS scores showed discretally improved appearance in the imiquimod-treated wounds versus the saline-treated control at PBD21 (P=0.0491). There was no difference in CAS scores. Wound edge migration was significantly slowest in imiquimod-treated wounds (p<0.05). Histological evidence of partial thickness dermal injury with sparing of dermal appendage epithelial cells was seen in all wounds. Histologic characteristics of gradually diminished injured area between groups were similar except in imiquimod-treated wounds at PBD14 (p<0.05). Inflamattory state was bigger in imiquimod-treated wounds at PBD7 and PBD21 (p<0.005). At PBD7 there was no chronic-type of inflammatory reaction in imiquimod-treated group, although in saline-treated group chronic plus sub-acute type was present in 87.5% (p<0.005). At PBD21 68.75% of imiquimod-treated group showed acute plus subacute inflammatory state, and saline-treated group displayed chronic-type in 56.25% of the wounds. The total amount of collagen increased in both groups throughout all time points. Morphometry showed an inversed ratio type I to type III collagen. Ratios of type I collagen to type III collagen was much lower in imiquimod-treated wounds at PBD4 and PBD21. Topical treatment with Imiquimod 5% cream for partial-thickness burn wounds 3 times/week courses do not improve clinical appearance and scarring during late healing. There is no difference in histology during the short-term healing process. Computer-aided image proccessing was efficient to evaluate burned-wound healing. Wound healing and fibrosis was impaired in imiquimod- treated wound group
28

Vliv klíštěcích cystatinů na TLR - indukovanou maturaci myeloidních dendritických buněk / The effect of tick cystatins on TLR - induced maturation of myeloid dendritic cells

NERADOVÁ, Hana January 2014 (has links)
Tick saliva contains a lot of molecules with antihemostatic and immunosupressive effects.The goal of this thesis is to test the effects of tick salivary cystatins from I.ricinus and I.scapularis on TLR - induced maturation of bone-marrow derived dendritic cells and production of chosen cytokines. Over all, the supressive effect of tick cystatins was observed in relation to TLR-induced maturation of DC. In addition, cystatins enhanced production of IL-10 and attenuated induction of IL-12 cytokines.
29

Phenotype and function of imiquimod-treated MUTZ-3 derived Langerhans cells in potential psoriatic 3D skin model

Schousboe, Emilie Allentoft January 2023 (has links)
Upon encounter of an antigen, epidermis-resident Langerhans cells (LCs) become activated and present the processed antigen to T cells of the draining lymph nodes, resulting in tolerogenic or inflammatory responses. In psoriasis plaques, skin homeostasis is disrupted and replaced by an inflammatory dermatitis. Topical application of the anti-viral compound, imiquimod, induces a psoriasiform inflammatory condition, partly driven by LC production of pro-inflammatory cytokines. Differentiation of the myeloid progenitor cell line, MUTZ-3, produces MUTZ-3 derived Langerhans cells (MUTZ-LCs) which can be used as an in vitro model of LCs. This project aimed to investigate the phenotype and function of imiquimod-treated MUTZ-LCs in monolayer cultures, co-culture with T cells and inserted into a 3D skin model. LC-related surface markers (HLA-DR, CD1a, CD207, CCR7) were upregulated in MUTZ-LCs after 7 days of differentiation with 40 ng/ml GM-CSF, 10 ng/ml TGF-β and 2.5 ng/ml TNF-α. Supernatants of imiquimod-treated monolayer cultures of MUTZ-LCs showed subtle concentrations of IL-6 and TNF-α, but not IL-23. mRNA expression showed no significant upregulation of IL-6, IL-23 or TNF-α after 24 h treatment with imiquimod. The presence of MUTZ-LCs in T cell co-cultures greatly increased the production of IL-2, but did not affect expression of CD25. After 16 h exposure to imiquimod, IL-6, IL-23 and TNF-α could not be detected in culture supernatants of a 3D model consisting of fibroblasts, keratinocytes and MUTZ-LCs. The model was devoid of fibroblasts after 19 days of culture, most likely compromising the immunocompetence, as LC migration in response to activation could not be detected. Further studies could refine and optimize the imiquimod-3D skin model, which has potential as a possible substitute for animal models in psoriasis research.
30

Elaboration de nanoparticules de poly (acide lactique) multifonctionnelles comme adjuvants potentiels de vaccination

Handke, Nadege 12 December 2011 (has links)
La vaccination est l’un des moyens les plus efficaces de la médecine moderne dans le combat contre les maladies infectieuses. L’amélioration de l’efficacité des vaccins requiert la mise au point d’adjuvants permettant d’accroître la qualité de la réponse immunitaire. À titre d’exemple, les nanoparticules (NP) de poly(acide lactique) (PLA) constituent un système efficace pour la délivrance d’antigènes. Afin de renforcer leur potentiel vaccinal, ce travail de recherche a eu pour objectif d’élaborer des NP de PLA décorées en surface par des molécules immunostimulantes, le D-mannose ou un peptide dérivé de l’interleukine-Beta, et au cœur, par l’imiquimod. Notre stratégie repose sur l’utilisation d’un tensioactif macromoléculaire composé d’un bloc de PLA et d’un bloc de poly(N-acryloxysuccinimide-co-N-vinylpyrrolidone) (P(NAS-co-NVP)), dont les fonctions ester de N-succinimidyle (NS) permettent le couplage de biomolécules. Ce copolymère a été synthétisé par combinaison de la polymérisation par ouverture de cycle et de la polymérisation radicalaire contrôlée par les nitroxydes (NMP). Après l’étude de la copolymérisation du NAS et de la NVP par NMP à partir d’une alcoxyamine modèle (MAMA-SG1), leur copolymérisation a été réalisée à partir de la macro-alcoxyamine PLA-SG1, conduisant au copolymère PLA-b-P(NAS-co-NVP) désiré. Des NP de PLA ont alors été préparées par nanoprécipitation et diafiltration en présence du copolymère, conduisant à des tailles respectives de 150 et 500 nm. Des études de potentiel zêta et de spectrométrie UV ont démontré la présence des esters de NS à la surface des NP (2.4 fonctions.nm-2), disponibles pour le couplage des biomolécules. Des micelles de copolymère ont été également préparées, après substitution des esters de NS par des sucres, et permettent une encapsulation efficace de l’imiquimod, contrairement aux NP de PLA. Ces systèmes constituent une plateforme flexible d’adjuvants potentiels comme alternative aux adjuvants non biodégradables actuellement utilisés. / Vaccination represents one of the most powerful tools of medicine for the fight against infectious diseases. The improvement of vaccine efficiency needs the development of adjuvants able to increase the quality of the immune response. Poly(lactic acid) (PLA) nanoparticles (NPs) represent an efficient system for antigen delivery. In order to improve their vaccine potential, the goal of this research work was to elaborate PLA NPs decorated at the surface with immunostimulatory molecules, D-mannose or peptide derived from interleukine-Beta, and into the core with imiquimod. Our strategy relies on the use of a macromolecular surfactant composed of a PLA block and a poly(N- acryloxysuccinimide-co-N-vinylpyrrolidone) (P(NAS-co-NVP)) block, whose N-succinimidyl (NS) activated esters allow the coupling of biomolecules. This diblock copolymer was synthesized by the combination of ring opening polymerization and nitroxide mediated polymerization (NMP). After the study of the copolymerization of NAS and NVP by NMP from the MAMA-SG1 model alkoxyamine, their copolymerization was performed from the macro-alkoxyamine PLA-SG1, leading to the desired copolymer PLA-b-P(NAS-co-NVP). PLA NPs were then prepared by nanoprecipitation and diafiltration, in the presence of the copolymer, leading to 150 nm and 500 nm sized particles, respectively. Studies of zeta potential and UV spectrometry demonstrated the presence of NS-activated esters at the NP surface (2.4 functions.nm-2), available for the coupling of biomolecules. Micelles from copolymer were also prepared, after substitution of esters with carbohydrates, and allowed an efficient encapsulation of imiquimod, contrary to PLA NPs. These systems represent a flexible platform of potential adjuvants as an alternative to non-biodegradable adjuvants currently used.

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