De nombreuses données expérimentales et cliniques ont montré l'importance des cellules Natural Killer (NK) dans l'immunosurveillance antitumorale. Les stratégies thérapeutiques basées sur les cellules NK pourraient donc être une alternative de choix dans le traitement de certains types de cancers. Nous avons focalisé notre étude sur deux types de cancer incurables malgré les récents progrès thérapeutiques : la leucémie lymphoïde chronique B (LLC-B) et le cancer de la prostate. Le but de notre étude est une meilleure compréhension des mécanismes mis en place par les cellules B leucémiques et les cellules tumorales prostatiques pour échapper à la réponse antitumorale des cellules NK. La connaissance de ces mécanismes d'échappement est un pré-requis indispensable à l'utilisation des cellules NK dans les thérapies antitumorales. Concernant la LLC-B, nos résultats suggèrent que les cellules NK de patients, fonctionnellement compétentes, ne peuvent pas initier une réaction immunitaire appropriée envers les cellules B leucémiques due au manque de reconnaissance de ces dernières. Concernant le cancer de la prostate, nos données préliminaires montrent que les cellules NK circulantes de patients sont également fonctionnellement compétentes, quelque soit le stade de la maladie, malgré la diminution significative de l'expression du récepteur NKp30. Ainsi, le degré d’immunogénicité des cellules B leucémiques et celui des cellules tumorales prostatiques devra être autant pris en compte que la fonctionnalité des cellules NK dans les stratégies visant à optimiser l'activité antitumorale de ces dernières. / Many experimental and clinical data have enlightened the importance of Natural Killer (NK) cells in tumor immunosurveillance. Therapeutic strategies based on NK cells could be an alternative in the treatment of certain cancers. We focused our study on two types of incurable cancers despite recent advances in treatment: B chronic lymphocytic leukemia (B-CLL) and prostate cancer. The aim of our study is a better understanding of the mechanisms set up by leukemic B cells and prostate cancer cells to escape from NK antitumor response. The knowledge of these escape mechanisms is an essential prerequisite to the use of NK cells in antitumor therapies. Regarding B-CLL, our results suggest that NK cells, although functionally competent, can not initiate an appropriate immune response against leukemic B cells due to a lack of recognition of the latter. Concerning the prostate cancer, our preliminary data show that circulating NK cells are functionally competent, whatever the stage of disease, despite the significant decrease in expression of the receptor NKp30. Thus, the degree of immunogenicity of leukemic B cells and of the prostate cancer cells must be taken into account as well as the functionality of NK cells in strategies aiming at improving NK antitumor activity.

L'infection chronique par le virus de l'hépatite B (VHB) touche 400 millions de personnes dans le monde et conduit à 1 million de décès par an des suites de complications hépatiques. Les traitements actuels permettent de freiner la progression de la maladie mais ne guérissent les patients que dans de très rares cas (3-5%). Le besoin médical pour de nouvelles thérapies est fort et les approches de type immunothérapie semblent aujourd'hui prometteuses dans cette pathologie où des corrélats immunitaires de résolution sont établis. Le but de cette thèse a été l'étude approfondie de candidats d'immunothérapie basés sur un vecteur adénovirus de sérotype 5 humain non réplicatif codant pour plusieurs antigènes du VHB. Des études in vitro et dans un modèle murin, ont montré la capacité : 1/ des antigènes du VHB codés par certains candidats a formé des VLP (microscopie électronique) 2/ des candidats à induire un recrutement de cellules immunitaires sur le site d'injection après administration par voie sous-cutanée. Des études in vivo utilisant un candidat prototype ont visé à caractériser les réponses immunitaires induites et à étudier l'impact de schémas d'immunisation atypiques, tels que ceux qui pourraient être utilisés en clinique. Elles ont montré la capacité du prototype, qu'il soit injecté une ou de multiples fois, à induire des réponses T CD8+ spécifiques du VHB, fortes, multispécifiques et maintenues dans le temps dans des modèles murins naïfs ou tolérants pour le VHB. Les administrations multiples n'ont pas conduit à une augmentation de la proportion de cellules T spécifiques du VHB exprimant des molécules d'inhibition, de type PD1 / Chronic infection with hepatitis B virus (HBV) affects 400 million people worldwide and leads to 1 million of deaths per year as a result of liver complications. Current treatments can slow the progression of the disease but cure patients in very rare cases (3-5%). The medical need for new therapies is obvious, strong and immunotherapy approaches appear promising in this disease, where immune correlates of resolution are established. The aim of this thesis was a comprehensive study of immunotherapeutic candidates, based on a non-replicating human adenovirus serotype 5 vector, encoding several antigens of HBV. Studies in vitro and in a mouse model, showed the ability of: 1 / HBV antigens encoded by some candidates to form VLPs (electron microscopy) 2 / candidates to induce recruitment of immune cells at the injection site after subcutaneous administration. In vivo studies using a prototype candidate aimed at characterizing the induced immune responses and to study the impact of atypical immunization schedules, which could be clinically used. They demonstrated the ability of the prototype, injected once or multiple times, to induce strong, multispecific and sustained over time HBV specific CD8 + T cells, in naive or tolerant to HBV mouse models. Multiple administrations do not increase the proportion of HBV specific T cells expressing inhibitory molecules, such as PD1

A prevalência de alergias vem aumentando no mundo todo, em especial a asma alérgica que é considerada uma síndrome inflamatória pulmonar, que em sua forma clássica está associada ao descontrole da atividade de células T helper (Th) 2. As terapias correntes são em sua maioria sintomáticas. Porém, a imunoterapia específica (SIT, do inglês Specific-Immunotherapy ) é potencialmente curativa. A SIT consiste na adminsitração do alérgeno específico repetidamente em doses crescentes com o objetivo de promover a dessensibilização do paciente. O presente trabalho, utilizando a ovoalbumina (OVA) como alérgeno em modelo de asma alérgica experimental, investigou protocolos profiláticos e terapêuticos de SIT. Durante a realização do protocolo profilático, os animais foram sensibilizados com OVA adsorvida em hidróxido de alumínio (Alum) associada com diferentes agonistas de receptores do tipo toll (TLR, do inglês toll-like receptors ). O agonista de TLR 9 (CpG) foi o mais eficiente em inibir a sensibilização alérgica quando comparado aos demais agonistas de TLR testados. Esta inibição do desenvolvimento da inflamação alérgica pulmonar por CpG foi dependente da molécula IL-10 e da sinalização via MyD88 nas células dendríticas. Além disso, sabendo que a SIT terapêutica, administrada pela via subcutânea é capaz de desencadear uma reação anafilática, encapsulamos a OVA em lipossoma catiônico 1,2-dioleoil-3-trimetilamônio-sulfato (DOTAP) com o intuito de aumentar a segurança da formulação e paralelamente potencializar o efeito do CpG. Os resultados verificaram que o encapsulamento da OVA diminuiu a reação anafilática cutânea e sistêmica induzida por este alérgeno. Verificamos também que a SIT com alérgeno/CpG encapsulados no DOTAP (OVA&#43CpG/DOTAP ou BT&#43CpG/DOTAP) promove uma significativa inibição da inflamação alérgica pulmonar e produção de IgE Total. Essa inibição da alergia pulmonar foi associada com o aumento da produção de IL-10, mas não de IFN-g no lavado bronco-alveolar (BAL). Notavelmente, o efeito terapêutico inibitório de OVA&#43CpG/DOTAP não foi verificado em animais deficientes para as moléculas de MyD88, IL-10 ou IFN-g. Verificamos que a SIT terapêutica também era dependente da sinalização via MyD88 nas células dendríticas. Além disso, ao utilizarmos animais reconstituídos com células de animais doadores alérgicos, verificamos que o efeito terapêutico da SIT não foi encontrado em animais reconstituídos com células de animais IFN-gKO, e que animais reconstituídos com células de animais IL-10KO apresentavam aumento de IL-10 no BAL. A transferência de células de medula óssea de animais C57BL/6 (WT), mas não de animais IFN-gKO, tratados com OVA&#43CpG/DOTAP foi capaz de reverter o quadro inflamatório alérgico de animais WT e induzir o aumento de IL-10 no BAL. Esses resultados contribuem para a elucidação dos mecânismos envolvidos na ação anti-inflamatória da SIT e potenciais utilizações do CpG e DOTAP em processos alérgicos. / The prevalence of allergies is increasing worldwide, especially allergic asthma that is considere a pulmonary inflammatory syndrome, which in its classic form is associated with the lack of control of T helper cell (Th) 2 activity. Current therapies are mostly symptomatic. However, specific immunotherapy (SIT) is potentially curative. SIT consists of administering the specific allergen repeatedly in increasing doses in order to promote patient desensitization. The present study, using ovalbumin (OVA) as an allergen in an experimental allergic asthma model, investigated prophylactic and therapeutic SIT protocols. During the prophylactic protocol, the animals were sensitized with OVA adsorbed on aluminum hydroxide (Alum) associated with different toll-like receptors (TLR) agonists. The TLR 9 agonist (CpG) was the most efficient in inhibiting allergic sensitization when compared to the other TLR agonists tested. This inhibition mediated by CpG of the development of the allergic lung inflammation was dependent on the IL-10 molecule and the MyD88 signaling in dendritic cells. In addition, knowing that the therapeutic SIT, administered by the subcutaneous route is capable of triggering an anaphylactic reaction, we encapsulated OVA in 1,2-dioleoyl-3-trimethylammonium sulphate (DOTAP), a cationic liposome, in order to increase the safety of the formulation and in parallel potentiate the effect of CpG. The results showed that OVA encapsulation reduced the cutaneous and systemic anaphylactic reaction induced by this allergen. We also verified that SIT with the allergen and CpG encapsulated in DOTAP (OVA&#43 CpG/DOTAP or BT&#43CpG/DOTAP) promotes a significant inhibition of lung allergic inflammation and Total IgE production. This inhibition of lung inflammation was associated with increased production of IL-10 but not of IFN-g in the bronchoalveolar lavage (BAL). Notably, the inhibitory therapeutic effect of OVA&#43CpG/DOTAP was abrogate in animals deficient in the MyD88 or IL-10 or IFN-g molecules. We found that therapeutic SIT was also dependent on MyD88 signaling on dendritic cells. In addition, when we used animals reconstituted with cells from allergic donor animals, we found that the therapeutic effect of SIT was not found in animals reconstituted with cells from IFN-gKO animals, and that animals reconstituted with IL-10KO animal cells had increased IL -10 in the BAL. The transfer of bone marrow cells from C57BL/6 (WT) animals but not from IFN-gKO animals treated with OVA&#43CpG/DOTAP was able to reverse the lung allergic inflammation of WT animals and induce the increase of IL-10 in the BAL. These results contribute to the elucidation of the mechanisms involved in the anti-inflammatory effect of the SIT and potential uses of CpG and DOTAP in allergic processes.

L’oncologie actuelle est encore confrontée à la résistance et à la progression rapide des cancers. Les mécanismes de résistance intrinsèque développés par les cellules tumorales peuvent compromettre l’efficacité des chimiothérapies et des immunothérapies. Il est maintenant admis que l’état de la réponse immunitaire de l’hôte détermine en partie l’issue thérapeutique des patients. L’objectif de notre équipe de recherche est donc de caractériser cette réponse et d’étudier l’impact des thérapies conventionnelles sur celle-ci dans le but d’identifier les mécanismes liés à un échappement futur de la tumeur. Dans ce contexte, nous avons montré qu’une chimiothérapie (5-FU, oxaliplatine, anti-VEGF (« Vascular Endothelium Growth Factor » : FOLFOX-bevacizumab) provoque chez certains patients une chute des gMDSC (cellules myéloïdes immunosuppressives granulocytaires) périphériques qui est associée à une meilleure réponse thérapeutique. Comme chez la souris, cet effet sur les gMDSC provoque néanmoins une élévation des Th17, une population pro-angiogénique, qui limite l’efficacité de la chimiothérapie. La suite de notre travail a eu pour objectif de tester l’effet « anti-Th17 » de l’activation de l’histone désacétylase SIRT1. SIRT1 est une enzyme capable de perturber l’acétylation de STAT3, un facteur essentiel à la différenciation des Th17. Nous avons montré que l’utilisation d’agonistes pharmacologiques de SIRT1 (resvératrol, SRT1720, metformine) inhibe la polarisation des Th17 par la désacétylation de STAT3 et que cet effet permet de limiter la croissance tumorale dans un modèle de cancer colique et de mélanome chez la souris (B16F10, CT26). Nous avons validé ce concept chez l’homme, ce qui suggère qu’il est possible de cibler les Th17 par cette stratégie en complément de la chimiothérapie. Le dernier volet de ce travail est consacré à la comparaison du profil immunologique périphérique de volontaires sains à celui d’une cohorte prospective de cancers bronchiques non à petites cellules. Cette étude nous a permis de mettre en lumière les altérations immunitaires induites par la tumeur et de lier ces altérations à la réponse au nivolumab (anti-PD-1). Un premier modèle prédictif de réponse a pu être généré grâce aux données d’un panel d’analyse des cellules myéloïdes. Ce modèle révèle une fois encore que les cellules gMDSC ont un rôle prédictif défavorable, alors que les populations présentatrices d’antigènes (cellules dendritiques et monocytes) exprimant PD-L1 ont un bon rôle prédictif. Les données présentées dans cette partie sont préliminaires et devront être confirmées avec la cohorte de validation qui est en cours d’inclusion. L’ensemble de ce travail a permis de montrer qu’il est essentiel de cibler spécifiquement les cellules myéloïdes immunosuppressives et les Th17 pour favoriser l’efficacité des chimiothérapies et de l’immunothérapie dans le cancer. / Actual oncology is still facing resistance and rapid progression of cancer. Intrinsic resistance mechanisms developed by tumor cells determine chemotherapy and immunotherapy efficacy. It is now recognized that the host immune response status is in part implicated in the therapeutic outcome of patients. The aim of our research team is to characterize this response and to study the impact of therapies in order to identify the mechanisms associated with future exhaust of the tumor. In this context, we have shown that chemotherapy (5-FU, oxaliplatin, anti-VEGF: FOLFOX-bevacizumab) in some patients causes a drop in devices gMDSC (granulocytic myeloid derived suppressive cells) that is associated with better therapeutic response. Nevertheless, as in mice, this effect on gMDSC causes an elevation of Th17, a pro-angiogenic population, which limits the effectiveness of chemotherapy. The result of our work was aimed to test the effect "anti-Th17" activating SIRT1 deacetylase histone. SIRT1 is an enzyme capable of disrupting the acetylation of STAT3, a key factor in the differentiation of Th17. We have shown that by using pharmacological agonists SIRT1 (resveratrol, SRT1720, metformin) inhibits Th17 polarization by deacetylation of STAT3 and that this effect can limit tumor growth in colorectal and melanoma murine models (B16F10, CT26). We validated this concept in humans, suggesting that it is possible to target Th17 cells by this strategy in addition to chemotherapy. The final component of this work is devoted to the comparison of peripheral immunological profile of healthy volunteers to a prospective cohort of non-small cell lung cancer. This study has allowed us to highlight the immune alterations induced by the tumor and to link these changes in response to nivolumab (anti-PD-1). A first response predictive model could be generated using data from a panel analysis of myeloid cells. This model proves once again that gMDSC have a negative predictive role, while antigen presenting (dendritic cells and monocytes) expressing PD-L1 has a good predictive role. Data presented in this section are preliminary and must be confirmed with the validation cohort that is currently included. All of this work has shown that it is essential to specifically target immunosuppressive myeloid cells and Th17 to promote the efficacy of chemotherapy and immunotherapy in cancer.

Avaliamos os mecanismos regulatórios desencadeados pela imunização materna na resposta alérgica da prole OVA. A imunização materna com OVA promoveu alterações como o aumento da expressão dos receptores FcgRIIb nos linfócitos B esplênicos dos neonatos aos 3 dias de idade (d.i.), o que se manteve até os 20 d.i. Com a imunização das proles no período neonatal a imunização materna inibiu a produção de anticorpos IgE anti-OVA. Além disso, foi observado na população de linfócitos B da prole o aumento da expressão dos receptores FcgRIIb e CD44. A transferência passiva de IgG de mães imunes no pós-natal mostrou uma inibição da produção de IgE, e no período pré-natal foi capaz de reduzir a expressão das moléculas CD40 e CD23 nos linfócitos B e a secreção de IL-10 em linfócitos T CD4 na prole no período neonatal. As evidências mostram que a imunização pré-concepcional com OVA induz mecanismos que regulam a resposta IgE da prole imunizada no período neonatal, o que foi parcialmente observado com a transferência passiva de anticorpos IgG durante o período pré e pós-natal. / To evaluate the regulatory mechanisms triggered by maternal immunization in the immune response of the offspring, the effect of preconceptional immunization with OVA was evaluated. Maternal immunization with OVA led to early alteration with increased expression of FcgRIIb in B lymphocytes from 3 days old pups. Offspring from immune mother showed diminished percentage of CD4 T cells IL-4+. The immunization of offspring during neonatal period showed that maternal immunization inhibits the production of anti-OVA IgE antibodies. The evaluation of CD4 T cell population revealed diminished IL-4+ cells. Passive IgG transfer from immune mother during neonatal period showed inhibition in the IgE synthesis, during pregnancy showed capacity to reduce the expression of CD40 molecules in B cells from neonatal pups. These evidences show that maternal OVA immunization down regulates the IgE response of offspring including phenotypic and functional alteration in B and CD4 T cells. These alterations were partially observed with IgG transfer during pregnancy or after birth.

As piodermites, superficiais ou profundas, representam uma das dermatopatias caninas mais comuns no cotidiano da clínica dermatológica de cães. Dentre as classificadas como superficiais, destacam-se a foliculite bacteriana e a piodermite esfoliativa ou superficial disseminada, que representam a grande maioria dos casos. Em alguns cães, as piodermites superficiais são idiopáticas, apresentam evolução crônica e caráter recidivante. A despeito de criteriosa investigação acerca de sua possível etiologia, por vezes, não se consegue evidenciar a causa para a instalação e recorrência do quadro mórbido. Tais animais apresentam frequentes recidivas, em variáveis períodos de tempo, após o término da terapia antibiótica. Para estes caninos, na bibliografia médico-veterinária há recomendação de emprego das controvertidas imunoterapia ou de antibioticoterapia sob a forma de pulsos. Portanto, objetivou-se na casuística do Serviço de Dermatologia do Hospital Veterinário da USP, determinar as principais espécies bacterianas envolvidas, a susceptibilidade destas frente a diferentes antimicrobianos, bactericidas ou bacteriostáticos, assim como, comparar a eficácia e a segurança de três distintos protocolos terapêuticos no manejo a longo prazo, de piodermites superficiais recidivantes idiopáticas. Utilizaram-se 23 animais, de quaisquer dos sexos, de distintas raças e faixas etárias. A amostragem foi aleatoriamente disposta em três grupos de experimentação (GI, GII, G III), respectivamente submetidos à imunoterapia com bacterina comercial (Estafilin®) e às pulsoterapias de \"finais de semana\" ou em \"semanas alternadas\", empregando-se cefalexina \"per os\". O principal patógeno, em 67,6 % da totalidade de isolamentos bacterianos, foi Staphylococcus intermedius. Evidenciou-se (32,4 %), ainda, as espécies S. hyicus, S. schleiferi subespécie coagulans, S. warneri e Micrococcus sp. Segundo os antibiogramas, os fármacos mais efetivos in vitro foram a amoxicilina associada ao clavulanato de potássio, a cefalexina e o ceftiofur. Verificou-se resposta plena em percentis de, respectivamente, 50,0 %, 33,3 % e 28,6 % nos Grupos II, III e I; destarte, ao se agrupar as respostas plena e moderada evidenciaram-se valores relativos de, respectivamente, 83,3 %, 50,0 % e 42,9 %. À luz da estatística (Teste do Qui Quadrado), não se observaram quaisquer diferenças estatisticamente significativas (p > 0,05) entre os percentuais de resposta aos três protocolos empregados. Todos eles mostraram-se seguros, sem acarretar efeitos adversos farmacodérmicos. / Superficial and deep pyodermas are common canine skin disorders in the small animal dermatology practice. Among the superficial form, the bacterial folliculitis and superficial spreading pyoderma represent the great majority of cases. Some dogs are affected by idiopathic, chronic and recurrent type of superficial pyoderma. Despite a rigorous search for possible reasons for its etiology, sometimes it is not possible to determine an underlying cause for the disease recurrence. At variable time periods, these dogs show frequent recurrent episodes, after the interruption of antibiotic therapy. For these patients, the veterinary medicine literature recommends the use of the controversial immune therapy or antibiotic pulse therapy. Thus, using the University of Sao Paulo / Dermatology Service\'s casuistry the present study aimed to determine the major bacterial species responsible for pyodermas, their susceptibility to several bactericidal and bacteriostatic antibiotics as well as compare the efficacy and safety of three different therapeutics protocols for the long term management of idiopathic recurrent superficial pyoderma. A total of 23 male and female, purebred dogs from different ages were randomly allocated in three distinct experimental groups (G I, G II and G III), respectively treated with bacterin immune therapy, \"weekend\" antibiotic pulse therapy and \"week on - week off\" antibiotic pulse therapy, receiving cephalexin PO. S. intermedius was identified from 67,6 % of the totality of bacterial isolates and the remaining 32,4 % was composed of S. hyicus, S. schleiferi subspecie coagulans, S. warneri and Micrococcus sp. According to the antimicrobial susceptibility results the more effective drugs were amoxicillin plus potassium clavulanate, cephalexin and ceftioufur. In percentage values a full response of 50,0 %, 33,3 % and 28,6 % was achieved in Groups I, II and III, respectively. On the other hand, when the comparison was made considering full and moderate together the values were 83,3 %, 50,0 % and 42,9 % for Groups I, II and III, respectively. Through a statistical analysis (Qui score test) no significant difference (p > 0,05) among the response to treatment percentage values was observed for the three groups. All treatments were secure and no drug eruption side effects were observed.

Objetivo: O objetivo desse estudo foi avaliar alterações na resposta clínica e imunológica ao camarão após a imunoterapia com Dermatophagoides pteronyssinus. Métodos: Selecionou-se 35 indivíduos alérgicos a Dermatophagoides pteronyssinus (Der p), os quais foram submetidos a testes cutâneos de leitura imediata para ácaros, baratas, camarão, tropomiosina recombinante, além de cão, gato e fungos. A detecção de IgE espcífica in vitro foi feita para o ácaro, camarão, barata americana e para suas tropomiosinas. Em todos, avaliou-se reatividade clínica ao camarão através de provocação oral. Dez pacientes foram alocados para o grupo controle, e 25 foram submetidos à imunoterapia alérgeno específica para o ácaro. Os testes cutâneos e a dosagem de IgE sérica específica foram repetidas após a indução da imunoterapia, e após 1 ano do início. A reatividade clínica ao camarão foi reavaliada no final do estudo pela provocação oral. Resultados: No grupo dos pacientes que foram submetidos à imunoterapia, observamos diminuição na reatividade nos testes cutâneos e dosagem de IgE específica para Der p, camarão e tropomiosina recombinante. Dos 10 pacientes com testes cutâneos positivos para camarão, 4 foram negativos na dosagem após um ano de imunoterapia (p= 0,04). Quanto à dosagem sérica de IgE para camarão, dos 9 positivos no início, 6 ficaram negativos (p= 0,014). Nenhum paciente submetido a imunoterapia desenvolveu nova sensibilização para camarão. Não houve alteração na reatividade clínica ao camarão após imunoterapia. Conclusão: A imunoterapia para Dermatophagoides pteronyssinus foi acompanhada de diminuição da reatividade imunológica para camarão e clinicamente não houve alteração da sensibilidade a camarão / Objective: The objective of this study was to determine changes in clinical and immunological response to shrimp after immunotherapy with Dermatophagoides pteronyssinus. Methods: We studied 35 allergic subjects to Dermatophagoides pteronyssinus (Der p), submitted to skin tests to mites, cockroach, shrimp, recombinant tropomyosin, and dog, cat and fungi. The detection of serum specific IgE was performed to mite, shrimp, and tropomyosin from American cockroach. In all patients, the clinical reactivity to shrimp was assessed through oral challenge. Ten patients were allocated to the control group, and 25 were submitted to immunotherapy for mite. Skin tests and determination of serum specific IgE were repeated after the induction of immunotherapy (3-4 months) and 1 year after of beginning of the treatment. The clinical reactivity to shrimp was assessed again at the end of the study by oral challenge. Results: In the group of patients who were undergoing immunotherapy, we observed decreased reactivity in the skin tests and specific IgE levels to Der p, shrimp and recombinant tropomyosin. Among the 10 patients with positive skin tests to shrimp, 4 were negative when assessed after one year of immunotherapy (p = 0.04). About serum specific IgE to shrimp, from the 9 positive reactors in the beginning of treatment, 6 became negative (p= 0.014). There was no change in clinical reactivity to shrimp after immunotherapy. Conclusion: The immunotherapy for Dermatophagoides pteronyssinus was accompanied by decreased immune reactivity to shrimp and clinically there was no change in sensitivity to shrimp

A hipersensibilidade a veneno de Hymenoptera representa importante problema do ponto de vista de saúde da população, uma vez que pacientes alérgicos aos componentes do veneno podem desenvolver reações graves, às vezes fatais. A única profilaxia efetiva em pacientes sensibilizados é a imunoterapia veneno específica. Objetivos: avaliar as evidências científicas a respeito dos efeitos da imunoterapia específica utilizada na profilaxia secundária das reações graves em pacientes sensibilizados a veneno de Hymenoptera, por meio da realização de uma revisão sistemática. Métodos: a estratégia de busca seguiu as recomendações do Grupo de Pele da Colaboração Cochrane. A pesquisa foi realizada nas seguintes bases de dados: MEDLINE, the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library), EMBASE, LILACS, SciSEARCH e nas referências de artigos mais relevantes. Todos os ensaios clínicos controlados e randomizados envolvendo imunoterapia com veneno de Hymenoptera versus imunoterapia com placebo ou apenas seguimento dos pacientes foram avaliados. Dois revisores de forma independente (ASW e LAMF) avaliaram a elegibilidade e a qualidade metodológica de cada ensaio clínico e extraíram os dados. O risco de reações sistêmicas, conseqüentes a ferroada acidental ou a teste de provocação com o inseto responsável, após a imunoterapia específica, foi avaliado por meio do cálculo do odds ratio e do respectivo intervalo de confiança de 95%. Resultados: 2267 resumos foram identificados. A maioria dos artigos foi excluída pelas seguintes razões: os estudos não eram controlados e randomizados ou não satisfaziam alguns critérios de inclusão. Apenas quatro estudos foram analisados. A idade dos pacientes variou entre dois e 65 anos. Apenas um estudo comparou imunoterapia com veneno de formiga contra placebo (Brown et al.) e três estudos (Hunt et al., Schubert et al. e Valentine et al.) comparam imunoterapia com venenos de abelha e vespa contra placebo ou seguimento de pacientes. Em cada estudo, o odds ratio para reações sistêmicas foi: Hunt et al.- Grupo I (veneno) x III (placebo): 0,10 (0,01 <OR < 0,68) Schubert et al.: 0,35 (0,05<OR<2,56); Valentine et al.: 0,16 (0,02 < OR < 1,21) e Brown et al.: 0,04 (0,01<OR<0,28). Após o teste de heterogeneidade, apenas dois estudos (Schuberth 1983 e Valentine 1990) se mostraram homogêneos o suficiente e assim puderam ser incluídos na meta-análise (p = 0,623). Ao combinar os dois estudos, o odds ratio passou a ser significativo: 0.29 (0.10 a 0.87). Entretanto, ao analisar a gravidade das reações ocorridas após a imunoterapia, observou-se que os benefícios podem não ser tão relevantes, pois as reações foram, na grande maioria, ou mais leves ou semelhantes à reação original. Conclusões: A imunoterapia específica deve ser recomendada para adultos que apresentaram reações sistêmicas e para crianças com reações moderadas a graves, porém não é necessária em crianças que apresentaram apenas reações cutâneas após ferroada de abelha ou vespa, principalmente se a exposição for esporádica. / Background: Hymenoptera venom hypersensitivity is a significant public health problem. For patients who are allergic to components of the venom, reactions can be severe and sometimes fatal. The only effective treatment in the management of those patients is the specific venom immunotherapy. Objective: to assess the effects of the specific venom immunotherapy for Hymenoptera venom hypersensitivity through a systematic review. Methods: the standard search strategy of the Cochrane Skin Group was used for searches of electronic and other databases. These included MEDLINE, the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library), EMBASE, LILACS, SciSEARCH and the references of relevant articles. All randomized controlled trials involving Hymenoptera venom immunotherapy versus immunotherapy with placebo or only follow-up of the patients were included. Two independent reviewers (ASW and LAMF) assessed the eligibility, and the methodological quality of each trial, and extracted the data. Post immunotherapy risk of systemic reactions after either challenge or accidental stings was calculated through the odds ratio and respective 95 percent confidence interval. Main results: 2,267 abstracts, identified through electronic sources, were assessed. Most articles were excluded for the following reasons: the studies did not satisfy all the inclusion criteria or they were not randomized controlled trials. Four studies were included on this review. The age of the participants varied between two and 65 years. Only one study compared ant venom immunotherapy with placebo (Brown et al.) and three studies (Hunt et al., Schubert et al. and Valentine et al.) compared bees and wasps immunotherapy with placebo or simply patient follow-up. In each study, the odds ratio to a systemic reaction was: Hunt et al.- Group I (venom) x III(placebo): 0,10 (0,01 < OR < 0,68) Schubert et al.: 0,35 (0,05 < OR < 2,56); Valentine et al.: 0,16 (0,02 < OR < 1,21) and Brown et al.: 0,04 (0,01 < OR < 0,28). After the heterogeneity test (p = 0,623), only two studies (Schuberth 1983 and Valentine 1990) were homogeneous enough as to be included in a meta-analysis. The summary odds ratio was 0.29 (IC 95%: 0.10 - 0.87). However, when the severity of the reaction occurring after the sting challenge or accidental sting was taken into account, the benefits were not so relevant because the reactions were, for the most, milder than the original one. Conclusions: The specific-venom immunotherapy must be recommended for adults with systemic reactions and for children with moderate to severe reactions, but there is no need to prescribe it for children who present only skin reactions after insects sting, particularly if the exposure is sporadic.

As células dendríticas (DCs) são as principais células apresentadoras de antígenos (APCs). Foi proposto que as DCs selecionam os Ags que serão apresentados em MHC-II baseado na presença de ligantes para TLR na partícula fagocitada. Contudo, esse fenômeno não foi estudado em classe I. Assim, o objetivo deste estudo foi investigar se o acoplamento de Ags particulados a um agonista de TLR melhoraria a apresentação cruzada (AC) dos mesmos por DCs humanas tratadas com as moléculas acopladas. Nós vimos que a presença de um ligante de TLR no material fagocitado não contribuiu nem para a maturação do fagossomo, nem para a via endossômica de AC. A AC não envolve acidificação endossômica e depende de moléculas de MHC recém-sintetizadas do retículo endoplasmático. Nossos dados confirmam também a importância do estado de maturação das DCs para a indução de proliferação de LT CD8+, embora este não tenha sido associado com o nível de apresentação do complexo MHC-I/peptídeo, ou com as moléculas normalmente utilizadas para indicar a maturação das DCs. / Dendritic cells (DCs) are the main antigen presenting cells (APCs). It was proposed that DCs select the Ags that will be presented at their surfaces on class II based on the presence of a TLR-ligand on the cargo. However, the relevance of the coupling of the Ag to a TLR-ligand on class I was not yet addressed. Thus, the goal of this study was to investigate whether the coupling of particulate Ags to a TLR-agonist improve the cross-presentation (CP). We saw that the CP does not involve endosomal acidification and it relies on newly synthesized MHC-I molecules from the endoplasmic reticulum. Also, the presence of a TLR-ligand on the cargo neither contributed to the phagosome maturation nor to the endosomic route of CP. Furthermore, the maturation status of DCs was crucial for the induction of CD8+ T cells proliferation. Although the coupling of the Ag to the adjuvant has neither changed the expression of the markers related to maturation nor the presentation of the complex MHC-I/peptide at the DC surface, it affected its capacity of stimulating CD8+ T cells.

Células dendríticas (DCs) são células apresentadoras de antígenos usadas em estratégias imunoterapêuticas, como as que utilizam híbridos de DCs e células tumorais. Este projeto avaliou a possibilidade de utilizar, como parceiro de fusão das DCs, células de linhagem tumoral previamente transfectadas com mRNA amplificado de células tumorais contra as quais se pretende induzir resposta. Os híbridos foram capazes de induzir uma resposta antígeno-específica e foi possível enriquecer uma célula com antígenos de outra, uma vez que células transfectadas passaram a apresentar mRNAs da célula doadora, e expressar GFP quando a célula doadora era positiva para GFP. Foi possível amplificar integralmente o mRNA para GFP e amplificar os mRNAs de uma célula, gerando um material contendo mRNAs do preparado inicial mas incapaz de aumentar a expressão das moléculas avaliadas nas células transfectadas, mostrando que o protocolo ainda precisa ser aperfeiçoado. Em conjunto, os resultados mostraram que a estratégia de imunoterapia aqui explorada é promissora e merece maior investigação. / Dendritic cells (DCs) are antigen presenting cells widely used in immunotherapy strategies, as the ones that utilize dendritic cell tumor cell hybrids. The present project evaluated the possibility of using cells from tumor cell lines, which were previously transfected with mRNA amplified from tumor cells against which a response is aimed, to fuse with DCs. The hybrids were able to induce a specific immune response. Also, it was possible to enriched one cell with antigens from another one, since transfected cells increased the amount of mRNAs from the donator cell, and expressed GFP when the donator cells expressed this protein. It was possible to successfully amplify the GFP specific mRNA. The mRNAs amplified from RNA of different cell lines contained mRNAs that were present in the total extracted RNA, but were not able to increase the expression of the molecules we attempted to detect in the transfected cells, showing that the protocol still need to be improved. Together, these results show that this new strategy is promising and deserves further investigation.