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<p>Insects encounter many microorganisms in nature and to survive they have developed counter measures against the invading pathogens. In <i>Drosophila melanogaster</i> research on insect immunity has mainly been focused on infections by bacteria and fungi. We have explored the immune response against natural infections of the parasite <i>Octosporea muscaedomesticae</i> and the <i>Drosophila</i> C virus as compared to natural infections of bacteria and fungi. By using Affymetrix <i>Drosophila</i> GeneChips, we were able to obtain 48 genes uniquely induced after parasitic infection. It was also clearly shown that natural infections led to different results than when injecting the pathogens. </p><p>In order to search for the ultimate role of the lepidopteran protein hemolin, we used RNA interference (RNAi). We could show that injection of double stranded RNA (dsRNA) of <i>Hemolin</i> in pupae of <i>Hyalophora cecropia</i> led to embryonic malformation and lethality and that there was a sex specific difference. We continued the RNAi investigation of hemolin in another lepidopteran species, <i>Antheraea pernyi</i>, and discovered that hemolin was induced by dsRNA<i> per se</i>. A similar induction of hemolin was seen after infection with baculovirus and we therefore performed <i>in vivo</i> experiments on baculovirus infected pupae. We could show that a low dose of ds<i>Hemolin</i> prolonged the period before the <i>A. pernyi</i> pupae showed any symptoms of infection, while a high dose led to a more rapid onset of symptoms. By performing <i>in silico</i> analysis of the hemolin sequence from <i>A. pernyi</i> in comparison with other<i> Hemolin</i> sequences, it was possible to select a number of sites that either by being strongly conserved or variable could be important targets for future studies of hemolin function.</p>

Insects encounter many microorganisms in nature and to survive they have developed counter measures against the invading pathogens. In Drosophila melanogaster research on insect immunity has mainly been focused on infections by bacteria and fungi. We have explored the immune response against natural infections of the parasite Octosporea muscaedomesticae and the Drosophila C virus as compared to natural infections of bacteria and fungi. By using Affymetrix Drosophila GeneChips, we were able to obtain 48 genes uniquely induced after parasitic infection. It was also clearly shown that natural infections led to different results than when injecting the pathogens. In order to search for the ultimate role of the lepidopteran protein hemolin, we used RNA interference (RNAi). We could show that injection of double stranded RNA (dsRNA) of Hemolin in pupae of Hyalophora cecropia led to embryonic malformation and lethality and that there was a sex specific difference. We continued the RNAi investigation of hemolin in another lepidopteran species, Antheraea pernyi, and discovered that hemolin was induced by dsRNA per se. A similar induction of hemolin was seen after infection with baculovirus and we therefore performed in vivo experiments on baculovirus infected pupae. We could show that a low dose of dsHemolin prolonged the period before the A. pernyi pupae showed any symptoms of infection, while a high dose led to a more rapid onset of symptoms. By performing in silico analysis of the hemolin sequence from A. pernyi in comparison with other Hemolin sequences, it was possible to select a number of sites that either by being strongly conserved or variable could be important targets for future studies of hemolin function.

Orientador: Giovanni Faria Silva / Resumo: Introdução: O Vírus da Hepatite C está associado a manifestações extra-hepáticas, dentre elas a resistência à insulina (RI). Estudos baseados em Interferon (IFN) e Ribavirina (RBV) mostraram uma melhora da RI e da regressão de fibrose associada à Resposta Virológica Sustentada (RVS), mesmo em pacientes cirróticos.As evidências são incertas se isso ocorre com os Antivirais de Ação Direta (AADs). Objetivos: Avaliar a influência da RVS em cirróticos infectados pelo vírus da hepatite C (VHC) tratados com os AADs na RI, nos Lipídes Séricos, nos marcadores indiretos de atividade inflamatória, nos marcadores indiretos de fibrose hepática e nos escores de avaliação de função hepática. Metodologia: Estudo prospectivo longitudinal realizado no Ambulatório de Hepatites Virais da disciplina de Gastroenterologia do Hospital das Clínicas da Faculdade de Medicina de Botucatu em dois períodos: no início do tratamento (t-base) e na décima segunda semana após o fim do tratamento (t-RVS). Critérios de Inclusão: infecção pelo VHC (RNA-VHC positivo), idade ≥ 18 anos, conclusão da terapia com AADs, presença de cirrose hepática e amostras coletadas no t-base e t-RVS. Critérios de Exclusão: presença de coinfecção VHB/HIV, Carcinoma Hepatocelular no início do estudo ou no t-RVS, pacientes transplantados (fígado/rim). Para confirmação da cirrose utilizou-se a elastografia hepática ou biópsia (METAVIR), como também a clínica ou exames de imagem. Para avaliação indireta da fibrose hepática, utilizou-se ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Introduction: Hepatitis C virus is associated with extrahepatic manifestations, including insulin resistance (IR). Studies based on Interferon (IFN) and Ribavirin (RBV) have shown an improvement in IR and fibrosis regression associated with Sustained Virological Response (SVR), even in cirrhotic patients. This evidence is uncertain if this occurs with Direct Action Antivirals (DAAs). Objective: To evaluate the influence of SVR on hepatitis C virus (HCV) infected cirrhotic patients treated with DAAs in IR, Serum Lipids, indirect markers of inflammatory activity, indirect markers of hepatic fibrosis and evaluation scores of hepatic function. Methods: Prospective longitudinal study conducted at the Viral Hepatitis Outpatient Clinic of the Gastroenterology Department of the Clinical Hospital of Botucatu Medical School in two periods: at the beginning of treatment (t-base) and at the twelfth week after the end of treatment (t-SVR). Inclusion Criteria: HCV infection (age-positive HCV RNA), age ≥ 18 years, completion of DAAs therapy, presence of liver cirrhosis and samples collected at t-base and t-SVR. Exclusion Criteria: presence of HBV / HIV coinfection, Hepatocellular Carcinoma at baseline or in t-SVR, transplanted patients (liver / kidney). To confirm cirrhosis, hepatic elastography or biopsy (METAVIR) was performed, as were clinical or imaging tests. The following formulas were used for the indirect evaluation of hepatic fibrosis: APRI = AST (UI / L) / AST (UI / L) Normal Limi... (Complete abstract click electronic access below) / Mestre

A型インフルエンザウイルス（IAV）は毎年流行を繰り返すインフルエンザの主要な原因ウイルスである。本研究ではIAVを構成するタンパク質の1種、ヘマグルチニン（HA）を標的とする抗IAV薬の創製し、その効果を細胞・個体レベルで検討した。また、抗IAV薬の作用機序の解析を通じて、IAV感染を制御する液胞状オルガネラを見出しており、本論文では本オルガネラの生化学的・形態的性状についても詳細に解析している。 / 博士(理学) / Doctor of Philosophy in Science / 同志社大学 / Doshisha University

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Le maintien de l'intégrité génomique est crucial pour la préservation du potentiel des cellules souches hématopoïétiques (CSH). Les lésions de l'ADN dans les CSH sont associées à une capacité réduite à reconstituer l'hématopoïèse, à altérer le potentiel de différentiation et à accroître le risque de développer des tumeurs myéloïdes. Les éléments rétrotransposables (ER), se propageant dans le génome à travers un ARN intermédiaire, ont été associés à la perte d'auto-renouvellement, au vieillissement et aux dommages à l'ADN. Cependant, leur rôle dans les CSH n'avait pas été abordé. Dans cette étude, nous avons constaté que les CSH expriment des niveaux élevés d'ARNm de plusieurs ER comprenant des rétrovirus endogènes (ERV) et des L1 (LINE-1: Long Interspersed Nuclear Elements 1). Leur expression augmente avec l'irradiation. En utilisant des souris transgéniques L1-EGFP, on a montré que la rétrotransposition de L1 se produit dans les CSH in vivo. En outre, les inhibiteurs de la transcriptase inverse Efavirenz et ddC sauve à la fois les CSH des dommages persistants à l'ADN induit par l’irradiation et de la perte de prolifération in vitro. Ceci démontre que la rétrotransposition endogène joue un rôle important dans l'instabilité génomique de CSH induite par l’irradiation et dans leur perte de fonction. Nous avons précédemment montré que la thrombopoïétine (TPO), un facteur d'auto-renouvellement critique pour le CSH, limite les lésions de l'ADN induites par l’irradiation en améliorant la réparation de l'ADN. Nous avons découvert que le traitement par TPO empêche également l'expression et la mobilisation d’ER induite par l’irradiation. Nous avons aussi constaté que l’expression et la retrotransposition de L1 augmente dans les CSH provenant de souirs Mpl-/- et L1-EGFPxMpl-/-. Cela montre que la signalisation TPO in vivo est nécessaire pour restreindre l’expression et la retrotransposition d’ER dans les CSH au niveau basal et dans des conditions de stress. L'analyse transcriptomique a révélé que la TPO induit une réponse d'expression génique antivirale d'interféron (IFN) de type I dans les CSH. En utilisant des souris déficientes en STAT1/STAT2, nous démontrons que cette réponse est dépendante à la fois de STAT1 et de STAT2 et est requise pour l'inhibition de l'expression d’ER. En conclusion, cette étude montre que les ER représentent une importante source d’instabilité génomique dans les CSH. Les CSH sont capables de monter une réponse antivirale en réponse à la TPO comme un nouveau mécanisme pour limiter les dommages à l'ADN. Bien que la sécrétion constitutive d'IFN-I se produise chez des souris saines, les IFN sont produits abondamment principalement pendant les infections. Ainsi, la réponse d'expression de gène d'IFN induite par la TPO peut représenter un signal constitutif important et CSH-dédié; permettant à ces cellules de résister aux lésions de l'ADN induites par ER, tout en préservant leur capacité d'auto-renouvellement. / Maintenance of genomic integrity is crucial for the preservation of hematopoietic stem cell (HSC) potential. DNA damage in HSCs is associated with reduced ability to reconstitute hematopoiesis, altered lineage potential and accrued risk of developing myeloid malignancies. Retrotransposable elements (RE), spreading in the genome through an RNA intermediate, have been associated with loss of self-renewal, aging and DNA damage. However, their role in HSCs has not been addressed. In this study, we found that HSCs express high mRNA levels of several REs, including evolutionary recent long interspersed element-1 (L1) and endogenous retroviruses (ERV). Their expression further increases upon total body irradiation (TBI). Using L1EGFP transgenic reporter mice, we show that productive L1 retransposition occurs in HSCs in vivo. Furthermore, the reverse transcriptase inhibitors Efavirenz and ddC rescue TBI-induced both persistent DNA damage and HSC loss of proliferation in vitro. This demonstrates that endogenous retrotransposition plays an important role in TBI-induced HSC genomic instability and their loss of function. We have previously shown that thrombopoietin (TPO), a critical HSC self-renewal factor limits TBI-induced HSC DNA damage by improving DNA repair. We found that TPO treatment also prevents TBI-induced RE expression and mobilization. In addition, L1 expression and retrotransposition are increased in Mpl-/- and L1-EGFPxMpl-/- HSCs, showing that TPO signaling in vivo is required to restrain RE in HSCs, under both steady state and stress conditions. Transcriptomic analysis revealed that TPO induces an anti-viral, interferon (IFN) type-I like, gene expression response in HSCs. Using STAT1/STAT2-deficient mice, we demonstrate that this response is dependent on both STAT1 and STAT2 and is required for TPO-mediated RE expression inhibition in HSCs. Overall, this study shows that REs represent an important HSC intrinsic source of genomic instability and uncovers the ability of HSCs to mount an anti-viral innate immune state in response to TPO as a novel mechanism to minimize DNA damage. Although constitutive IFN-I secretion occurs in healthy mice, IFNs are produced abundantly mainly during infections. Thus, TPO-induced IFN gene expression response may represent an important constitutive, and HSC-dedicated, signal allowing HSCs to resist RE-induced DNA damage while preserving their self-renewal ability.

Made available in DSpace on 2016-03-22T17:27:14Z (GMT). No. of bitstreams: 1 Elza Bueno.pdf: 2003941 bytes, checksum: 176576d54fbdbc371386c7215923debb (MD5) Previous issue date: 2013-12-02 / Depressive symptoms have been frequently observed in association with immune activation. To prospectively evaluate, depressive symptoms and risk factors for major depression in patients with hepatitis C virus (HCV) treated with antiviral combined therapy. This study is a convenience cohort that evaluated 50 patients with HCV by the structured diagnostic interview - Mini International Neuropsychiatric Interview (MINI) to screen for depressive symptoms before antiviral combined therapy, and in the follow-up visits (4 and 12th week). Laboratorial analysis were performed during the follow-up. The study was approved by the University s Ethics Committee (151.642). We evaluated 50 patients, in which prevalence of genotype 1 was 42%. Pegylated interferon alpha (IFN-&#945;) and ribavirin was the most prevalent treatment used for HCV (86%). During the follow-up of patients, treatment for HCV increases the risk of depression in the 4th week (43.5.9%), but not at 12th week (30.7%) treatment compared with the baseline (25.6%) (p=0.04). We found differences between the prevalences of depression and genotypes of the virus in regard to time of the follow-up with higher odds ratio in the 4th week (OR=2.2) compared to baseline and 12th week (OR=1.8) using pairwise comparisons with Bonferroni adjustment (p=0.03). Also, patients with genotype 2 and 3 had significantly lower odds of presenting depression compared genotype 1 (p&#8804;0.05). However, the average score on the BDI-II did not differ in the follow-up.This study provide evidence of an association between HCV genotype and major depression. During the follow-up, depressive symptoms increase in 4th week, corresponding to conditions of immune activation. Major depression in HCV patients influence their health-related quality of life and their adherence to antiviral treatment 8 being important screening programmes, for early recognition and treatment of interferon-induced depression / Introdução:Os sintomas depressivos têm sido freqüentemente observados em associação com ativação imune .Objetivos: Avaliar prospectivamente , sintomas depressivos e fatores de risco para depressão maior em pacientes com o vírus da hepatite C (HCV ) tratados com terapia combinada antiviral . Metodologia: Este estudo é uma coorte de conveniência , que avaliou 50 pacientes com HCV por entrevista diagnóstica estruturada - Mini International Neuropsychiatric Interview ( MINI ) - para triagem de sintomas depressivos antes da terapia antiviral combinada , e nas visitas de acompanhamento (4 e 12 semanas ) . A análise laboratorial foi realizada durante o follow-up. O estudo foi aprovado pelo Comitê de Ética da Universidade (151,642). Resultados: Foram avaliados 50 pacientes, nos quais a prevalência do genótipo 1 foi de 42% . Interferon peguilado alfa (IFN - &#945;) e ribavirina era o tratamento mais prevalente utilizado para HCV ( 86 % ) . Durante o seguimento de pacientes, o tratamento para HCV aumenta o risco de depressão na 4 ª semana ( 43.5 %) , mas não a 12 ª semana (30,7%) em comparação com o tratamento inicial ( 25,6% ) (p = 0,04) . Foram encontradas diferenças entre as prevalências de depressão e genótipos do vírus em relação ao tempo de seguimento com maior razão de odds na 4 ª semana (OR = 2,2 ) em relação à linha de base e 12 ª semana (OR = 1,8 ), utilizando comparações pareadas com ajuste de Bonferroni (p = 0,03). Além disso, os pacientes com genótipo 2 e 3 tiveram chances significativamente menores de apresentar depressão, em comparação genótipo 1 (p &#8804; 0,05). No entanto, a pontuação média no BDI- II não foi diferente no estudo follow- up. Conclusão: Este estudo fornece evidências de uma associação entre o genótipo HCV e depressão maior. Durante o seguimento, os sintomas depressivos aumentam na 4 ª semana, o que corresponde a condições de ativação imune . A depressão maior em pacientes HCV influencia a qualidade de vida e sua adesão ao tratamento antiviral, sendo importantes programas de rastreio, para a identificação precoce e tratamento da depressão induzida por interferon.

Le risque de LH est augmenté en cas de déficit immunitaire acquis ou inné. Les déficits immunitaires innés associés à un risque accru de LH, sont les DICV (Déficit Immunitaire Commun Variable), XLP (Syndrome lymphoprolifératif lié au chromosome X) et ALPS (Syndrome lymphoprolifératif Autoimmun). L’objectif de notre travail était d’évaluer la prévalence de ces déficits immunitaires chez des enfants atteints de LH. Nous avons reçu, 395 prélèvements de patients atteints de LH au diagnostic. L’âge médian de la population étudiée est de 13 ans, allant de 3 à 18 ans. Le sex-ratio M/F est de 1.1. Il augmente à 3 au dessous de l’âge de 10 ans. Parmi les biopsies (n=84) qui ont été relues, 87% sont de type scléro-nodulaires (SN), 7% à cellularité mixte (CM) et 6% non spécifié. L’EBV est détecté in situ dans 23% des cas de LH. Les patients atteints de LH-EBV+ sont significativement plus jeunes que ceux atteints de LH-EBV- (p=3.10-4). Ce sont plus fréquemment des garçons que des filles (63% ; M/F : 1,7) et fréquemment de sous-type CM (40%). Enfin, ils ont une charge virale EBV significativement plus élevée (p=3.10-3) que les enfants qui ont un LH-EBV-.Parmi les 83 premiers enfants analysés, un immunophénotypage approfondi a montré une diminution de la population lymphocytaire par rapport aux témoins et une lymphopénie B fréquente (31 patients sur 83 soit 37% des patients). La lymphopénie B était corrélée aux facteurs pronostiques connus du LH. Dans un cas parmi les 31, une baisse des immunoglobulines a été mise en évidence ce qui est évocateur de DICV. Nous avons montré que dans les autres cas, les lymphopénies se corrigeaient à distance de la maladie. La recherche de profil cytokinique associé à ces lymphopénies (TGF, BAFF, IL-7) n’a pas permis de mettre en évidence de mécanisme physiopathologique simple pour expliquer ces lymphopénies. Nous émettons l’hypothèse qu’elles sont liées à l’exposition au contact des cellules tumorales à des signaux favorisant l’apopotose.En ce qui concerne la recherche d’autres déficits immunitaires innés, aucun cas évocateur de XLP n’a été mis en évidence sur la base de la quantification des lymphocytes NKT. Cinq cas parmi les 83 (6%) avaient une expansion de lymphocytes T DN (Lymphocytes TCRαβ CD4-CD8-) dans le sang périphérique. Des dosages de Fas ligand et d’IL-10 plasmatiques ont permis d’exclure un ALPS. Au total, nous n’avons pas pu affirmer de défaut qualitatif des sous-populations lymphocytaires évoquant les déficits immunitaires de type XLP et ALPS. Seule une lymphopénie B avec baisse des IgG est évocatrice de DICV. Nous avons étendu l’analyse à l’ensemble des patients (395patients) avec un contrôle à distance du diagnostic pour ceux qui étaient anormaux. Nous avons identifié 4 patients potentiellement atteints de DICV, 1,5%. Parallèlement, nous avons recherché un déficit de la réponse T anti-EBV par cytomètrie de flux et l’Elispot. L’étude de la réponse T anti-EBV par la cytométrie de flux, a montré une tendance vers une baisse de la production d’IL-2 par les CD4 et les CD8 de patients avec une charge virale EBV élevée en réponse à une stimulation par des peptides EBV en présence de lignées autologues. L’étude de la réponse T anti EBV par la technique d’ELISPOT sur 9 patients n’a pas montré globalement de déficit du contrôle de l’EBV sauf pour une jeune patiente de 10 ans ayant une charge virale EBV très élevée sans réponse T anti-EBV efficace. Les résultats que nous avons obtenus restent à approfondir, ce qui permettra d’enrichir les connaissances actuelles sur cette pathologie. / Hodgkin’s Lymphoma (HL) is one of the most frequent lymphomas occurring in childhood. In young children, there is a high predominance in boys and frequent association with Epstein-Barr Virus (EBV). Cohort studies have shown that patients affected by several immune deficiency syndromes - e.g. X-linked lymphoproliferative syndrome (XLP), functional deficit of Fas/FasL pathway and common variable immunodeficiency (CVID) - are risk factors of HL. We intend to search for qualitative and quantitative immune deficiencies as susceptibility factors to child's HL in a prospective study related to Euronet –PHL C1 protocol. Eighty-three patients at diagnosis of HL have been analysed. Median age of the study population is 13 years, (5-18 years). Gender-ratio M/F is 1.1 with a larger male predominance before the age of 10 (gender-ratio of 3). The search for a defect of NKT population that would be suggesting of XLP was negative in all patients. A moderate expansion of circulating TCRαβ+ double negative cells (DNT) has been detected in 5 patients. This expansion has been further explored in the hypothesis of a defect of Fas/FasL pathway by plasmatic quantification of Fas ligand and Il-10. This led to the exclusionof the diagnosis of ALPS. An unexpected high frequency of B-cell lymphopenia has been detected in 31 out of 83 patients (37%). Peripheral B cell lymphopenia was associated with the following poor prognostic factors: advanced stages (p<0.04), low hemoglobin (p<0.06) and B symptoms (p<0.01). B-cell lymphopenia was not statistically correlated with morphology (subtype, amount of tumor cells and necrosis). Remarkably, B-lymphocytic counts were significantly higher in patients with in situ EBV (<0.05).Only a B lymphopenia with low IgG level suggesting DICV was detected. We extended the analysis to all the 395 patients included in the protocol EURONET, so we identified 4 patients with CVID. These cases will be further explored by molecular analyses. In parallel, the specific T-cells response against EBV was studied by flow cytometry in 15 patients and ELISPOT assay in 9 patients with HL. Flow cytometry , suggested a decrease in production of IL-2 by CD4 T cells in patients with high EBV viral load in response to EBV latent and lytic-cycle peptides and autologous lymphoblatoid cells lines compared to controls or patients with LH-EBV-. The ELISPOT-IFNγ assay was used to determine the frequency of T cells that produced IFNγ in response to peptides. One patient demonstrated inappropriate EBV-specific T-cell IFNγ production (<10 IFNγ secreted T cells and >1,000 EBV copies per 250000 PBMCs). These cases will be further explored by molecular analyses.Our findings confirm the known epidemiological data of HL now mainly associated to NS subtype in children and adolescents and EBV status in HL at this age. We show that peripheral B cell lymphopenia in paediatric and adolescent HL patients is frequent and associated with poor prognosis factors. We confirm the association between CVID and HL.

L’immunité innée est notre premier mécanisme de défense contre l’invasion des pathogènes. Cette défense est basée sur la reconnaissance d’éléments invariables des pathogènes par des récepteurs encodés dans les lignées germinales. Dans la réponse anti-virale, le facteur de transcription Interferon Regulatory Factor 3 (IRF3) joue un rôle clé dans la réponse interféron de type I, combattant ainsi la réplication virale et conférant un état anti-viral aux cellules infectées ainsi qu’aux cellules avoisinantes. IRF3 est une protéine dont l’activation et la phosphorylation sont régulées par les kinases TBK1 et IKKi. Nous proposons ici que l’acétylation est une modification post-traductionnelle importante dans la régulation de l’activité d’IRF3. Nous avons observé par immunobuvardage qu’IRF3 est acétylé de façon basale et que cette acétylation est induite par la présence du co-facteur CBP et est inhibée par la présence de la kinase TBK1. Par spectrométrie de masse, nous avons ensuite identifié huit lysines sujettes à l’acétylation sur IRF3. Aussi, par mutagénèse dirigée, nous avons muté de façon ponctuelle chacun de ces sites et avons déterminé que la mutation de la lysine 87 inhibe la capacité d’IRF3 à s’attacher à l’ADN en EMSA et à transactiver son élément de réponse en essai luciférase. Aussi, nous proposons que l’acétylation masque la charge positive de la lysine 87 et contrôle de façon négative l’activité du facteur de transcription IRF3. Notre groupe démontre ainsi pour la première fois l’acétylation du facteur de transcription dans un modèle cellulaire et propose que ce processus joue un rôle inhibiteur dans la régulation de la protéine. / Innate immunity is our first line of defense against invading pathogens. This process is based on the recognition of invariable molecular patterns present on different pathogens by germ-line encoded receptors. In the innate immune response against invading viruses, the transcription factor Interferon Regulatory Factor 3 (IRF3) plays a major role in the regulation of type I interferons, priming the defense of infected and surrounding cells against viral infection. The phosphorylation and activation of IRF3 is regulated by the kinases TBK1 and IKKi. Here we suggest that acetylation is also an important post-translational modification in the regulation of this transcription factor. We have observed by immunoblot analysis a basal acetylation of IRF3, which is increased in the presence of its co-factor CBP and inhibited in the presence of its kinase TBK1. Also, we have identified on IRF3 eight different lysine residues subjected to acetylation using mass spectrometry and we have mutated these sites using sitedirected mutagenesis. We found that the K87R mutation inhibits IRF3-DNA binding in EMSA and leads to the transactivation of its promoter in luciferase assays. We also suggest that by masking the positive charge of the lysine 87 residue, acetylation negatively controls the activity of IRF3. Our group thus demonstrates for the first time the acetylation of IRF3 in a cellular model and suggests that this modification plays a role in the inhibition of the IRF3 transcription factor.