Aicardi-Goutières syndrome (AGS) is a rare inflammatory encephalopathy mimicking in utero acquired viral infection. Cardinal findings comprise leukodystrophy, basal ganglia calcifications and cerebral atrophy along with cerebrospinal fluid lymphocytosis and elevated interferon-α. In the majority of cases AGS is inherited as an autosomal recessive trait and caused by mutations in six genes including RNASEH2A, RNASEH2B, RNASEH2C, TREX1, SAMHD1 and ADAR1, all of which encode enzymes acting on nucleic acid species. Most patients present with first neurological signs in early infancy and experience severe global developmental delay. Here, we report on the unusual divergent phenotype of two siblings who both carry the most frequent AGS causing p.A177T (c.529G > A) RNASEH2B mutation in the homozygous state. While one sibling showed a typical AGS presentation with early onset and severe statomotor and mental impairment, the older sibling was intellectually completely normal. She was only diagnosed because of mild spasticity of the legs and serological signs of autoimmunity. These findings highlight the phenotypic variability of AGS and suggest that AGS may be underdiagnosed among children with mild cerebral palsy.

In this thesis, we have studied the immunological processes of joint inflammation that may be targets for future treatment of patients with arthritis. We focus on the immune-modulating properties of interferon-α (IFN-α) and uridine in experimental arthritis. The nucleoside uridine, which is regarded a safe treatment has anti-inflammatory properties notably by inhibiting tumor necrosis factor (TNF) release. Because the inflamed synovium in rheumatoid arthritis (RA) is characterised by pathogenic TNF-production, uridine could potentially be away to ameliorate arthritis. Systemic administration of uridine had no effect on antigeninduced arthritis (AIA), which is a T-cell dependent model where animals are immunized twice (sensitization) with bovine serum albumin (mBSA), before local triggering of arthritis by intra-articular antigen (mBSA) re-challenge. In contrast, intra-articular administration of uridine clearly down modulated development of AIA in a dose dependent manner and inhibited the expression of synovial adhesion molecules, influx of inflammatory leukocytes and synovial expression of TNF and interleukin 6, but did not affect systemic levels of proinflammatory cytokines or antigen-specific T-cell responses. Local administration of uridine may thus be a viable therapeutic option for treatment of arthritis in the future. Viral double-stranded deoxyribonucleic acid (dsRNA), a common nucleic acid found in most viruses, can be found in the joints of RA patients and local deposition of such viral dsRNA induces arthritis by activating IFN-α. Here we show that arthritis induced by dsRNA can be mediated by IFN-producing dendritic cells in the joint and this may thus explain why viral infections are sometimes associated with arthritis. Earlier, to study the effect of dsRNA and IFN-α in an arthritis model, that like RA, is dependent on adaptive immunity, dsRNA and IFN-α were administered individually during the development of AIA. Both molecules clearly protected against AIA in a type I IFN receptor-dependent manner but were only effective if administered in the sensitization phase of AIA. Here we show that the anti-inflammatory effect of IFN-α is critically dependent on signalling via transforming growth factor β (TGF-β) and the enzymatic activity of indoleamine 2,3 dioxygenase 1 (IDO). The IDO enzyme is produced by plasmacytoid DC and this cell type was critically required both during antigen sensitization and in the arthritis phase of AIA for the protective effect of IFN-α against AIA. In contrast, TGF-β and the enzymatic activity of IDO were only required during sensitization, which indicate that they are involved in initial steps of tolerogenic antigen sensitization. In this scenario, IFN- α first activates the enzymatic activity of IDO in pDC, which converts Tryptophan to Kynurenine, which thereafter activates TGF-β. Common for IDO-expressing pDC, Kyn and TGF-β is their ability to induce development of regulatory T cells (Tregs). We found that Tregs were crucial for IFN-α-mediated protection against AIA, but only in the arthritis phase. In line with this, adoptive transfer of Tregs isolated from IFN-α treated mice to recipient animals in the arthritis phase clearly protected against AIA. The numbers of Tregs were not significantly altered by IFN-α but IFN-α increased the suppressive capacity of Tregs against antigen-induced proliferation. This enhanced suppressive activity of Tregs in the arthritis phase was dependent on the earlier activated enzyme IDO1 during the sensitization phase of AIA. Thus, presence of IFN-α at the time of antigen sensitization activates the enzymatic activity of IDO, which generates Tregs with enhanced suppressive capacity that upon antigen re-challenge prevents inflammation. We have thus identified one example of how immune tolerance can be developed, that may be a future way to combat autoimmunity.

Ce travail de thèse s’est attaché à comprendre le lien étroit entre les dérégulations métaboliques et les dérégulations du système immunitaire, dans le cadre du modèle de diabète auto-immun de la souris NOD. Nous avons constaté que les bezafibrates protègent les souris NOD du diabète. Nous avons mis en évidence que ceci était lié à une diminution de l’infiltration des ilots beta du pancréas par les lymphocytes et cellules présentatrice d’antigen (CPA). La diminution d’IL-6 dans le sérum des souris traitées suggère une diminution générale de l’inflammation. Aussi, nous avons évalué l’implication du traitement en dehors du système immunitaire, en l’occurrence sur le stress cellulaire et la survie des cellules beta des ilots de Langherans, en utilisant une méthode de streptozotocine à faible dose, et nous avons observé une protection des souris traitées par les bezafibrates. Dans une deuxième partie de l’étude, nous avons observé qu’il existait au niveau du système immunitaire inné une surexpression des Toll-like récepteurs (TLR) 1, 2 et 6 dans les souris NOD comparées aux souris contrôles C57BL/6, ceci au niveau transcriptionnel ainsi qu’au niveau traductionnel. Nous avons ensuite démontré que cette surexpression avait une légitimité fonctionnelle. En effet, les CPA sécrètent plus d’Interleukine 6 (IL-6), et les cellules B, plus d’Immunoglobuline M (IgM). Nous avons poursuivi notre étude en modulant le contenu sérique en lipides dans nos souris NOD, en utilisant un régime gras pour augmenter la lipidémie et des bezafibrates hypolipidémiantes. Nous n’avons pas observé de modulation majeure de l’expression de TLR2 et TLR6, mais il est à noter que les CPA issues des souris soumises au régime gras sont plus susceptible à la réponse au ligand synthétique FSL-1 de TLR 2/6, qui sécrètent alors plus d’IL-6 que les NOD contrôles ou traitées aux bezafibrates. Nous avons pu ainsi souligner l’importance des liens entre le métabolisme et le système immunitaire, dans l’apparition de la maladie auto-immune que constitue le diabète de type 1. / In this thesis we sought to understand the link between metabolic deregulation and immune deregulation in the context of the NOD mouse autoimmune model. We observed that bezafibrates protect NOD mice from type 1 diabetes (T1D). We showed that pancreas beta islet infiltration by lymphocytes and APCs was diminished. IL-6 decrease in bezafibrate treated mice serum suggested a general dampening down of inflammation. Besides we evaluated the effect of bezafibrate out of the immune system by using a low-dose streptozotocin method and we observed that bezafibrate mice treated were protected. In a second part of this study we observed an overexpression of Toll-like receptors (TLR) 1, 2, 6 in NOD mice compared to C57BL/6 controls. This was noticeable at the transcription and translation level. We showed that this overexpression had a functional role. Indeed APCs from NODs secreted more IL-6, and B cells secreted more IgM when stimulated with corresponding ligands. We then modified the lipid content of NOD mice by using bezafibrates to decrease lipidemia, and a high fat diet (HFD) to increase lipidemia. No modulation of TLR2 and TLR6 expression was observed. However, APCs from HFD mice were more susceptible to TLR2/6 ligand FSL-1 stimulation by secreting more IL-6 than control or bezafibrate treated NODs. We here highlight the important links existing between metabolism immunity in the autoimmune T1D onset

La vaccination ADN à l’aide de plasmides codant pour des autoantigènes s’est avérée efficace dans la protection contre plusieurs maladies auto-immunes. Le but de ce mémoire était dans un premier temps d’établir si un protocole de vaccination ADN composé de 3 injections de pCMV-CTLA-4-NP et de pVR-IL-12 à deux semaines d’intervalle avait un effet protecteur contre le développement d’une hépatite auto-immune chez la souris TTR-NP, un modèle murin transgénique de la maladie et précédemment développé au laboratoire. Dans un deuxième temps, le but était d’élucider, le cas échéant, les mécanismes sous-tendant la protection conférée par la vaccination ADN. Les hypothèses initiales étaient qu’une protection allait effectivement être conférée par la vaccination ADN et que celle-ci pouvait être attribuable à une déviation de la réponse typiquement Th1 de la maladie vers une réponse Th2, à un épuisement des cellules immunitaires et/ou à l’activation et à l’induction de prolifération de cellules régulatrices. Les résultats montrent que la vaccination ADN induit une protection transitoire contre le développement d’infiltrations lymphocytaires au foie. Cette protection se ferait via un épuisement des cellules CD4+, CD8+ et CD19+ se retrouvant à la rate et exprimant PD 1 dans une plus forte proportion à 3 mois, et ne serait médiée ni par les lymphocytes T régulateurs CD4+CD25+FoxP3+, ni par les cellules CD8+FoxP3+. Une déviation de la réponse Th1 vers une réponse Th2 demeure une explication supplémentaire plausible à la protection conférée mais nécessiterait une caractérisation en situation plus physiologique avant de pouvoir inférer sur son implication réelle. La vaccination ADN n’influe ni sur la présence d’autoanticorps, ni sur les niveaux d’alanine aminotransférase, deux marqueurs de la maladie. / DNA immunizations were proven effective in a range of autoimmune diseases. The first goal of this master’s thesis was thus to evaluate if a protocol of 3 intramuscular plasmidic injections of pCMV-CTLA4-NP and pVR-IL-12, at 2 weeks apart, would protect TTR-NP mice, a transgenic murine model previously developed in the laboratory, against the development of an autoimmune hepatitis. The second goal was, if the protection was indeed conferred by DNA vaccination, to elucidate the mechanisms underlying this effect. The initial hypotheses were that DNA vaccination would indeed elicit a protection against autoimmune hepatitis, and that this could be attributed to a skew from the typical Th1 response to a more tolerogenic Th2 response, to the exhaustion of the immune cells and/or to the activation and the proliferation of regulatory T cells. Results show that DNA vaccination induces a transient protection against lymphocytic infiltrates in the liver. This protection is thought to be caused by the exhaustion of the CD4+, CD8+ and CD19+ cells found in the spleen and expressing PD-1 in greater proportion at 3 months, and not to be mediated by CD4+CD25+FoxP3+ or CD8+FoxP3+ regulatory T cells. An immunomodulation from a Th1 to a Th2 response could still be a plausible explanation by the protection conferred by the DNA vaccination, but additional experimentations in a more physiological setting would be necessary to infer on its real implication. DNA vaccination had no effect on autoantibodies or on alanine aminotransferase levels, which are two biological markers of the disease.

Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Biological and Medical Sciences Candidate: Bc. Barbora Zedníková Supervisor: Doc. MUDr. Josef Herink, DrSc. Title of diploma thesis: The role of the gut microbiome in immune-mediated CNS disorders Human body hosts a large number of microorganisms - i.e. Archea, Eukarya, Bacteria and viruses. These microorganisms form microbiome, the total number of the microorganisms is ten times higher than the number of all human cells. Largest part of the microbiome is located in the intestine. The current development of molecular genetics revealed the close relationship between intestinal microbiome and health. Recent studies the most recent studies have pointed to a connection with the pathogenesis of various diseases. This dissertation is focused on the connection between intestinal microbiome and autoimmune diseases of the central nervous system. Research shows that the key factor are the ongoing changes in the composition of microbiome. These changes lead to increased immune stimulation and thereby to inflammatory proliferation.

Le lupus érythémateux disseminé (LED) est une maladie chronique auto-immune caractérisée par la production d'autoanticorps dirigés contre les antigènes nucléaires. Des nombreuses études indiquent un rôle des récepteurs Toll-like (TLR). Des études antérieures de notre laboratoire ont révélé que le TLR8 murin contrôle la fonction de TLR7 dans les cellules dendritiques et est aussi impliqué dans le lupus. TLR9 contrôle également le lupus dépendant de TLR7. Mon projet de thèse avait deux objectifs dont le premier était de comprendre comment le TLR8 et TLR9 contribuent au lupus dépendant de TLR7. En outre, nous avons révélé que TLR8 contrôle l'expression de TLR7 dans les cellules dendritiques, tandis que le TLR9 contrôle la fonction de TLR7 dans les cellules B. Le deuxième objectif était d'étudier l'implication du répresseur transcriptionnel Gfi-1 dans la signalisation des TLR et le développement de lupus en utilisant des souris Genista qui portent une mutation ponctuelle dans le gène Gfi-1. Nous avons constaté que les souris Genista développent un lupus dépendant de TLR7 et que Gfi-1 agit comme un répresseur de la transcription en aval de TLR7 et contrôle l'expression d'Interféron de type I dépendante des TLR. Ainsi, le déséquilibre des interactions entre TLR ainsi que les facteurs transcriptionnels en aval de ces TLR peuvent conduire à des mécanismes d'inflammation et d'auto-immunité qu'il est important de prendre en compte dans le développement d'approches thérapeutiques nouvelles ciblant les TLRs. / Systemic lupus erythematosus is a chronic autoimmune disease characterized by production of autoantibodies against nuclear antigens. Many studies indicate a role for Toll-like receptors (TLRs) in the initiation and establishment of systemic lupus erythematosus (SLE). Previous studies in the lab revealed that murine TLR8 controls TLR7 function in dendritic cells (DCs) and is implicated in SLE. TLR9 also controls TLR7-mediated lupus. My thesis had two aims: the first was to understand how the cooperation of TLR8 and TLR9 contributes to TLR7-mediated lupus. By studying double TLR8/9-deficient mice we found that TLR8 and TLR9 have an additive effect on controlling TLR7-mediated lupus, where TLR8 controls TLR7 function on DCs, while TLR9 restrains TLR7 responses in B cells. The second aim of my thesis was to investigate the implication of Gfi-1 in lupus and TLR signaling by studying Genista mice that carry a hypomorphic mutation of Gfi-1. We found that Genista mice develop TLR7-dependent lupus and that Gfi-1 acts as a transcriptional repressor downstream of TLR7 and controls type-I IFN expression. Thus, unbalancing TLR-interactions and transcription factors downstream of TLRs can lead to inflammation and autoimmunity and these mechanisms have to be taken into account when novel therapeutic approaches are developed that target TLRs.

Summary: This diploma thesis deals with the relation between autoimmune processes at biological level (through proven neurological autoimmune disease - multiple sclerosis) and possible autoaggressive processes at the mental level. It is divided into several points. The first one introduces human immunity in general. The first part is followed by immune system description, including autoimmunity and the principle of diseases of this system. Thereafter, psychological aggression is described, in which the division into aggression and auto- aggression fits. This is followed by chapters on projective psychodiagnostics taking into account the detection of various forms of aggression. Then, the thesis focuses on the study of possible auto-aggressive manifestations in patients suffering from the most widespread neurological autoimmune disease, multiple sclerosis. The second half of the thesis describes the author's research on this topic.

O objetivo do projeto foi desenvolver linhagens celulares para um anticorpo terapêutico anti-hTNFα e comprovar sua funcionalidade. Os genes anti-hTNFα foram clonados em células CHO para seleção da população estável mista, demonstrando expressão de anticorpo com reconhecimento de hTNFα em estrutura tridimensional. A população de transfectantes de maior produtividade específica foi escolhida para geração de linhagem monoclonal utilizando a tecnologia robótica ClonePix FL. Não houve diferença estatística entre o anti-hTNFα purificado e o produto de referência na cinética de ligação ao TNFα e reconhecimento diferencial por FcγRs em ensaios por SPR O ensaio de atividade funcional mostrou que o anti-TNFα desenvolvido pôde neutralizar a citotoxicidade induzida em células L929 e inibir a expressão de ELAM-1 em HUVEC. Os resultados finais permitiram identificar os três melhores clones, estáveis por 60 gerações. A comparabilidade entre o anti-TNFα desenvolvido e a referência permite admiti-lo como não inferior, um dos requisitos para o desenvolvimento de biossimilar. / The aim of the project was to develop a therapeutic anti-hTNFα antibody and evaluate its functionality. The anti-hTNFα synthezised genes were cloned into CHO cells and stable pools were selected, producing antibodies able to hTNFα three-dimensional structure recognition. The stable pools displaying higher antibody yields were the source for the generation of monoclonal lineage by ClonePix FL robotic technology. The clones selection proceeded using different criteria as cell density, specific productivity, fed-batch performance, kinetics measured by surface plasmonic resonance, hTNFα binding through ELISA, western-blotting and SPR, FcγRs binding by SPR. Besides, a small number of clones was tested in functional assays by the impairment of cytotoxicity of hTNFα over L929 cells and the inhibition of ELAM-1 expression by HUVEC. The long term stability testing allowed to finally select 3 top clones, not inferior to adalimumab reference by the above criteria.

A deficiência de imunoglobulina A (DIgA) é a imunodeficiência primária mais comum com prevalência de 1: 223 a 1:1000 em estudos epidemiológcos, sendo menos freqüente em populações asiáticas. As manifestações clínicas variam desde indivíduos assintomáticos até aqueles com manifestações atópicas, auto-imunes ou infecciosas. Entre estas últimas destacam-se os acometimentos dos tratos respiratório e digestório. Associação com outras imunodeficiências primárias tem sido reportada, em especial a imunodeficiência comum variável e a deficiência de subclasses de imunoglobulina G. Os objetivos deste estudo foram a avaliação dos pacientes com DIgA, diagnosticados na infância, após a segunda década da vida e a avaliação diagnóstica de seus familiares quanto aos aspectos clínicos e laboratoriais. A metodologia utilizou, para o diagnóstico de DIgA, o critério adotado pelo ESID/PAGID (1999). Foi realizada a avaliação das concentrações de imunoglobulina A(IgA) e imunoglobulina M (IgM), na saliva e a pesquisa de auto-anticorpos séricos (Anti-tireóide, FR,FAN) nos pacientes e familiares com DIgA. Realizou-se uma curva de distribuição de IgM salivar em indivíduos normais para comparação com os pacientes DIgA. Os resultados mostraram a avaliação dos 34 pacientes (19 do sexo feminino) com deficiência de imunoglobulina A (DIgA) com idade superior a 10 anos (variação: 10 à 52 anos), sendo 27 deles diagnosticados na infância e 7 familiares dos 62, que responderam à convocação. Considerando-se todos os indivíduos com DIgA, processos infecciosos (de repetição ou graves) ocorreram em 91,2%, manifestações atópicas em 58,8% e auto-imunidade em 52,9%. Manifestações clínicas de auto-imunidade foram observadas em 14/18 indivíduos, sendo que sete foram diagnosticados após 10 anos de idade, por ocasião da realização da pesquisa. Auto-anticorpos foram observados em 10 pacientes, sendo quatro pacientes assintomáticos. Fator reumatóide não foi detectado nesta casuística. Tireoidopatias (seis casos) e artropatias (quatro casos) foram as manifestações clínicas auto-imunes mais observadas. As concentrações de IgM salivar mostraramse elevadas em todos, exceto cinco casos. A comparação dessas concentrações nos grupos com e sem auto-imunidade não mostrou diferença significante (p= 0,48). As conclusões desta pesquisa mostraram os processos infecciosos como as manifestações clínicas mais freqüentes nos pacientes com DIgA, observando-se, porém, uma relevante presença de auto-imunidade nestes pacientes quando reavaliados após a segunda década de vida. Este fato alerta para a necessidade de avaliação rotineira de fenômenos auto- imunes nestes pacientes, durante seguimento. As concentrações de IgM salivar foram semelhantes em pacientes com DIgA com e sem auto-imunidade. Auto-anticorpos foram detectados independentemente da presença de sintomatologia clínica, sendo os mais encontrados aqueles relacionados à tireóide. Os familiares de primeiro grau dos pacientes com DIgA devem ser avaliados, tanto para diagnóstico de imunodeficiências como para detecção de fenômenos auto-imunes, permitindo assim o diagnóstico e abordagens precoces de ambas condições. / IgA deficiency (IgAD) is the most frequent primary immunodeficiency. Its prevalence varies from 1:223 to 1:1000 in epidemiological studies, but in asiatic populations it is uncommon. The clinical manifestations of IgAD are spectral, ranging from asymptomatic patients to recurrent infections, allergic symptoms and/or autoimmunity conditions. The most common infections frequently associated to IgAD involve respiratory and gastrointestinal tracts. The association with other primary immunodeficiency such as common variable immunodeficiency and immunoglobulin G subclasses deficiency has been reported. The aim of this study is to describe clinical and laboratorial evolution regarding autoimmune manifestations in IgAD patients diagnosed during the first years of life and after the second decade and their relatives diagnosed during this study. Laboratorial data included immunoglobulins A and M levels in saliva and auto-antibody screening in immunoglobulin A deficient relatives and patient. The criterion adopted for IgAD diagnosis was defined by Pan-American Group for Immunodeficiency and European Society for Immunodeficiency. The results showed 34 (19 female) immunoglobulin A deficient patients (IgAD) over 10 years of age (range: 10-52 years), 27 of them diagnosed during their childhood, and seven adults detected among 62 screened relatives. Recurrent infections were diagnosed in 91.2% of cases, atopic manifestations in 58.8% and autoimmune clinical manifestation in 52.9%. Autoimmune clinical manifestations were observed in 14 of our 18 IgA deficient patients and relatives with autoimmunity phenomena and seven of them diagnosed only over 10 years old during the study. Auto-antibodies were observed in (10/18) of patients and relatives, with four of them (asymptomatic) showing only the presence of auto-antibodies. Thyroid and osteo-articular involvement (six and four cases, respectively) were the most frequent clinical autoimmune manifestations. The rheumatoid factor was not detected in this casuistic. Auto-antibodies had no statistical difference among patients with or without autoimmunity phenomena. High salivary IgM concentrations were detected in all IgA deficient patients and relatives, except five cases. The comparison of these concentrations in the groups with and without autoimmunity did not show significant difference (p=.0, 48). In conclusion, recurrent infections were the most frequent clinical manifestations of IgA deficient patients and also autoimmune diseases, after the second decade of life. This fact at this series reinforced the necessity of active search for autoimmune conditions diagnosis in these patients. IgM levels showed no statistical difference among IgA deficient patients and relatives with or without autoimmunity. Auto-antibodies, mainly anti-thyroid antibodies, were detected in patients independently of autoimmunity clinical manifestation presence. This study showed the importance of the first degree relatives of IgA deficient patients evaluation, focusing as immunodeficiency as autoimmune disease, permiting an earlier diagnosis of both conditions and an adequate approach to optimize the clinical management and improvement of quality of life of IgAD patients.

Ensaios clinicos tem demonstrado que a imunossupressao em altas doses (IAD) seguida de transplante autologo de celulas tronco hematopoeticas (TACTH) e capaz de suprimir a atividade inflamatoria em pacientes com doencas autoimunes (DAIs) e induzir remissoes clinicas prolongadas nesses pacientes, porem os mecanismos de acao do TACTH ainda nao estao bem esclarecidos. O racional dessa terapia baseia-se na eliminacao das celulas autorreativas pela IAD e na reconstituicao de um sistema imunologico novo e tolerante apos o transplante a partir dos precursores hematopoeticos. O objetivo deste trabalho foi avaliar a reconstituicao imunologica em pacientes com diabetes mellitus tipo 1 (DM1, N=21) e pacientes com esclerose multipla (EM, N=37) sequencialmente apos o TACTH, e correlacionar os dados imunologicos com a resposta clinica dos pacientes ao transplante. Os pacientes com EM e DM1 foram divididos em dois grupos com base na resposta clinica apos o transplante: respondedores (EM-R; N=22) e nao-respondedores (EM-NR; N=15); livres de insulina por periodo maior ou igual a 3 anos (DM13 anos; N=11) e livres de insulina por periodo menor que 3 anos (DM1<3 anos; n=10); e acompanhados clinica e imunofenotipicamente por seis anos. Em relacao ao periodo pre-transplante, todos os grupos de pacientes com DM1 e EM apresentaram: 1, diminuicao do numero absoluto de celulas T CD3+ praticamente em todos os periodos pos-transplante avaliados, indicando uma intensa linfopenia decorrente da IAD; 2, aumento acentuado do numero de linfocitos T CD8+ e a diminuicao dos linfocitos T CD4+, resultando na inversao da razao CD4:CD8 durante todo o seguimento pos-transplante avaliado; 3, aumento significativo no primeiro ano apos o transplante das subpopulacoes de celulas T CD8+ de memoria central CD27+CD45RO+ e memoria efetora CD27- CD45RO+; 4, normalizacao dos numeros de linfocitos T CD4+ e CD8+ naive CD27+CD45RO- somente cinco anos apos o transplante, enquanto o numero de celulas T CD4+CD45RA+CD31+ recem- emigrantes do timo manteve-se abaixo dos valores pre-transplante durante todo o periodo avaliado, demonstrando que durante os seis anos de seguimento apos a IAD/TACTH predominaram mecanismos timo-independentes de reconstituicao imunologica; 5, normalizacao dos numeros de linfocitos B CD19+ entre dois a tres meses pos-transplante. O grupo de pacientes com DM1 que obteve melhor resposta clinica apos o tratamento com IAD/TACTH (DM13anos) apresentou, em comparacao ao periodo pre-transplante, numero diminuido de celulas T CD3+ (linfopenia) em varios periodos pos-transplante, numero aumentado de celulas T CD8+CD28- supressoras no primeiro ano pos-transplante principalmente, numero diminuido de celulas T CD4+ de memoria efetora nos periodos 2 a 9 meses pos-transplante e numero aumentado de celulas T reguladoras CD4+CD25hiFOXP3+ pos-transplante. O grupo de pacientes com EM com melhor resposta clinica apos o tratamento com IAD/TACTH (EM-R) apresentou, em comparacao ao periodo pre-transplante, numero diminuido de celulas T CD3+ (linfopenia) em varios periodos pos-transplante e numeros aumentados de celulas T reguladoras CD4+CD25hiFOXP3+ e CD8+CD28- supressoras nos primeiros tres anos pos-transplante. Vale ressaltar que os pacientes com DM1 e EM que apresentaram melhor resposta clinica permaneceram linfopenicos por maiores periodos de tempo apos o transplante. Desse modo, esse estudo revelou que a resposta terapeutica dos pacientes com DM1 e EM ao TACTH depende de uma linfopenia persistente, alem do aumento de celulas T reguladoras e supressoras e diminuicao de celulas T CD4+ de memoria apos o transplante. / Clinical trials have shown that high-dose immunosuppression (HDI) followed by autologous hematopoietic stem cell transplantation (AHSCT) is able to suppress the inflammatory activity in patients with autoimmune diseases (AID) and induce prolonged clinical remissions in these patients, but the mechanisms of action of AHSCT are still not well understood. The rationale of this therapy is based on the elimination of autoreactive cells by HDI and on the reconstitution of a new tolerant immune system after transplantation from hematopoietic precursors. The aim of this study was to evaluate the immune reconstitution in patients with type 1 diabetes mellitus (T1D, N=21) and patients with multiple sclerosis (MS, N=37) sequentially after the AHSCT, and correlate the immunological data with the clinical response of these patients to the transplant. Patients with MS and T1D were divided into two groups based on clinical response following transplantation: response (MS-R, N=22) and non-response (MS-NR, N=15); insulin-free for a period longer or equal to 3 years (T1D3 years, n=11) and insulin-free for less than 3 years (T1D<3 years, n=10); and accompanied clinical and immunophenotypically by six years. Regarding the pre-transplant period, all groups of patients with T1D and MS showed: 1, decreased absolute number of CD3+ T cells in virtually all post-transplant periods evaluated, indicating an intense lymphopenia resulting from HDI; 2, sharp increase in the number of CD8+ T lymphocytes and decreased CD4+ T lymphocytes, resulting in inversion of CD4:CD8 ratio throughout the follow-up post-transplant evaluation; 3, a significant increase, in the first year after transplantation, of CD8+ T central memory CD27+CD45RO+ and effector memory CD27-CD45O+ cell subpopulations; 4, normalization of CD4+ and CD8+ T naive CD27+CD45RO- lymphocytes numbers only five years after transplantation, whereas the number of CD4+CD45RA+CD31+ T cells newly emigrants from the thymus remained below the values pre- transplant during the study period, showing that during the six years of follow-up after the HDI/AHSCT mechanisms thymus-independent immune reconstitution were predominant; 5, normalization of CD19+ B lymphocytes numbers in two to three months post-transplant. The group of patients with DM1 that had the best clinical response after treatment with IAD/AHSCT (T1D 3years) showed, in comparison with the pre-transplant period, decreased number of CD3+ T cells (lymphopenia) at various times after transplantation, increased CD8+CD28- suppressor T cells numbers in the first year post-transplant, decreased number of CD4+ effector memory in periods of 2 and 9 months post-transplant and increased number of CD4+CD25hiFOXP3+ regulatory T cells after transplantation. The group of MS patients with better clinical response after treatment with IAD/AHSCT (MS-R) showed, in comparison to the pre-transplant period, decreased number of CD3+ T cells (lymphopenia) at various times after transplantation and increased numbers of CD4+CD25hiFOXP3+ regulatory Tcell and CD8+CD28- suppressor in the first three years post- transplant. It is noteworthy that patients with T1D and MS which showed better clinical response remained lymphopenic for longer periods of time after transplantation. Thus, this study revealed that the therapeutic response of patients with T1D and MS depend on a AHSCT to persistent lymphopenia, and increased regulatory and suppressor T cells and decreased number of CD4+ effector memory after transplantation.