Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 5 uppsatser.

BACKGROUND:Marek's Disease (MD) is a hyperproliferative, lymphomatous, neoplastic disease of chickens caused by the oncogenic Gallid herpesvirus type 2 (GaHV-2 / MDV). Like several human lymphomas the neoplastic MD lymphoma cells overexpress the CD30 antigen (CD30hi) and are in minority, while the non-neoplastic cells (CD30lo) form the majority of population. MD is a unique natural in-vivo model of human CD30hi lymphomas with both natural CD30hi lymphomagenesis and spontaneous regression. The exact mechanism of neoplastic transformation from CD30lo expressing phenotype to CD30hi expressing neoplastic phenotype is unknown. Here, using microarray, proteomics and Systems Biology modeling / we compare the global gene expression of CD30lo and CD30hi cells to identify key pathways of neoplastic transformation. We propose and test a specific mechanism of neoplastic transformation, and genetic resistance, involving the MDV oncogene Meq, host gene products of the Nuclear Factor Kappa B (NF-kappaB) family and CD30 / we also identify a novel Meq protein interactome.RESULTS:Our results show that a) CD30lo lymphocytes are pre-neoplastic precursors and not merely reactive lymphocytes / b) multiple transformation mechanisms exist and are potentially controlled by Meq / c) Meq can drive a feed-forward cycle that induces CD30 transcription, increases CD30 signaling which activates NF-kappaB, and, in turn, increases Meq transcription / d) Meq transcriptional repression or activation of the CD30 promoter generally correlates with polymorphisms in the CD30 promoter distinguishing MD-lymphoma resistant and susceptible chicken genotypes e) MDV oncoprotein Meq interacts with proteins involved in physiological processes central to lymphomagenesis.CONCLUSIONS:In the context of the MD lymphoma microenvironment (and potentially in other CD30hi lymphomas as well), our results show that the neoplastic transformation is a continuum and the non-neoplastic cells are actually pre-neoplastic precursor cells and not merely immune bystanders. We also show that NF-kappaB is a central player in MDV induced neoplastic transformation of CD30-expressing lymphocytes in vivo. Our results provide insights into molecular mechanisms of neoplastic transformation in MD specifically and also herpesvirus induced lymphoma in general.

Marek’s disease (MD) of chickens is an economically important, contagious, neoplastic disease caused by Gallid herpesvirus type 2. All chicken are susceptible to MDV infection and neoplastic transformation, but, only susceptible genotypes develop gross lymphomas. Lymphomas regress in resistant genotypes from 21 days post infection (dpi). The central aims of this study were to understand the mechanisms of non-MHC associated genetic resistance and the molecular pathways of neoplastic transformation. We hypothesized that, a) in resistant chickens at 21 dpi the tissue microenvironment is compatible with cell mediated immunity but in susceptible lines antagonistic to cell mediated immunity, b) resistant genotypes present immunogenic peptides on their MHC class I which while the peptides presented by susceptible genotypes do not induce CTL immunity resulting in tumor progression. We used inbred, MHC homozygous MD resistant (L6) and susceptible (L7) chickens and reductionist methods to test our hypotheses. Our results indicated that the tumor microenvironment is pro T-regulatory in both resistant and susceptible genotypes, and, the host immune response (pro Th-1 in resistant and pro Th-2/T-reg in susceptible) influences the tumor regression or progression. Statistical analysis of MHC class I bound peptides from resistant and susceptible genotypes confirmed that they present the same peptides and perhaps genes outside the MHC locus play an important role in determining resistance. Next, using Systems Biology tools like genomics, proteomics, Gene Ontology modeling and pathway analysis we compared the transcriptome and proteome of neoplastically transformed cells (CD30hi) and non-neoplastically transformed cells (CD30lo) which are the two components of tumor microenvironment. We demonstrated that: a) in situ, CD30lo cells are pre-neoplastic and the proteome involved in transformation and potential mechanisms that may be controlled by MDV oncogene Meq; b) Meq can drive a feed forward loop that induces CD30 transcription and overexpression, increased CD30 signaling, which then activates NFêB and, in turn, increases Meq transcription; c) Meq transcriptional repression or activation from the CD30 promoter generally correlates with a polymorphism in the CD30 promoter between MD-resistant and -susceptible chicken genotypes and so a herpesvirus has evolved to utilize NFêB as a direct transcriptional activator for its oncogene.

In der vorliegenden Arbeit wurden Lymphoproliferationen und maligne Non-Hodgkin-Lymphome der B-Zellreihe, die eine Infektion der Tumorzellen mit dem Epstein-Barr Virus aufwiesen, hinsichtlich ihres Immunphänotyps und ihrer zytogenetischen Aberrationen durch Fluoreszenz in-situ Hybridisierung charakterisiert. Von besonderer Bedeutung war es, durch eine detaillierte Analyse der klinischen Daten Vorerkrankungen/Zweiterkrankungen mit einer möglichen Immunsuppression zu identifizieren. Die erhaltenen Daten wurden mit denen EBV-negativer diffuser grosszelliger B-Zell Lymphome verglichen. In der Gewebe-Array-Technik konnten letztlich 69 Fälle detailliert charakterisiert werden. Von 53/69 (77%) dieser Lymphoproliferationen, die sämtlich eine EBV-Assoziation aufwiesen, konnten klinische Daten erhalten werden. Die detaillierte Analyse dieser Daten zeigte, dass in der grossen Mehrzahl der Fälle eine für eine EBV-Infektion prädisponierende Vor- bzw. Grunderkrankung vorlag (44/69 Fälle, 64%). Dabei handelte es sich in 9 Fällen um eine HIV-Infektion, in 12 Fällen um eine Post-Transplantations lymphoproliferative Erkrankung, in 19 Fällen um einen Zustand nach vorangegangener, therapierter Lymphomerkrankung und in vier Fällen um einen Zustand bei Methotrexatbehandlung oder vergleichbarer medikamentöser Immunsuppression. In neun Fällen war nachweislich keine zu einer möglichen Immunsuppression führende Grunderkrankung eruierbar; diese Tumoren, die bei Patienten mit einem Durchschnittsalter von 72,7 Jahren auftraten, entsprechen wahrscheinlich den in der Literatur beschriebenen „senilen“ EBV-assoziierten Lymphoproliferationen, bei denen eine durch das fortgeschrittenen Lebensalter bedingt reduzierte Fähigkeit des Immunsystems zu einer adäquaten Viruskontrolle diskutiert wird. Klinische Angaben, die auf eine mögliche Immunsuppression und damit auf eine mögliche EBV-Assoziation hindeuten, lagen zum Zeitpunkt der Vorstellung des Falles im Referenzzentrum bemerkenswerterweise nur in 26/69 Fällen (38%) vor.EBV-assoziierte Lymphoproliferationen und Lymphome gehören signifikant häufiger dem (immunhistochemisch definierten) non-GCB-Subtyp als dem GCB-Subtyp der DLBCL an (73% versus 37%; p<0,0001). Hier lag ein zusätzlicher interessanter Aspekt vor: EBV-assoziierte Lymphoproliferationen, die aufgrund ihrer Reaktivität der Tumorzellen für CD10 dem GCB-Typ zugeordnet worden waren, exprimierten nur in einer Minderzahl der Fälle (1 von 12; 8%) gleichzeitig auch BCL-6, ein Befund, der bei sporadischen, EBV-negativen DLBCL nur äußerst selten zu finden war (1 von 50; 2%). Weitere immunhistochemische Unterschiede zwischen EBV-assoziierten und EBV-negativen DLBCL lagen für die Expression des Aktivierungsmarkers CD30, der bei EBV-negativen DLBCL eher selten exprimiert wird, aber bei EBV-positiven DLBCL/-Lymphoproliferationen signifikant häufiger positiv ist, und auch für CD138 vor. Auch dieser Marker einer plasmazellulären Differenzierung war bei EBV-positiven DLBCL häufiger exprimiert, wohingegen die Expression von BCL-2 und BCL-6 in den Tumorzellen EBV-assoziierter LPD seltener war. Der häufigere non-GCB-Status, die vermehrte Expression von CD138 und die geringere Reaktivität für BCL-6 legen nahe, dass EBV-assoziierte DLBCL/Lymphoproliferationen offensichtlich aus B-Zellen bestehen oder hervorgegangen sind, die die Keimzentrumsreaktion bereits durchlaufen hatten. Die Analyse der interphasenzytogenetischen Daten und ihr Vergleich zu klassischen zytogenetischen Daten einer Kontrollgruppe von sporadischen DLBCL zeigte, dass chromosomale Bruchereignisse und auch eine TP53 Mutation (ausgewiesen durch die immunhistochemisch nachgewiesene Überexpression des Gens) nur bei denjenigen Fällen auftrat, die konventionell-morphologisch als DLBCL charakterisiert worden waren. Im Vergleich zur Kontrollgruppe wurde eine signifikant häufigere Rearrangierung von CMYC in EBV-assoziierten DLBCL gefunden; im Gegensatz hierzu waren Bruchereignisse im BCL2- und im BCL6-Locus ohne signifikanten Unterschied zur Kontrollgruppe. Als „Nebenbefund“ konnte in dieser Studie eine Infektion eines – offenbar primär nodalen – DLBCL vom immunoblastisch-plasmoblastischen Subtyp bei einem HIV-positiven Patienten durch das humane Herpesvirus 8 (HHV8) nachgewiesen werden. Diese Konstellation stellt insofern eine Rarität dar, da HHV8-positive DLBCL zumeist extranodal, z.B. in Form des sogenannten „Primären Effusions-Lymphoms“ (PEL) oder in Assoziation zu einer multizentrischen Castleman-Erkrankung bei HIV-positiven Patienten auftreten. / This study characterizes the immunophenotype and genetic aberrations (that were identified by fluorescence in situ hybridization) of Epstein-Barr-virus (EBV)-associated lymphoproliferations and non-Hodgkin lymphomas of B-cell origin.These data were compared with the data of EBV-negative diffuse, large B-cell lymphomas(DLBCL). Further, for the EBV-positive cases clinical data were evaluated.The clinical data showed that in most cases there was a specific kind of immunosuppression(e.g. previous tumors, HIV-infection, organ transplantation, iatrogenic immunosuppression by methotrexate) that correlates by cause with the EBV-infected lymphomas. In nine cases it has been proved that the patients had no kind of immunosuppression. These patients were all elderly (average 72,7 years) and their lymphomas and lymphoproliferations were classified as “ senile lymphoproliferations” (according to Shimoyama et al., 2006) where due to seniority a reduction of immunosystem is discussed. Results: The EBV-associated lymphoproliferations and lymphomas displayed a distinct immunophenotype. Compared to the de novo DLBCL they showed significantly more often the non-GCB-subtype. Interestingly, the EBV-positive lymphoproliferations which showed the CD10-positive GCB-subtype were only positive for bcl-6 in one case (8%), which is very unusual. The EBV-positive lymphoproliferations and lymphomas showed also significantly more expression of the activation protein CD30 and the plasma cell marker CD138 but less expression of bcl-2 and bcl-6. The oncogene MYC was significantly more often rearranged. As an additional result of this study a HHV8/EBV coinfection was found in an immunoblastic-plasmablastic DLBCL which occured in a cervical lymph node of a HIV-positive young male. This is a very rare finding because HHV8-positive DLBCL mainly occur at extranodal sites, e.g. as primary effusion lymphoma or in association with a multicentric Castleman disease, both often in the setting of immunodeficiency.

GITR and CD30 are T cell costimulatory members of the TNFR superfamily known to regulate T cell responses. Elucidating the mechanisms whereby these receptors modulate T cell responses is crucial for maximizing their potential for immunotherapy. In this thesis, I examine the role of GITR and CD30 on CD8 T cell responses to influenza virus. I show that CD8 T cell intrinsic GITR is required for both maximal primary and secondary CD8 T cell expansion to influenza, while in contrast, CD30 is dispensable for anti-influenza CD8 T cell responses. GITR does not impact on CD8 T cell proliferation or homing, however, it mediates CD8 T cell survival signaling. GITR induces TRAF2/TRAF5 dependent, but TRAF1 independent, NF-κB activation, resulting in the upregulation of the pro-survival molecule Bcl-xL. Furthermore, I show that GITR on CD8 T cells can augment viral clearance and confer protection from death upon severe influenza infection of mice. Similarly, CD30 also elicits protection from death upon severe influenza infection, although the cells responsible for this effect remain to be elucidated. In this thesis, I also show that in unimmunized mice GITR expression is upregulated to higher than basal levels on a population of CD8 memory phenotype cells in the bone marrow. In contrast, CD8 memory phenotype T cells in the spleen and LN have GITR levels similar to that on naïve T cells. The upregulation of GITR in the bone marrow is IL-15 dependent and therefore, GITR serves as a marker for cells that have recently received an IL-15 signal. Furthermore, GITR is required for the persistence, but not for the homeostatic proliferation of CD8 memory phenotype T cells in the bone marrow. Therefore, GITR plays a key role for CD8 T cell intrinsic responses to influenza, as well as for the persistence of CD8 memory phenotype T cells.

GITR and CD30 are T cell costimulatory members of the TNFR superfamily known to regulate T cell responses. Elucidating the mechanisms whereby these receptors modulate T cell responses is crucial for maximizing their potential for immunotherapy. In this thesis, I examine the role of GITR and CD30 on CD8 T cell responses to influenza virus. I show that CD8 T cell intrinsic GITR is required for both maximal primary and secondary CD8 T cell expansion to influenza, while in contrast, CD30 is dispensable for anti-influenza CD8 T cell responses. GITR does not impact on CD8 T cell proliferation or homing, however, it mediates CD8 T cell survival signaling. GITR induces TRAF2/TRAF5 dependent, but TRAF1 independent, NF-κB activation, resulting in the upregulation of the pro-survival molecule Bcl-xL. Furthermore, I show that GITR on CD8 T cells can augment viral clearance and confer protection from death upon severe influenza infection of mice. Similarly, CD30 also elicits protection from death upon severe influenza infection, although the cells responsible for this effect remain to be elucidated. In this thesis, I also show that in unimmunized mice GITR expression is upregulated to higher than basal levels on a population of CD8 memory phenotype cells in the bone marrow. In contrast, CD8 memory phenotype T cells in the spleen and LN have GITR levels similar to that on naïve T cells. The upregulation of GITR in the bone marrow is IL-15 dependent and therefore, GITR serves as a marker for cells that have recently received an IL-15 signal. Furthermore, GITR is required for the persistence, but not for the homeostatic proliferation of CD8 memory phenotype T cells in the bone marrow. Therefore, GITR plays a key role for CD8 T cell intrinsic responses to influenza, as well as for the persistence of CD8 memory phenotype T cells.

O CD30 solúvel (CD30s) é uma glicoproteína transmembrana da família do fator de necrose tumoral expressa na superfície das células T. Quando este marcador é clivado ele torna-se solúvel, sendo detectado na circulação. Atualmente, o valor de CD30s pré-transplante vem sido demonstrado como um bom preditor de rejeição aguda (RA) e perda do enxerto. Poucos estudos foram realizados para sua avaliação no pós-transplante e sua correlação com sobrevida e TFG. Avaliar a eficácia da determinação dos marcadores laboratoriais CD30 solúvel (CD30s) e anticorpos reativos contra painel HLA (PRA) em seis meses, um ano e seis anos pós-transplante renal em receptores de doadores vivos, correlacionando estes marcadores com episódios de rejeição aguda, eventos infecciosos no pós-transplante, perda do enxerto e óbito do paciente transplantado. E, avaliar a correlação destes marcadores com a sobrevida do enxerto renal nestes períodos. Os pacientes estudados foram transplantados renais com doadores vivos no Hospital Federal de Bonsucesso (HFB) do Rio de Janeiro no ano de 2006 e do período de agosto de 2010 a maio de 2011, sendo uma extensão de um trabalho realizado previamente. CD30s e PRA foram analisados nas amostras coletadas no pré-transplante e com 7, 14, 21 dias, 1, 3, 6, 12 meses após o transplante e nos pacientes transplantados em 2006 amostras após 6 anos de transplante. A taxa de filtração glomerular (TFG) foi estimada utilizando MDRD e CKD-epi e 6 meses, 1 ano e 6 anos após o transplante. Os pacientes foram agrupados em 5 grupos: sem eventos, com perda do enxerto, óbito, rejeição aguda e pacientes com quadros infecciosos. Estes grupos foram avaliados com relação ao CD30s, PRA I e II e comparados dois a dois. O teste qui quadrado foi utilizado. Quando necessário aplicou-se a correção de Yates, o teste de Fisher, o teste de Kruskal-wallis. Foi considerado estatisticamente significante p<0,05. As análises foram feitas pelo programa EPI-Info (versão 3.5.3). Setenta e seis pacientes com doadores vivos foram incluídos no estudo 47 pacientes não tiveram nenhum evento (grupo 1), 7 pacientes perderam o enxerto (grupo 2), 3 pacientes faleceram (grupo 3), 11 pacientes ficaram no grupo de rejeição aguda (grupo 4) e oito pacientes tiveram infecção por CMV e herpes (grupo 5). Os pacientes do grupo de RA tiveram correlação positiva com os valores tanto de CD30s Pré-transplante (p=0,01), quanto do CD30s pós-transplante (p=0,002) e PRA I e II (p<0,001), respectivamente, quando comparados com pacientes sem eventos. A TFG tanto com MDRD e CKD-Epi não mostrou correlação com CD30s pré e pós-transplante e nem PRA I e II. A TFG com as duas fórmulas foi menor no grupo com RA comparado com o grupo sem evento após 6 anos de transplante (p=0,006). CD30s é um bom preditor de RA, assim como PRAI e II. E, também mais uma ferramenta que pode ser utilizada no acompanhamento pós-transplante Renal. A RA é um preditor isolado para diminuição de TFG no transplante.

O CD30 solúvel (CD30s) é uma glicoproteína transmembrana da família do fator de necrose tumoral expressa na superfície das células T. Quando este marcador é clivado ele torna-se solúvel, sendo detectado na circulação. Atualmente, o valor de CD30s pré-transplante vem sido demonstrado como um bom preditor de rejeição aguda (RA) e perda do enxerto. Poucos estudos foram realizados para sua avaliação no pós-transplante e sua correlação com sobrevida e TFG. Avaliar a eficácia da determinação dos marcadores laboratoriais CD30 solúvel (CD30s) e anticorpos reativos contra painel HLA (PRA) em seis meses, um ano e seis anos pós-transplante renal em receptores de doadores vivos, correlacionando estes marcadores com episódios de rejeição aguda, eventos infecciosos no pós-transplante, perda do enxerto e óbito do paciente transplantado. E, avaliar a correlação destes marcadores com a sobrevida do enxerto renal nestes períodos. Os pacientes estudados foram transplantados renais com doadores vivos no Hospital Federal de Bonsucesso (HFB) do Rio de Janeiro no ano de 2006 e do período de agosto de 2010 a maio de 2011, sendo uma extensão de um trabalho realizado previamente. CD30s e PRA foram analisados nas amostras coletadas no pré-transplante e com 7, 14, 21 dias, 1, 3, 6, 12 meses após o transplante e nos pacientes transplantados em 2006 amostras após 6 anos de transplante. A taxa de filtração glomerular (TFG) foi estimada utilizando MDRD e CKD-epi e 6 meses, 1 ano e 6 anos após o transplante. Os pacientes foram agrupados em 5 grupos: sem eventos, com perda do enxerto, óbito, rejeição aguda e pacientes com quadros infecciosos. Estes grupos foram avaliados com relação ao CD30s, PRA I e II e comparados dois a dois. O teste qui quadrado foi utilizado. Quando necessário aplicou-se a correção de Yates, o teste de Fisher, o teste de Kruskal-wallis. Foi considerado estatisticamente significante p<0,05. As análises foram feitas pelo programa EPI-Info (versão 3.5.3). Setenta e seis pacientes com doadores vivos foram incluídos no estudo 47 pacientes não tiveram nenhum evento (grupo 1), 7 pacientes perderam o enxerto (grupo 2), 3 pacientes faleceram (grupo 3), 11 pacientes ficaram no grupo de rejeição aguda (grupo 4) e oito pacientes tiveram infecção por CMV e herpes (grupo 5). Os pacientes do grupo de RA tiveram correlação positiva com os valores tanto de CD30s Pré-transplante (p=0,01), quanto do CD30s pós-transplante (p=0,002) e PRA I e II (p<0,001), respectivamente, quando comparados com pacientes sem eventos. A TFG tanto com MDRD e CKD-Epi não mostrou correlação com CD30s pré e pós-transplante e nem PRA I e II. A TFG com as duas fórmulas foi menor no grupo com RA comparado com o grupo sem evento após 6 anos de transplante (p=0,006). CD30s é um bom preditor de RA, assim como PRAI e II. E, também mais uma ferramenta que pode ser utilizada no acompanhamento pós-transplante Renal. A RA é um preditor isolado para diminuição de TFG no transplante.

Le lymphome cutané primitif (LCP) CD30+ est une lymphoprolifération maligne de phénotype T. Son oncogenèse reste à ce jour inconnue. Le but de ma thèse est d'identifier des gènes exprimés spécifiquement dans les LCP CD30+ afin de comprendre les mécanismes d'oncogenèse et également d'identifier des marqueurs diagnostics ou thérapeutiques. Des banques d'ADNc soustraites sont réalisées par SSH « Suppressive Subtractive Hybridisation » entre des LCP CD30+ et des lymphocytes sanguins. Ces banques sont ensuite criblées par des techniques de Dot Blot avec des sondes radiomarquées spécifiques des échantillons étudiés. Les clones sélectionnés sont enfin validés par PCR en temps réel. Nous avons ainsi mis en évidence cinq gènes surexprimés dans les LCP CD30+ : THW, p120caténine, SPARC, PTTG1, CD30 et cinq gènes sousexprimés : humanine, CIN85, Bcl11B, CD30 L et CD30s. Il reste à vérifier si ces gènes sont responsables de l'oncogenèse ou s'ils sont uniquement des phénotypes des LCP CD30+.

<p>Mast cell (MC) accumulation around tumours is an old observation gaining new relevance due to the multifaceted nature of MCs and their many roles in immunity, beyond allergy. Knowledge about tumour specific recruitment of, and interactions with, MCs is needed to unravel the function of their presence.</p><p>This study investigates the participation of mast cells in the tumourigenesis of Hodgkin lymphoma (HL), a tumour with many inflammatory features. We report that MC recruitment into HL lymphomatous tissue is possibly due to the production of CCL5/RANTES by malignant Hodgkin and Reed-Sternberg (HRS) cells. In addition, increased levels of IL-9, a cytokine implicated in mast cell heterogeneity and as an autocrine growth factor for HRS cells, were found in HL patient sera and correlate with negative prognostic factors. The ubiquitous expression of CD30 by HRS cells has been implicated in HL tumour development. In HL tissue MCs were found to be the predominant CD30 ligand (CD30L) expressing cells, and through CD30L/CD30 engagement they induced a proliferative response in HRS cells. This interaction proved to be bi-directional as it induced a degranulation-independent <i>de novo</i> synthesis of a specific set of chemokines in MCs, including IL-8. This novel trigger of MC activation is suggested to be of importance also in atopic dermatitis (AD) and psoriasis since increased numbers of CD30L and IL-8 positive MCs were detected along with increased expression of CD30.</p><p>Data presented in this study supports a specific recruitment of MCs into HL tumours and co-operative interactions between HRS cells and MCs. Our identification of reversed signalling via CD30L as a novel MC trigger provides a mechanism behind leukocyte infiltration and chronic development in diseases associated with CD30 and MCs, such as HL, AD and psoriasis.</p>