Sia nei tumori solidi che nelle neoplasie ematologiche, è stato dimostrato che alcuni agenti chemioterapici, come le antracicline, sono altamente immunogenici e determinano, attraverso le cellule dendritiche (DCs), un’efficiente attivazione della risposta antitumorale mediata dalle cellule T. Tale processo, caratterizzato dalla traslocazione della calreticulina e delle HSPs 70/90 sulla superficie cellulare delle cellule tumorali e dal rilascio di HMGB1 e di ATP, è detto morte cellulare immunogenica (ICD). Oltra alla ICD, però, la chemioterapia genera fenomeni infiammatori nel microambiente tumorale e attiva pathway immunosoppressivi a carico delle DCs, che potrebbero alterare la risposta immunitaria. Scopo del presente studio è stato caratterizzare la ICD indotta da antracicline nella leucemia acuta mieloide (LAM) e valutare l’induzione di pathway inibitori, come l’enzima indoleamina-2,3-diossigenasi (IDO1). In vitro, ex vivo ed in vivo abbiamo dimostrato che il trattamento con antracicline induce ICD anche nella LAM. Nei pazienti sottoposti a chemioterapia è stata riscontrata una risposta anti-leucemica caratterizzata dalla produzione di IFN- nei linfociti CD4+ e CD8+, capaci di uccidere i blasti autologhi pur mostrando un fenotipo exhausted, ma anche l’espansione di una popolazione di linfociti T regolatori. La ICD infatti determina la maturazione delle DCs, che attivano efficacemente linfociti T antigene-specifici ma, allo stesso tempo, esprimendo elevati livelli di IDO1, inducono linfociti T regolatori che limitano la risposta anti-leucemica. Questi risultati sono stati confermati nel modello murino leucemico dove, a seguito della chemioterapia, l’infiltrato tumorale è arricchito di DCs, mature esprimenti IDO1, ma anche di linfociti T caratterizzati da fenotipo exhausted. I nostri dati confermano che la ICD, attiva anche nella LAM, determina una risposta immunitaria efficace nei confronti della malattia ma anche l’attivazione di pathway inibitori nelle DCs che alterano tale risposta. La combinazione della chemioterapia con inibitori di IDO1 rappresenterebbe un approccio interessante per potenziare l'effetto immunogenico della chemioterapia e la risposta anti-leucemica. / Recently, both in solid tumors and haematological malignancies, it has been shown that some chemotherapeutic agents, such as daunorubicin, are highly immunogenic and activate the immune response via cross-priming of anti-tumor T cells by dendritic cells (DCs). Such process, known as immunogenic cell death (ICD), is characterized by tumor cells modifications, such as cell surface translocation of calreticulin and heat shock proteins, extracellular release of ATP and pro-inflammatory factor HMGB1. Alongside with ICD, chemotherapy is known to induce inflammatory modifications within tumor microenvironment, which may also elicit immunosuppressive pathways. In particular, DCs may be driven to acquire tolerogenic features, which may ultimately hamper anti-tumor T-cells. Aim of this study is to characterize ICD in acute myeloid leukemia (AML) and to evaluate the involvement of some DC-related inhibitory pathways, such as indoleamine-2,3-dioxygenase 1 (IDO1) expression. In vitro, ex vivo and in vivo we demonstrated that daunorubicin treatment induced ICD in AML. Ex vivo, T-cell monitoring of daunorubicin-treated AML patients displayed an increase in leukemia-specific IFN--producing CD4+ and CD8+ T cells, which were capable to kill autologous blasts but showed an exhausted phenotype. We also observed the expansion of regulatory T cells (Tregs). ICD, in fact, induced maturation of DCs which efficiently activate antigen-specific T lymphocytes but simultaneously express high levels of IDO1, inducing a population of Tregs which inhibit the anti-leukemia response. These results were confirmed in leukemic murine model where daunorubicin treatment resulted in increased maturation status of tumor infiltrating DCs expressing IDO1, but also in an increased infiltration of exhausted T lymphocytes. Our data confirm that ICD is active in AML and results in an immunological response against AML but also in the induction of inhibitory pathway. The combination of chemotherapy with IDO1 inhibitors represents an interesting approach to enhance the immunogenic effect of chemotherapy and anti-leukemic immune response.

The present work reports the outcome of the GIMEMA CML WP study CML0811, an independent trial investigating nilotinib as front-line treatment in chronic phase chronic myeloid leukemia (CML). Moreover, the results of the proteomic analysis of the CD34+ cells collected at CML diagnosis, compared to the counterpart from healthy donors, are reported. Our study confirmed that nilotinib is highly effective in the prevention of the progression to accelerated/blast phase, a condition that today is still associated with high mortality rates. Despite the relatively short follow-up, cardiovascular issues, particularly atherosclerotic adverse events (AE), have emerged, and the frequency of these AEs may counterbalance the anti-leukemic efficacy. The deep molecular response rates in our study compare favorably to those obtained with imatinib, in historic cohorts, and confirm the findings of the Company-sponsored ENESTnd study. Considering the increasing rates of deep MR over time we observed, a significant proportion of patients will be candidate to treatment discontinuation in the next years, with higher probability of remaining disease-free in the long term. The presence of the additional and complex changes we found at the proteomic level in CML CD34+ cells should be taken into account for the investigation on novel targeted therapies, aimed at the eradication of the disease.

Solid organ transplantation (SOT) is considered the treatment of choice for many end-stage organ diseases. Thus far, short term results are excellent, with patient survival rates greater than 90% one year post-surgery, but there are several problems with the long term acceptance and use of immunosuppressive drugs. Hematopoietic Stem Cells Transplantation (HSCT) concerns the infusion of haematopoietic stem cells to re-establish acquired and congenital disorders of the hematopoietic system. The main side effect is the Graft versus Host Disease (GvHD) where donor T cells can cause pathology involving the damage of host tissues. Patients undergoing acute or chronic GvHD receive immunosuppressive regimen that is responsible for several side effects. The use of immunosuppressive drugs in the setting of SOT and GvHD has markedly reduced the incidence of acute rejection and the tissue damage in GvHD however, the numerous adverse side effects observed boost the development of alternative strategies to improve the long-term outcome. To this effect, the use of CD4+CD25+FOXP3+ regulatory T cells (Treg) as a cellular therapy is an attractive approach for autoimmunity disease, GvHD and limiting immune responses to allograft after transplantation. Treg have a pivotal role in maintaining peripheral immunological tolerance, by preventing autoimmunity and chronic inflammation. Results of my thesis provide the characterization and cell processing of Tregs from healthy controls and patients in waiting list for liver transplantation, followed by the development of an efficient expansion-protocol and the investigation of the impact of the main immunosuppressive drugs on viability, proliferative capacity and function of expanded cells after expansion. The conclusion is that ex vivo expansion is necessary to infuse a high Treg dose and although many other factors in vivo can contribute to the success of Treg therapy, the infusion of Tregs during the administration of the highest dose of immunosuppressants should be carefully considered.

Due to inadequate treatments, the survival rate of adult patients with acute lymphoblastic leukemia (ALL) is still very poor. Thus there is a need to improve the efficacy of conventional therapy. In this study we evaluated the effectiveness of checkpoint kinase inhibitors (Chk-i) in single agent and in combination with different compounds conventionally used for the treatment of B-/T-ALL. We showed that Chk1 and Chk2 kinases are highly expressed and hyper-activated in tumor samples in comparison to normal tissue. On these bases we speculate that the inhibition of these kinases could mine the genetic stability and enhance cell death in ALL cells. We firstly evaluate the efficacy in single agent of the Chk1/Chk2 (PF-0477736 and LY2606368) and of the Wee1 (MK-1775) inhibitors on different cell lines and on primary cells isolated from adult B-ALL patients. We demonstrated that the inhibition of Chk1/Chk2 kinases reduces of the cell viability, activates the apoptosis and modify the expression of different elements of the G2/M checkpoint. To assess the chemo-sensitizer activity of different checkpoint kinase inhibitors, several combination studies were performed. To this purpose, LY2606368 and MK-1775 were combined with different tyrosine kinase inhibitors (imatinb, dasatinib and bosutinib) and with the purine nucleoside analogue, clofarabine. The efficacy of the combinations was not only evaluated in term of reduction of the cell viability but also in term of induction of apoptosis and induction of DNA damages. The results found were then confirmed on primary cells of B-ALL patients. Finally different class of checkpoint kinase inhibitors were combined together in order to evaluate their interaction. In our opinion the preclinical data presented in this study are the basis for a future evaluation of this class of compound in clinical trials in the treatment of adult ALL patients.

Orientador: César Tadeu Spadella / Banca: Juang Horng Jyh / Banca: José Francisco Comenalli Marques Júnior / Banca: Silvana Andréa Molina Lima / Banca: Maria José dos Reis Lima / Resumo: A transfusão sanguínea é um processo que mesmo realizado dentro das normas preconizadas, bem indicado e corretamente administrado, envolve risco para os seus usuários. Este estudo foi realizado com o objetivo de conhecer a incidência de incidentes transfusionais imediatos (ITI) em pacientes internados no HC-Unesp Botucatu, investigar o perfil e a causa das ocorrências, e propor melhorias do processo hemoterápico neste hospital, visando a reduzir os riscos e a recorrência dos eventos. Foram pesquisados e analisados todos os ITI ocorridos em pacientes internados nas unidades hospitalares do HC-Unesp Botucatu, no período retrospectivo de março de 2002 a dezembro de 2006, e no período prospectivo de janeiro de 2007 a dezembro de 2007, tendo sido utilizados o banco de notificações de incidentes transfusionais do Projeto Hospitais Sentinela da Anvisa (PHS-Anvisa), em Botucatu - SP, a revisão dos prontuários dos pacientes e a busca ativa de incidentes nas unidades hospitalares. A investigação das causas dos ITI foi baseada na Ficha de Notificação e Investigação de Incidentes Transfusionais da Anvisa (FIT) e na Ficha para Visita de Hemovigilância do PHS-Anvisa, tendo sido analisadas as seguintes variáveis: nº total de ITI ocorridos nos períodos/nº de transfusões realizadas; nº de ITI identificados por busca ativa e por notificação espontânea da comunidade hospitalar; taxa de subnotificações de incidentes; perfil epidemiológico dos pacientes acometidos por ITI, segundo idade, sexo, diagnóstico de entrada e unidade hospitalar de origem; tipo e gravidade do ITI; manifestações clínicas apresentadas pelos pacientes; distribuição dos ITI por causas de origem dos eventos, segundo causas orgânicas, imunológicas ou ocasionadas por falhas humanas, de processos e/ou de infraestrutura do serviço. Nos períodos, retrospectivo e prospectivo do estudo, foram observados... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Blood transfusion is a process that involves risks to users even when performed according to recommended standards, well indicated and correctly administered. This study was performed with the purpose to learn about the incidence of immediate transfusion incidents (ITI) in inpatients at the University Hospital - Unesp Botucatu, investigate the profile and causes of occurrences and propose improvements for the hemotherapeutic process in that hospital. All ITIs occurring to inpatients at the hospitalization units of the University Hospital - Unesp Botucatu were studied and analyzed in the retrospective period from March 2002 to December 2006 and in the prospective period from January 2007 to December 2007. For data collection, the following sources were used: the database for transfusion incident reports of the Sentinel Hospitals Project of Anvisa (PHS-Anvisa) in Botucatu - SP, a review of patients' medical charts and an active search of incidents at the hospital units. Investigation on ITI causes was based on Anvisa's Transfusion Incident Investigation and Report Form (FIT) and on the Hemosurveillance Visitation Form of PHS-Anvisa, and the following variables were analyzed: total number of ITIs occurring in the periods/number of transfusions performed; number of ITIs identified by means of active search and spontaneous reporting by the hospital community; incident under-reporting rate; epidemiological profile of patients affected by ITI according to age, gender, diagnosis at hospital admission and hospital unit of origin; ITI type and severity; clinical manifestations shown by patients; ITI distribution of causes originating the events according to organic, immunologic causes or those due to human, process and/or service infrastructure failure. In the retrospective and prospective periods of the study, 238 ITIs (168 and 70 incidents, respectively) were observed among... (Complete abstract click electronic access below) / Doutor

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La letteratura scientifica degli ultimi anni si è arricchita di un numero sempre crescente di studi volti a chiarire i meccanismi che presiedono ai processi di homing di cellule staminali emopoietiche e del loro attecchimento a lungo termine nel midollo osseo. Tali fenomeni sembrano coinvolgere da un lato, l’interazione delle cellule staminali emopoietiche con la complessa architettura e componente cellulare midollare, e dall’altro la riposta ad un’ampia gamma di molecole regolatrici, tra le quali chemochine, citochine, molecole di adesione, enzimi proteolitici e mediatori non peptidici. Fanno parte di quest’ultimo gruppo anche i nucleotidi extracellulari, un gruppo di molecole-segnale recentemente caratterizzate come mediatori di numerose risposte biologiche, tra le quali l’allestimento di fenomeni flogistici e chemiotattici. Nel presente studio è stata investigata la capacità dei nucleotidi extracellulari ATP ed UTP di promuovere, in associazione alla chemochina CXCL12, la migrazione di cellule staminali umane CD34+. E’ così emerso che la stimolazione con UTP è in grado di incrementare significativamente la migrazione dei progenitori emopoietici in risposta al gradiente chemioattrattivo di CXCL12, nonché la loro capacità adesiva. Le analisi citofluorimetriche condotte su cellule migranti sembrano inoltre suggerire che l’UTP agisca interferendo con le dinamiche di internalizzazione del recettore CXCR4, rendendo così le cellule CD34+ maggiormente responsive, e per tempi più lunghi, al gradiente attrattivo del CXCL12. Saggi di homing competitivo in vivo hanno parallelamente mostrato, in topi NOD/SCID, che la stimolazione con UTP aumenta significativamente la capacità dei progenitori emopoeitci umani di localizzarsi a livello midollare. Sono state inoltre indagate alcune possibili vie di trasduzione del segnale attivate dalla stimolazione di recettori P2Y con UTP. Esperimenti di inibizione in presenza della tossina della Pertosse hanno evidenziato il coinvolgimento di proteine Gαi nella migrazione dipendente da CXCL12 ed UTP. Ulteriori indicazioni sono provenute dall’analisi del profilo trascrizionale di cellule staminali CD34+ stimolate con UTP, con CXCL12 o con entrambi i fattori contemporaneamente. Da questa analisi è emerso il ruolo di proteine della famiglia delle Rho GTPasi e di loro effettori a valle (ROCK 1 e ROCK 2) nel promuovere la migrazione UTP-dipendente. Questi dati sono stati confermati successivamente in vitro mediante esperimenti con Tossina B di C. Difficile (un inibitore delle Rho GTPasi) e con Y27632 (in grado di inibire specificatamente le cinasi ROCK). Nel complesso, i dati emersi in questo studio dimostrano la capacità del nucleotide extracellulare UTP di modulare la migrazione in vitro di progenitori emopoietici umani, nonché il loro homing midollare in vivo. L’effetto dell’UTP su questi fenomeni si esplica in concerto con la chemochina CXCL12, attraverso l’attivazione concertata di vie di trasduzione del segnale almeno parzialmente condivise da CXCR4 e recettori P2Y e attraverso il reclutamento comune di proteine ad attività GTPasica, tra le quali le proteine Gαi e i membri della famiglia delle Rho GTPasi.

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