Perfil dos linfócitos T reguladores e efetores em pacientes com linfoma de Hodgkin clássico
Data
2014
Autores
Penna, Adriana Marques Damasco 
Orientadores
Baiocchi, Otavio Carvalho Guimarães
Tipo
Tese de doutorado
Título da Revista
ISSN da Revista
Título de Volume
Resumo
O linfoma de Hodgkin classico (LHc) e a neoplasia linfoide mais comum em adultos jovens. Trata-se de doenca curavel em 75% dos casos, porem 25% dos pacientes vao apresentar doenca refrataria ou recidivada com pior evolucao. Diferente de todas as neoplasias humanas, as celulas malignas do LHc, denominadas Reed-Sternberg (RS), compoe 1 a 5% de toda a massa tumoral, sendo o restante composto por celulas inflamatorias normais. As celulas de RS perpetuam-se em meio a este microambiente devido a incapacidade do sistema imune em reconhece-las e combate-las. Linfocitos T reguladores (LTR) sao moduladores importantes do microambiente em doencas linfoproliferativas e tem a capacidade de limitar a funcao dos linfocitos T efetores (LTE). Ja foi descrito que, no microambiente tumoral, os LTR estao aumentados e os LTE diminuidos. Mas o comportamento destas celulas no sangue periferico de pacientes com neoplasias ainda nao esta bem explicado. Portanto, compreender qual o papel do desequilibrio imunologico no LHc e crucial para o desenvolvimento de novos fatores prognosticos e alvos terapeuticos. Objetivos: Quantificar os LTR e LTE no sangue periferico e microambiente de pacientes com LHc. Correlacionar a presenca dos LTR e LTE no microambiente tumoral com o sangue periferico. Correlacionar a presenca do EBV nas celulas RS com a quantificacao destas subpopulacoes de linfocitos T. Avaliar a importancia da presenca do EBV, dos LTR e LTE na resposta ao tratamento dos pacientes com LHc. Avaliar o impacto do tratamento na quantificacao de linfocitos T reguladores e TH17 de pacientes com LHc. Casuistica e Metodo: Foram recrutados para este estudo, prospectivamente, 60 pacientes diagnosticados com LHc entre marco de 2009 e marco de 2013 em dois servicos de Hematologia distintos da cidade de São Paulo. Foram incluidos, tambem, 19 controles saudaveis recrutados no banco de sangue do Hemocentro da UNIFESP apos serem aprovados para doacao. A quantificacao de LTR e LTE foi avaliada por citometria de fluxo utilizando os anticorpos CD3, CD4, CD25, FOXP3, GITR e IL17 e por imunoistoquimica utilizando o anticorpo FOXP3. Resultados: A quantificacao de celulas T CD4+FOXP3+ e CD4+GITR+ foi maior em pacientes que nos controles (36,92 u 23,5%; p=0,009 e 39,63 - 14,3%; p<0,0001 respectivamente). O tratamento do LHc reduz a quantificacao de linfocitos T CD4+GITR+ (19,44 - 16,8%; p=0,036). A contagem de linfocitos T CD4+FOXP3+, CD4+CD25highFOXP3+ e CD4+IL17+ e maior nos pacientes que nos controles (32,1 u 24,24%; p=0,009, 31,28 u 21,79%; p=0,037, 32,9 - 18,71%; p=0,002 e 33,00 u 18,53; p=0,001, respectivamente). Os pacientes com sintomas B apresentaram quantificacao de linfocitos CD4+FOXP3+ no microambiente maior (p=0,032). Conclusoes: Houve correlacao positiva e significante entre a quantificacao de LTR circulante e no microambiente e o estadiamento avancado da doenca e entre a quantificacao de LTR e LTE circulantes nos pacientes e nos controles. Nao houve correlacao da quantificacao de LTR e LTE no sangue periferico ou no microambiente com a presenca do virus EBV nas celulas de RS ou entre a quantificacao de LTR e LTE em sangue periferico e a quantificacao de LTR no microambiente tumoral dos pacientes estudados. O tratamento quimio e radioterapico diminuiu a quantificacao de LTR e LTE circulantes.
Introduction: Classical Hodgkin Lymphoma is the most commom form of malignant lymphoma in young adults. This malignancy is curable in 75% of the patients. However 25% of individuals with this disease relapse after initial treatment. Classical HL is unique amongst lymphoid cancers in that the malignant cells, the so called Hodgkin ReedSternberg (HRS) cells, make up only 15% of the tumor. Although scarce, the HRS cells appear to orchestrate an extensive tumor microenvironment, permitting the tumor cells to attain the full malignant phenotype and evade immune surveillance Regulatory T lymphocyte are important modulators of the microenvironment of malignant lymphomas and are able to scant the function of effector T lymphocytes. Some authors have described the malignant microenvironment to be rich in Tregs and depleted of T effector cells. Still, the knowledge of the behavior of these cells in peripheral blood of patients with cancer is not well documented. Therefore, understanding the role of the immune unbalance in cHL is crucial to identify reliable biomarkers and novel therapeutic targets. Aims: Quantify Tregs and effector T lymphocytes in peripheral blood and in the microenvironment of cHL patients. Verify if there is association between the quantification of Tregs, effector T cells and EBV in the RS cells with the outcome of these patients. Methods: We enrolled 60 patients with cHL for this study between 2009 and 2013 and 19 healthy controls. Treg and effector T cells were evaluated with flow citometry and immunohistochemistry using CD3, CD4, CD25, FOXP3, GITR and Il17. Results: Treg and effector T lymphocyte count were higher in samples from patients than controls (p=0,009 e p<0,001 respectively). Treatment reduces the frequency of CD4+GITR+ lymphocytes (p=0,0036). CD4+FOXP3+, CD4+CD25highFOXP3+ and CD4+IL17+ frequencies were higher in the patients than in the control group (p=0,009; p=0,0037; p=0,002 and p=0,001 respectively). There was no association between Treg and effector T cells in peripheral blood and in the microenvironment. Conclusions: We could show a positive correlation between frequency of Tregs in the microenvironment and in peripheral blood with advanced stage disease and between patients and controls in peripheral blood. There was no correlation between the frequency of this cells and the presence of EBV in RS cells. Treatment reduces the frequency of Treg and effector T cells.
Introduction: Classical Hodgkin Lymphoma is the most commom form of malignant lymphoma in young adults. This malignancy is curable in 75% of the patients. However 25% of individuals with this disease relapse after initial treatment. Classical HL is unique amongst lymphoid cancers in that the malignant cells, the so called Hodgkin ReedSternberg (HRS) cells, make up only 15% of the tumor. Although scarce, the HRS cells appear to orchestrate an extensive tumor microenvironment, permitting the tumor cells to attain the full malignant phenotype and evade immune surveillance Regulatory T lymphocyte are important modulators of the microenvironment of malignant lymphomas and are able to scant the function of effector T lymphocytes. Some authors have described the malignant microenvironment to be rich in Tregs and depleted of T effector cells. Still, the knowledge of the behavior of these cells in peripheral blood of patients with cancer is not well documented. Therefore, understanding the role of the immune unbalance in cHL is crucial to identify reliable biomarkers and novel therapeutic targets. Aims: Quantify Tregs and effector T lymphocytes in peripheral blood and in the microenvironment of cHL patients. Verify if there is association between the quantification of Tregs, effector T cells and EBV in the RS cells with the outcome of these patients. Methods: We enrolled 60 patients with cHL for this study between 2009 and 2013 and 19 healthy controls. Treg and effector T cells were evaluated with flow citometry and immunohistochemistry using CD3, CD4, CD25, FOXP3, GITR and Il17. Results: Treg and effector T lymphocyte count were higher in samples from patients than controls (p=0,009 e p<0,001 respectively). Treatment reduces the frequency of CD4+GITR+ lymphocytes (p=0,0036). CD4+FOXP3+, CD4+CD25highFOXP3+ and CD4+IL17+ frequencies were higher in the patients than in the control group (p=0,009; p=0,0037; p=0,002 and p=0,001 respectively). There was no association between Treg and effector T cells in peripheral blood and in the microenvironment. Conclusions: We could show a positive correlation between frequency of Tregs in the microenvironment and in peripheral blood with advanced stage disease and between patients and controls in peripheral blood. There was no correlation between the frequency of this cells and the presence of EBV in RS cells. Treatment reduces the frequency of Treg and effector T cells.
Descrição
Citação
PENNA, Adriana Marques Damasco. Perfil dos linfócitos T reguladores e efetores em pacientes com linfoma de Hodgkin. 2014. 114 f. Tese (Doutorado em Ciências) – Escola Paulista de de Medicina, Universidade Federal de São Paulo. São Paulo, 2014.