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2.
Minerva Anestesiol ; 77(5): 522-7, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21540807

RESUMO

AIM: HLA-DR monocyte expression may be affected by major surgery. A potential mechanism for monocyte activation is the engagement of costimulatory receptors (B7-2 or CD-86). The aim of the present study was to determine the possible role of monocyte HLA-DR and B7-2 molecules in the occurrence of postoperative sepsis after major cancer surgery. METHODS: This was an observational study in 25 consecutive patients undergoing major elective surgery. Flow cytometry measures were used to determine the expression of HLA-DR and its costimulatory receptors before (day 0) and after surgery (day 1 and day 2). RESULTS: After surgery, the rate of monocytes expressing HLA-DR decreased significantly in all the patients. As compared with day 0, the rate of monocytes expressing B7-2 decreased in all the patients (P<0.03). In the septic group, it remained significantly decreased postoperatively. In the non-septic group, it reached baseline levels at day 2. CONCLUSION: Results suggest a key role for costimulatory molecules in modulating inflammatory response in the context of subsequent postoperative sepsis after major cancer surgery. These molecules may be involved, in association with HLA-DR, in postoperative monocyte dysfunction.


Assuntos
Antígeno B7-2/biossíntese , Antígenos HLA-DR/biossíntese , Monócitos/metabolismo , Neoplasias/cirurgia , Sepse/imunologia , Adulto , Idoso , Procedimentos Cirúrgicos Eletivos , Feminino , Citometria de Fluxo , Humanos , Terapia de Imunossupressão , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/imunologia , Período Pós-Operatório , Sepse/metabolismo
3.
Leukemia ; 23(2): 350-7, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18987664

RESUMO

An early appreciation of treatment efficacy could be very useful in acute myeloblastic leukemia (AML), and a prognostic value has been suggested for the morphological assessment of decrease in blasts during induction therapy. More sensitive, multiparametric flow cytometry (FCM) can detect far lower blast counts, allowing for a precise and reliable calculation of blast cell decrease rate (BDR). Such a multiparametric FCM four-colours/single-tube protocol, combining CD11b, CD45-ECD and CD16-PC5, was applied to peripheral blood samples from 130 AML patients, collected daily during induction chemotherapy. Normalized blast cell percentages were used to calculate the relevant decrease slopes. Slope thresholds (<-25, -25 to -15 and >-15), or the time required to reach 90% depletion of the peripheral blast load (<5, 5 or >5 days), was strongly associated with the achievement of complete remission (P<0.0001). Log-rank test and Cox model showed that they also carried high statistical significance (P<0.0001) for disease-free survival. The prognostic value of cytogenetic features, confirmed in this series, was refined by BDR, which allowed to discriminate between good- and poor-risk patients among those with intermediate or normal karyotypes. This simple FCM protocol allows for an accurate prognostic sequential approach adapted to the determination of decrease in peripheral blast cells during induction chemotherapy.


Assuntos
Crise Blástica/patologia , Citometria de Fluxo/métodos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Contagem de Células , Feminino , Humanos , Imunofenotipagem , Cariotipagem , Masculino , Pessoa de Meia-Idade , Prognóstico , Indução de Remissão , Adulto Jovem
4.
Rev Med Interne ; 29(5): 424-35, 2008 May.
Artigo em Francês | MEDLINE | ID: mdl-18359538

RESUMO

INTRODUCTION: Chronic lymphocytic leukemia (CLL) is the most common leukaemia in the Western world. Recent advancement in the aetiology, pathophysiology and the development of new therapeutics tools have significantly modified the current management of CLL. CURRENT KNOWLEDGE AND KEY POINTS: The cellular origin of CLL is still unknown. The current main hypothesis will be first briefly described. This review will then focus on the newly defined prognostic factors and the development and use of new drugs for the treatment of CLL. To describe the modern and practical management of CLL, we will compare classical and new prognostic markers. Then, we will discuss the various therapeutic options including chemotherapy and immunotherapy (monoclonal antibodies, allogenic transplantation), and define their current respective indications. FUTURE PROSPECTS AND PROJECTS: These new diagnostic and prognostic markers will allow the characterization of new prognostic subgroups of patients. This will lead to a targeted and individualized therapeutic approach. We will present the first results of clinical trials and the on-going studies conducted in this disease.


Assuntos
Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Antineoplásicos/uso terapêutico , Humanos , Incidência , Leucemia Linfocítica Crônica de Células B/epidemiologia , Leucemia Linfocítica Crônica de Células B/mortalidade , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco , Análise de Sobrevida
5.
Bone Marrow Transplant ; 36(10): 901-6, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16151421

RESUMO

The use of recombinant human erythropoietin (rHuEPO) has been controversial after myeloablative allogeneic Stem cell transplantation (allo-SCT). Reduced intensity conditioning regimens (RIC) offer a novel approach that might translate into a different profile of erythropoietic recovery. We treated 20 consecutive patients with rHuEPO early after matched sibling RIC allo-SCT. Conditioning included fludarabine, busulfan and antithymocyte globulin. EPO treatment was analyzed in terms of toxicity, impact on the frequency of Red blood cell transfusions (RBCT) and kinetics of Hemoglobin recovery within the 60 days post-allo-SCT. Results were compared with 27 matched patients who did not receive rHuEPO. In the first 2 months after allo-SCT all patients receiving rHuEPO (100%) achieved an Hb level > 11 g/dl at a median of 30 (15-35) days post-allo-SCT, as compared to only 63% of the patients not receiving rHuEPO (P = 0.007) at a median of 35 (20-55) days (P = 0.03). A total of 70% (95% CI, 50-90) of rHuEPO patients maintained an Hb over 11 g/dl in the second month as compared to only 19% (95% CI, 4-34) in the other group (P = 0.0004). For patients receiving RBCT, the use of rHuEPO was associated with a trend towards reduced RBCT requirements. This pilot study suggests a potential benefit of early administration of rHuEPO after RIC allo-SCT on early erythropoietic recovery.


Assuntos
Eritropoetina/administração & dosagem , Transplante de Células-Tronco Hematopoéticas/métodos , Hemoglobinas/efeitos dos fármacos , Condicionamento Pré-Transplante/métodos , Adulto , Idoso , Eritropoese/efeitos dos fármacos , Eritropoetina/toxicidade , Feminino , Neoplasias Hematológicas/terapia , Hemoglobinas/análise , Humanos , Masculino , Pessoa de Meia-Idade , Agonistas Mieloablativos/uso terapêutico , Projetos Piloto , Proteínas Recombinantes , Transplante Homólogo
6.
Transfusion ; 44(4): 501-8, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15043564

RESUMO

BACKGROUND: RBCT (RBCT) requirements of stem cell transplant (SCT) recipients are often substantial and may be related to transplant type. STUDY DESIGN AND METHODS: An analysis was done of RBCT requirements and Hb recovery kinetic in the first 60 days after HLA-identical sibling allogeneic SCT in a series of 110 consecutive patients treated for various malignant diagnoses. Patients were prepared with either an antithymocyte globulin (ATG) and reduced intensity chemotherapy-based conditioning (RIC) (n=64) or a myeloablative conditioning regimens (MAC; n=46). Patients received marrow (n=64) or PBPCs (n=46). RESULTS: Overall, intensity of conditioning regimen (RIC vs. MAC; p=0.0005) and graft source (PBPC vs. marrow; p<0.0001) independently predicted RBCT requirements. Hb recovery was accelerated after RIC when compared to MAC allo-SCT (p=0.02). In RIC patients, RBCTs were inversely correlated to Hb level before conditioning (p<0.0001) and the dose of ATG (p=0.009). Moreover, Hb level before allo-SCT significantly influenced Hb recovery kinetic after RIC but had no impact on RBCT requirements and Hb recovery after MAC. CONCLUSION: Thus, RIC conditioning creates a different pattern of erythropoiesis recovery as compared to a MAC regimen and suggest a need for studies aimed at further reducing RBCT and accelerating Hb recovery.


Assuntos
Antineoplásicos/farmacologia , Transfusão de Eritrócitos/estatística & dados numéricos , Eritropoese/efeitos dos fármacos , Transplante de Células-Tronco Hematopoéticas/métodos , Condicionamento Pré-Transplante/métodos , Adolescente , Adulto , Idoso , Antineoplásicos/uso terapêutico , Transplante de Medula Óssea/efeitos adversos , Feminino , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Hemoglobinas/análise , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Transplante de Células-Tronco de Sangue Periférico/efeitos adversos , Valor Preditivo dos Testes , Prognóstico , Transplante Homólogo
7.
Bone Marrow Transplant ; 32(11): 1059-64, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14625576

RESUMO

The purpose of this study was to evaluate the presence of micrometastatic cells in the apheresis products from patients with breast cancer, and also to determine if repeated infusion of contaminated products had any clinical impact. A total of 94 patients with high-risk breast cancer were enrolled in a prospective single center study to evaluate the use of dose-intensified chemotherapy (doxorubicine 75 mg/m(2) and cyclophosphamide 3000 or 6000 mg/m(2) for four cycles) with repeated (x 2) stem cell reinfusion. All women were monitored for the presence of metastatic cells in aphereses, collected after first course of intensive chemotherapy, and following additional mobilization with rhG-CSF. Epithelial cells were screened with monoclonal antibodies directed to cytokeratin. Eight of the 94 patients had detectable tumor cells in one or several aphereses collected after intensive chemotherapy; this was unrelated to other tumor characteristics, including size, histology, Scarff Bloom and Richardson (SBR) grading (presence or absence of hormone receptors). Hemato-poietic reconstitution was similar in the cells from these eight patients, and in the total patient population. Three of these eight patients relapsed. This study has confirmed that contamination of apheresis products remains a rare event, which does not seem to affect clinical evolution, even when reinfused into the patient.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Remoção de Componentes Sanguíneos/efeitos adversos , Neoplasias da Mama/terapia , Células Neoplásicas Circulantes/patologia , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidade , Remoção de Componentes Sanguíneos/normas , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Contagem de Células , Ciclofosfamida/administração & dosagem , Relação Dose-Resposta a Droga , Doxorrubicina/administração & dosagem , Feminino , Mobilização de Células-Tronco Hematopoéticas , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/normas , Humanos , Pessoa de Meia-Idade , Metástase Neoplásica/patologia , Estudos Prospectivos , Análise de Sobrevida , Resultado do Tratamento
8.
Leukemia ; 16(10): 2129-33, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12357367

RESUMO

Large granular lymphocyte (LGL) proliferation typically follows a chronic course during which major features are cytopenia and immune abnormalities. Elevated numbers of LGL were reported in a few cases following allogeneic stem cell transplantation (allo-SCT). In this report, we present a retrospective analysis of LGL cases that occurred following allo-SCT in a cohort of 201 consecutive patients transplanted over a period of 7 years. Six cases were identified and LGL expansion occurred more frequently following a reduced fludarabine and anti-T lymphocyte globulin-based preparative regimen (4 cases/49), than after a conventional myeloablative regimen (2 cases/152). Expansion of LGL was seen between 3 and 15 months following allo-SCT. Hematopoiesis, with mild to severe cytopenia, was a favored target for LGL. Autoimmune manifestations including polyarthritis and hypergammaglobulinemia were also observed. LGL proliferation was observed in the context of chronic antigenic stimulation associated with recurrent viral infections especially CMV. Moreover, five out of these six high risk patients achieved a long-term complete remission concomitant or following LGL expansion. These data suggest that LGL might be a subset of effector lymphocytes which may participate to the graft-versus-tumor effect.


Assuntos
Divisão Celular , Transplante de Células-Tronco Hematopoéticas , Linfócitos/citologia , Adulto , Feminino , Hematopoese , Humanos , Leucemia/complicações , Leucemia/patologia , Leucemia/terapia , Masculino , Pessoa de Meia-Idade , Condicionamento Pré-Transplante , Transplante Homólogo , Resultado do Tratamento , Viroses/complicações
9.
Hematology ; 7(3): 157-64, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12243978

RESUMO

Approaches using reduced conditioning regimens have been developed to obtain minimal procedure-related toxicity. Such novel therapeutic options are being explored with good preliminary results concerning feasibility and engraftment. However, many aspects remain under-evaluated and few data are available about immune and dendritic cell (DC) reconstitution after these highly immunosuppressive regimens. We present here our data in 20 patients receiving allogeneic bone marrow transplantation (allo-BMT) using a reduced preparative regimen. We evaluated in the first 3 months following allo-BMT, several immunological parameters including DC subsets, and compared these to historical results obtained in a group of myeloablative allo-BMT patients. We found an early recovery of leukocytes, CD8+ and NK lymphocytes. We also found a trend towards an improved B cell recovery. These results are somewhat in contrast to the altered immune recovery observed in the myeloablative setting. In addition, we found a significant early circulating DC recovery. Circulating blood DCs were also found to be of full donor origin as assessed by FISH in sex-mismatched pairs. Nevertheless, naive CD4 + CD45RA + T cells were found to be profoundly reduced following such regimens.Collectively, these data further enhance the overall benefits of reduced intensity regimens and the need for a stringent biological monitoring for assessment of the potential advantages of reduced intensity allo-BMT in comparison with conventional allo-BMT.


Assuntos
Transplante de Medula Óssea/métodos , Células Dendríticas/citologia , Sistema Imunitário/citologia , Subpopulações de Linfócitos/citologia , Condicionamento Pré-Transplante/métodos , Adulto , Linfócitos B/citologia , Células Sanguíneas/citologia , Linfócitos T CD8-Positivos/citologia , Feminino , Sobrevivência de Enxerto , Neoplasias Hematológicas/terapia , Humanos , Sistema Imunitário/crescimento & desenvolvimento , Imunofenotipagem , Células Matadoras Naturais/citologia , Leucócitos/citologia , Masculino , Pessoa de Meia-Idade , Transplante Homólogo , Transplante Isogênico
10.
Leukemia ; 16(5): 855-60, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11986947

RESUMO

We describe a patient with acute myeloid leukemia (AML) who developed polyclonal large granular lymphocyte (LGL) proliferation. The reciprocal evolution of AML and LGLs suggested that these LGLs had an anti-tumor activity. The patient's LGLs killed autologous leukemia cells in a different way to classical T lymphocyte-mediated cytotoxicity since it did not rely on the recognition of target antigens presented by major histocompatibility complex (MHC) class I molecules by the CD3/TcRalphabeta complex. This killing was also different from natural killer (NK)-mediated cytotoxicity, which depends on the absence of MHC class I molecule recognition by NK inhibitory receptors. The LGLs were polyclonal, had a CD3+/CD8+/CD56+ phenotype, and did not express the natural killer cell receptors (NKRs) for MHC class I molecules. The LGLs did not express the NK-specific activating natural cytotoxicity receptors but expressed the 2B4 non-MHC restricted triggering receptor, whose ligand CD48 was expressed by leukemic cells and normal bone marrow cells. The 2B4 receptor participated in the ability of LGLs to lyse patient's leukemia. This represents a novel function for 2B4 in man, since this molecule, at variance with the murine system, was considered not to have direct effects on CD8+ T cell-mediated cytotoxicity. This case report allowed us to describe a novel T lymphocyte-mediated anti-tumor mechanism which relied on (1) the abnormal expansion of the rare 2B4-positive CD3+/CD8+/CD56+ T lymphocyte subset, (2) an as yet undescribed cytotoxicity mechanism in man which depended on 2B4 molecule. The relevance of this observation in human cancer immunotherapy has to be further investigated.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Citotoxicidade Imunológica , Leucemia Mieloide/patologia , Receptores Imunológicos , Doença Aguda , Antígenos CD/metabolismo , Complexo CD3 , Antígeno CD48 , Antígeno CD56 , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/ultraestrutura , Humanos , Imunofenotipagem , Leucemia Mieloide/metabolismo , Ativação Linfocitária/imunologia , Masculino , Glicoproteínas de Membrana/imunologia , Pessoa de Meia-Idade , Proteínas de Neoplasias/metabolismo , Família de Moléculas de Sinalização da Ativação Linfocitária , Subpopulações de Linfócitos T/citologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/ultraestrutura
12.
Clin Lab Haematol ; 23(2): 81-90, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11488846

RESUMO

PNH is a disorder of the pluripotent stem cells resulting in a deficient expression of membrane-bound GPI-anchored proteins in different cell types. Several flow cytometric approaches are designed to detect this antigen deficiency. But they all require drawing and testing of normal samples as control. Therefore, in the present study two flow cytometric assays for the detection of CD55 and CD59 deficiency in erythrocytes (REDQUANT CD55/CD59) and granulocytes (CELLQUANT CD55/CD59) are proposed. Precalibrated beads are used to define the cut off between normal and deficient cell populations. The specificity of the tests has been evaluated in healthy blood donors (n=52) resulting in a clear and reproducible cut off (3%) for the normal percentage of GPI-deficient cells. This cut off has been confirmed in leukaemia and lymphoma patients not suspected for developing PNH. The sensitivity has been tested in patients suffering from known PNH (n=23). Both tests performed in combination allowed a reliable detection of PNH in all patients showing antigen deficiencies in both cell types in most patients (20/23). In contrast, the PNH clones in the investigated patients with MDS (4/19) or AA (4/22) were present in granulocytes or erythrocytes, only. This underlines the necessity of analysing erythrocytes as well as granulocytes. Preliminary data regarding a possible correlation between disease activity and percentage of antigen-deficient cells lead to the assumption that haemolytic crises can only be determined on granulocytes whereas deficient erythrocytes disappeared due to complement-mediated lysis of the PNH clone. In conclusion, the combination of the test kits enables the differential diagnosis of PNH clones in a standardized, simple and rapid approach which may have therapeutic consequences.


Assuntos
Antígenos CD55/imunologia , Antígenos CD59/imunologia , Hemoglobinúria Paroxística/imunologia , Eritrócitos/imunologia , Citometria de Fluxo/métodos , Citometria de Fluxo/normas , Granulócitos/imunologia , Hemoglobinúria Paroxística/sangue , Humanos
13.
Br J Haematol ; 113(4): 1047-50, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11442501

RESUMO

True histiocytic lymphoma (THL) is a very rare type of non-Hodgkin's lymphoma (NHL) in which neoplastic cells exhibit markers of histiocytic differentiation. Some cases of THL have been reported in patients with previous acute lymphoblastic leukaemia (ALL), especially in children and young adults, in whom the acute leukaemia was of T-cell origin. The relationship between the initial lymphoid tumour and the secondary THL remains unclear, as a common monoclonal origin shared by both neoplasms has never been definitively demonstrated. We report a patient with B-ALL who developed a nodal and extranodal tumour with histological and immunohistochemical features of THL 4 years after the initial diagnosis. Genotypic study showed that both neoplasms contained the same immunoglobulin heavy gene rearrangement, which has not been reported previously.


Assuntos
Linfoma de Burkitt/complicações , Linfoma de Burkitt/genética , Rearranjo Gênico de Cadeia Pesada de Linfócito B , Linfoma Difuso de Grandes Células B/complicações , Linfoma Difuso de Grandes Células B/genética , Adulto , Antígenos CD/análise , Antígenos de Diferenciação Mielomonocítica/análise , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma de Burkitt/diagnóstico , Ciclofosfamida/administração & dosagem , Dacarbazina/administração & dosagem , Daunorrubicina/administração & dosagem , Humanos , Imuno-Histoquímica , Antígenos Comuns de Leucócito/análise , Linfoma Difuso de Grandes Células B/diagnóstico , Masculino , Reação em Cadeia da Polimerase , Proteínas S100/análise
14.
Acta Haematol ; 105(3): 166-71, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11463991

RESUMO

Breast cancer is the most frequent neoplastic disease in populations of developed countries. It will affect 1 of every 6 or 7 women during their lifetime. The disease eventually evolves to a metastatic stage, and currently appears to be not curable at that stage. Thus, understanding mechanisms that result in the establishment of tumor at sites distant from the primary location is of the utmost importance. Equally important is the definition of a metastatic state, especially in regard to the detection of micrometastases. Finally, the presence of circulating tumor cells in the peripheral blood of patients who undergo progenitor mobilization, collection and reinfusion may be of clinical significance in the setting of high-dose chemotherapy for breast cancer.


Assuntos
Medula Óssea , Neoplasias da Mama/patologia , Células Epiteliais/patologia , Medula Óssea/patologia , Purging da Medula Óssea , Neoplasias da Mama/secundário , Feminino , Transplante de Células-Tronco Hematopoéticas , Humanos , Transplante Autólogo
15.
Bone Marrow Transplant ; 28(12): 1157-60, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11803360

RESUMO

We report here the first case of large granular lymphocytes (LGL) expansion following non-myeloablative allo-BMT for chronic myeloid leukemia. We characterized the morphologic, phenotypic and functional features of the LGL subset amplified in vivo 14 months after allo-BMT. Our results indicate that LGL can mediate in vitro a cytolytic activity on tumor cells. In vivo, the timing of the LGL expansion was associated with a sustained complete molecular remission. These observations suggest that LGL are a subset with the properties of effector lymphocytes which may contribute to the graft-versus-tumor effect.


Assuntos
Transplante de Medula Óssea/efeitos adversos , Efeito Enxerto vs Tumor , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Linfocitose/etiologia , Citotoxicidade Imunológica , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/imunologia , Masculino , Pessoa de Meia-Idade , Subpopulações de Linfócitos T/imunologia , Condicionamento Pré-Transplante , Transplante Homólogo
17.
Cancer Res ; 60(16): 4403-11, 2000 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-10969785

RESUMO

The destruction of cells capable of initiating and maintaining leukemia challenges the treatment of human acute myeloid leukemia. Recently, CD34+/CD38- leukemia progenitors have been defined as new leukemia-initiating cells less mature than colony-forming cells. Here we show that CD34+/CD38- leukemia precursors have reduced in vitro sensitivity to daunorubicin, a major drug used in leukemia treatment, in comparison with the CD34+/CD38+ counterpart, and increased expression of multidrug resistance genes (mrp/lrp). These precursors show lower expression of Fas/Fas-L and Fas-induced apoptosis than CD34+/CD38+ blasts. Moreover, the CD34+/CD38- leukemic subpopulation induces a weaker mixed leukocyte reaction of responding T-lymphocytes than the CD34+/CD38+ leukemic counterpart, either in a MHC-unmatched or MHC-matched settings. This weaker immunogenicity could be linked to lower expression on CD34+/CD38- leukemia precursors of major immune response molecules (MHC-DR, LFA-3, B7-1, or B7-2) than CD34+/CD38+ leukemic cells. Nonetheless, the susceptibility of the immature CD38- precursors to cytotoxicity was not different from the sensitivity of the CD38+ counterpart. Finally, CD34+/CD38- leukemia precursors, in contrast with CD38+ precursors, failed, under appropriate conditions, to differentiate into dendritic cells, a central step for antigen recognition. This is to our knowledge the first demonstration that the very immature phenotype of CD34+/CD38- leukemic progenitors confers both chemotherapy resistance and decreased capacities to induce an immune response. Because the susceptibility of the immature leukemia cells as cytotoxic targets is maintained, our data underline the importance of improving the initial steps of leukemia recognition, more particularly by defining optimal conditions of dendritic cell transformation of the very immature hematopoietic precursors.


Assuntos
Antígenos CD34/imunologia , Antígenos de Diferenciação/imunologia , Apoptose/fisiologia , Células Dendríticas/patologia , Leucemia Mieloide/patologia , NAD+ Nucleosidase/imunologia , Células-Tronco Neoplásicas/imunologia , Receptor fas/fisiologia , ADP-Ribosil Ciclase , ADP-Ribosil Ciclase 1 , Doença Aguda , Antibióticos Antineoplásicos/farmacocinética , Antibióticos Antineoplásicos/farmacologia , Antígenos CD/biossíntese , Apoptose/efeitos dos fármacos , Antígeno B7-1/biossíntese , Antígeno B7-2 , Antígenos CD58/biossíntese , Diferenciação Celular/fisiologia , Daunorrubicina/farmacocinética , Daunorrubicina/farmacologia , Células Dendríticas/imunologia , Resistencia a Medicamentos Antineoplásicos/genética , Proteína Ligante Fas , Expressão Gênica , Antígenos HLA-DR/biossíntese , Células-Tronco Hematopoéticas/imunologia , Humanos , Leucemia Mieloide/imunologia , Leucemia Mieloide/metabolismo , Complexo Principal de Histocompatibilidade/imunologia , Glicoproteínas de Membrana/biossíntese , Glicoproteínas de Membrana/metabolismo , Glicoproteínas de Membrana/fisiologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptor fas/metabolismo
18.
Blood ; 96(4): 1287-96, 2000 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-10942370

RESUMO

Acute promyelocytic leukemia (APL) is typified by the t(15;17) translocation, which leads to the formation of the PML/RARA fusion gene and predicts a beneficial response to retinoids. However, approximately 10% of all APL cases lack the classic t(15;17). This group includes (1) cases with cryptic PML/RARA gene rearrangements and t(5;17) that leads to the NPM/RARA fusion gene, which are retinoid-responsive, and (2) cases with t(11;17)(q23;q21) that are associated with the PLZF/RARA fusion gene, which are retinoid-resistant. A key issue is how to rapidly distinguish subtypes of APL that demand distinct treatment approaches. To address this issue, a European workshop was held in Monza, Italy, during June 1997, and a morphologic, immunophenotypic, cytogenetic, and molecular review was undertaken in 60 cases of APL lacking t(15;17). This process led to the development of a novel morphologic classification system that takes into account the major nuclear and cytoplasmic features of APL. There were no major differences observed in morphology or immunophenotype between cases with the classic t(15;17) and those with the cryptic PML/RARA gene rearrangements. Auer rods were absent in the t(5;17) case expressing NPM/RARA. Interestingly, this classification system distinguished 9 cases with t(11;17)(q23;q21) and, in addition, successfully identified 2 cases lacking t(11;17), which were subsequently shown to have underlying PLZF/RARA fusions. The PLZF/RARA cases were characterized by a predominance of blasts with regular nuclei, an increased number of Pelger-like cells, and by expression of CD56 in 4 of 6 cases tested. Use of this classification system, combined with an analysis for CD56 expression, should allow early recognition of APL cases requiring tailored molecular investigations. (Blood. 2000;96:1287-1296)


Assuntos
Leucemia Promielocítica Aguda/classificação , Leucemia Promielocítica Aguda/patologia , Proteínas de Ligação a DNA/genética , Rearranjo Gênico , Humanos , Fatores de Transcrição Kruppel-Like , Leucemia Promielocítica Aguda/genética , Proteínas de Fusão Oncogênica/genética , Proteína com Dedos de Zinco da Leucemia Promielocítica , Receptores do Ácido Retinoico/genética , Receptor alfa de Ácido Retinoico , Fatores de Transcrição/genética
19.
Leukemia ; 14(1): 123-8, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10637487

RESUMO

The CD40 antigen is a member of the tumor necrosis factor receptor superfamily which interacts with its ligand and regulates the immune response via a dialogue between T-lymphocytes and antigen-presenting or tumor cells. Tumor triggering via CD40 exerts direct effects on cancer cells, which have mainly been investigated in terminally differentiated hematological malignancies such as low-grade lymphoma. We focused our attention on minimally differentiated acute myeloid leukemia (AML-M0), an aggressive hematological malignancy in which severe prognosis suggests the requirement for innovative therapeutic strategies. Here we demonstrate, for the first time to our knowledge, a CD40-triggered IL-8, RANTES and IL-12 secretion by leukemic cells. Supernatants from CD40-stimulated leukemia cells had chemoattractant effects on T-lymphocytes, natural killer cells and monocytes. Moreover, these supernatants, when complemented with low-dose IL-2, induced significant lymphokine-activated and natural killer cytotoxicity, leading to leukemia lysis both in allogenic HLA-matched and autologous settings. Stimulation of leukemia cells via CD40 could participate significantly to the anti-leukemia immune response by contributing to the development of an inflammatory response and to in situ cytotoxicity. Leukemia(2000) 14, 123-128.


Assuntos
Antígenos CD40/imunologia , Citotoxicidade Imunológica/imunologia , Leucemia Mieloide/imunologia , Leucócitos/imunologia , Doença Aguda , Quimiocinas/metabolismo , Fatores Quimiotáticos , Citometria de Fluxo , Humanos , Interleucina-12/metabolismo , Leucemia Mieloide/metabolismo
20.
Leukemia ; 14(12): 2103-11, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11187899

RESUMO

The expression of the surrogate light chain (psiL) - made of the lambda-like (or lambda5) and the VpreB proteins - is a B cell-specific maturation marker. Using an anti-human VpreB mAb (4G7), we recently identified in human normal bone marrows, proB and preB cells that express the psiH-psiL proB (proBCR) and the mu-psiL preB (preBCR) receptors, respectively. In the present study, FACS and biochemical analysis confirm the broad proB and preB reactivity of the 4G7 mAb that contrasts with the narrow specificity of other available anti-psiL reagents for preB cells. This mAb was used to explore intracytoplasmic and cell surface expression of the VpreB protein on a series of 92 precursor B cell ALLs (from 40 child and 52 adult patients), in combination with 24 other mAbs. The major result concerns the identification within proB (or BI) and common (or BII) ALLs, of proBCR and proBCR+ ALLs that express the VpreB in the cytoplasm or at the cell surface, respectively. The percentage of ALLs within these two VpreB sub-groups differ considerably between the ALL origin. In the pediatric series, ALLs present in the majority a proBCR+ phenotype whereas we observed a proBCR+ phenotype for adult ALLs. Based on VpreB expression, and in combination with other published data, we propose a refined classification for precursor B cell ALLs.


Assuntos
Anticorpos Monoclonais/imunologia , Linfoma de Burkitt/imunologia , Adulto , Linfoma de Burkitt/classificação , Criança , Citometria de Fluxo , Humanos , Imunofenotipagem , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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