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2.
Minerva Anestesiol ; 77(5): 522-7, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21540807

RESUMEN

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.


Asunto(s)
Antígeno B7-2/biosíntesis , Antígenos HLA-DR/biosíntesis , Monocitos/metabolismo , Neoplasias/cirugía , Sepsis/inmunología , Adulto , Anciano , Procedimientos Quirúrgicos Electivos , Femenino , Citometría de Flujo , Humanos , Terapia de Inmunosupresión , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/inmunología , Periodo Posoperatorio , Sepsis/metabolismo
3.
Leukemia ; 23(2): 350-7, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18987664

RESUMEN

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.


Asunto(s)
Crisis Blástica/patología , Citometría de Flujo/métodos , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/patología , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Recuento de Células , Femenino , Humanos , Inmunofenotipificación , Cariotipificación , Masculino , Persona de Mediana Edad , Pronóstico , Inducción de Remisión , Adulto Joven
4.
Rev Med Interne ; 29(5): 424-35, 2008 May.
Artículo en Francés | MEDLINE | ID: mdl-18359538

RESUMEN

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.


Asunto(s)
Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Antineoplásicos/uso terapéutico , Humanos , Incidencia , Leucemia Linfocítica Crónica de Células B/epidemiología , Leucemia Linfocítica Crónica de Células B/mortalidad , Ensayos Clínicos Controlados Aleatorios como Asunto , Factores de Riesgo , Análisis de Supervivencia
5.
Bone Marrow Transplant ; 36(10): 901-6, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16151421

RESUMEN

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.


Asunto(s)
Eritropoyetina/administración & dosificación , Trasplante de Células Madre Hematopoyéticas/métodos , Hemoglobinas/efectos de los fármacos , Acondicionamiento Pretrasplante/métodos , Adulto , Anciano , Eritropoyesis/efectos de los fármacos , Eritropoyetina/toxicidad , Femenino , Neoplasias Hematológicas/terapia , Hemoglobinas/análisis , Humanos , Masculino , Persona de Mediana Edad , Agonistas Mieloablativos/uso terapéutico , Proyectos Piloto , Proteínas Recombinantes , Trasplante Homólogo
6.
Transfusion ; 44(4): 501-8, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15043564

RESUMEN

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.


Asunto(s)
Antineoplásicos/farmacología , Transfusión de Eritrocitos/estadística & datos numéricos , Eritropoyesis/efectos de los fármacos , Trasplante de Células Madre Hematopoyéticas/métodos , Acondicionamiento Pretrasplante/métodos , Adolescente , Adulto , Anciano , Antineoplásicos/uso terapéutico , Trasplante de Médula Ósea/efectos adversos , Femenino , Enfermedad Injerto contra Huésped/etiología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Hemoglobinas/análisis , Humanos , Cinética , Masculino , Persona de Mediana Edad , Trasplante de Células Madre de Sangre Periférica/efectos adversos , Valor Predictivo de las Pruebas , Pronóstico , Trasplante Homólogo
7.
Bone Marrow Transplant ; 32(11): 1059-64, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14625576

RESUMEN

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.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Eliminación de Componentes Sanguíneos/efectos adversos , Neoplasias de la Mama/terapia , Células Neoplásicas Circulantes/patología , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidad , Eliminación de Componentes Sanguíneos/normas , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Recuento de Células , Ciclofosfamida/administración & dosificación , Relación Dosis-Respuesta a Droga , Doxorrubicina/administración & dosificación , Femenino , Movilización de Célula Madre Hematopoyética , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Trasplante de Células Madre Hematopoyéticas/normas , Humanos , Persona de Mediana Edad , Metástasis de la Neoplasia/patología , Estudios Prospectivos , Análisis de Supervivencia , Resultado del Tratamiento
8.
Leukemia ; 16(10): 2129-33, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12357367

RESUMEN

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.


Asunto(s)
División Celular , Trasplante de Células Madre Hematopoyéticas , Linfocitos/citología , Adulto , Femenino , Hematopoyesis , Humanos , Leucemia/complicaciones , Leucemia/patología , Leucemia/terapia , Masculino , Persona de Mediana Edad , Acondicionamiento Pretrasplante , Trasplante Homólogo , Resultado del Tratamiento , Virosis/complicaciones
9.
Hematology ; 7(3): 157-64, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12243978

RESUMEN

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.


Asunto(s)
Trasplante de Médula Ósea/métodos , Células Dendríticas/citología , Sistema Inmunológico/citología , Subgrupos Linfocitarios/citología , Acondicionamiento Pretrasplante/métodos , Adulto , Linfocitos B/citología , Células Sanguíneas/citología , Linfocitos T CD8-positivos/citología , Femenino , Supervivencia de Injerto , Neoplasias Hematológicas/terapia , Humanos , Sistema Inmunológico/crecimiento & desarrollo , Inmunofenotipificación , Células Asesinas Naturales/citología , Leucocitos/citología , Masculino , Persona de Mediana Edad , Trasplante Homólogo , Trasplante Isogénico
10.
Leukemia ; 16(5): 855-60, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-11986947

RESUMEN

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.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Citotoxicidad Inmunológica , Leucemia Mieloide/patología , Receptores Inmunológicos , Enfermedad Aguda , Antígenos CD/metabolismo , Complejo CD3 , Antígeno CD48 , Antígeno CD56 , Linfocitos T CD8-positivos/citología , Linfocitos T CD8-positivos/ultraestructura , Humanos , Inmunofenotipificación , Leucemia Mieloide/metabolismo , Activación de Linfocitos/inmunología , Masculino , Glicoproteínas de Membrana/inmunología , Persona de Mediana Edad , Proteínas de Neoplasias/metabolismo , Familia de Moléculas Señalizadoras de la Activación Linfocitaria , Subgrupos de Linfocitos T/citología , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/ultraestructura
12.
Clin Lab Haematol ; 23(2): 81-90, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11488846

RESUMEN

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.


Asunto(s)
Antígenos CD55/inmunología , Antígenos CD59/inmunología , Hemoglobinuria Paroxística/inmunología , Eritrocitos/inmunología , Citometría de Flujo/métodos , Citometría de Flujo/normas , Granulocitos/inmunología , Hemoglobinuria Paroxística/sangre , Humanos
13.
Br J Haematol ; 113(4): 1047-50, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11442501

RESUMEN

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.


Asunto(s)
Linfoma de Burkitt/complicaciones , Linfoma de Burkitt/genética , Reordenamiento Génico de Cadena Pesada de Linfocito B , Linfoma de Células B Grandes Difuso/complicaciones , Linfoma de Células B Grandes Difuso/genética , Adulto , Antígenos CD/análisis , Antígenos de Diferenciación Mielomonocítica/análisis , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Linfoma de Burkitt/diagnóstico , Ciclofosfamida/administración & dosificación , Dacarbazina/administración & dosificación , Daunorrubicina/administración & dosificación , Humanos , Inmunohistoquímica , Antígenos Comunes de Leucocito/análisis , Linfoma de Células B Grandes Difuso/diagnóstico , Masculino , Reacción en Cadena de la Polimerasa , Proteínas S100/análisis
14.
Acta Haematol ; 105(3): 166-71, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11463991

RESUMEN

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.


Asunto(s)
Médula Ósea , Neoplasias de la Mama/patología , Células Epiteliales/patología , Médula Ósea/patología , Purgación de la Médula Ósea , Neoplasias de la Mama/secundario , Femenino , Trasplante de Células Madre Hematopoyéticas , Humanos , Trasplante Autólogo
15.
Bone Marrow Transplant ; 28(12): 1157-60, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11803360

RESUMEN

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.


Asunto(s)
Trasplante de Médula Ósea/efectos adversos , Efecto Injerto vs Tumor , Leucemia Mielógena Crónica BCR-ABL Positiva/terapia , Linfocitosis/etiología , Citotoxicidad Inmunológica , Humanos , Leucemia Mielógena Crónica BCR-ABL Positiva/inmunología , Masculino , Persona de Mediana Edad , Subgrupos de Linfocitos T/inmunología , Acondicionamiento Pretrasplante , Trasplante Homólogo
17.
Cancer Res ; 60(16): 4403-11, 2000 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-10969785

RESUMEN

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.


Asunto(s)
Antígenos CD34/inmunología , Antígenos de Diferenciación/inmunología , Apoptosis/fisiología , Células Dendríticas/patología , Leucemia Mieloide/patología , NAD+ Nucleosidasa/inmunología , Células Madre Neoplásicas/inmunología , Receptor fas/fisiología , ADP-Ribosil Ciclasa , ADP-Ribosil Ciclasa 1 , Enfermedad Aguda , Antibióticos Antineoplásicos/farmacocinética , Antibióticos Antineoplásicos/farmacología , Antígenos CD/biosíntesis , Apoptosis/efectos de los fármacos , Antígeno B7-1/biosíntesis , Antígeno B7-2 , Antígenos CD58/biosíntesis , Diferenciación Celular/fisiología , Daunorrubicina/farmacocinética , Daunorrubicina/farmacología , Células Dendríticas/inmunología , Resistencia a Antineoplásicos/genética , Proteína Ligando Fas , Expresión Génica , Antígenos HLA-DR/biosíntesis , Células Madre Hematopoyéticas/inmunología , Humanos , Leucemia Mieloide/inmunología , Leucemia Mieloide/metabolismo , Complejo Mayor de Histocompatibilidad/inmunología , Glicoproteínas de Membrana/biosíntesis , Glicoproteínas de Membrana/metabolismo , Glicoproteínas de Membrana/fisiología , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/metabolismo , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Receptor fas/metabolismo
18.
Blood ; 96(4): 1287-96, 2000 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-10942370

RESUMEN

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)


Asunto(s)
Leucemia Promielocítica Aguda/clasificación , Leucemia Promielocítica Aguda/patología , Proteínas de Unión al ADN/genética , Reordenamiento Génico , Humanos , Factores de Transcripción de Tipo Kruppel , Leucemia Promielocítica Aguda/genética , Proteínas de Fusión Oncogénica/genética , Proteína de la Leucemia Promielocítica con Dedos de Zinc , Receptores de Ácido Retinoico/genética , Receptor alfa de Ácido Retinoico , Factores de Transcripción/genética
19.
Leukemia ; 14(1): 123-8, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10637487

RESUMEN

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.


Asunto(s)
Antígenos CD40/inmunología , Citotoxicidad Inmunológica/inmunología , Leucemia Mieloide/inmunología , Leucocitos/inmunología , Enfermedad Aguda , Quimiocinas/metabolismo , Factores Quimiotácticos , Citometría de Flujo , Humanos , Interleucina-12/metabolismo , Leucemia Mieloide/metabolismo
20.
Leukemia ; 14(12): 2103-11, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11187899

RESUMEN

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.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Linfoma de Burkitt/inmunología , Adulto , Linfoma de Burkitt/clasificación , Niño , Citometría de Flujo , Humanos , Inmunofenotipificación , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
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