RESUMO
Amyloidosis is a collection of systemic diseases characterised by misfolding of previously soluble precursor proteins that become infiltrative depositions, thereby disrupting normal organ structure and function. In the heart, accumulating amyloid fibrils lead to progressive ventricular wall thickening and stiffness, resulting in diastolic dysfunction gradually progressing to a restrictive cardiomyopathy. The main types of cardiac amyloidosis are amyloid light chain (AL) amyloidosis caused by an underlying plasma cell dyscrasia, amyloid transthyretin (TTR) amyloidosis of wild-type (normal) TTR at older age (ATTRwt) and hereditary or mutant amyloid TTR (ATTRm) in which a genetic mutation leads to an unstable TTR protein. Overall survival is poor once heart failure develops, underlining the need for early referral and diagnosis. Treatment for AL amyloidosis has improved markedly over the last decades, and TTR amyloidosis gene silencers and orally available transthyretin stabilisers are ready to enter the clinical arena after recent positive outcome trials. Novel therapies aiming at fibril degradation with monoclonal antibodies are under investigation. In this review, we focus on 'red flag' signs and symptoms, diagnosis and management of cardiac amyloidosis which differs considerably from the general management of heart failure. Only by increasing awareness, prognosis for patients with this devastating disease can be improved.
RESUMO
Recent literature suggests that after non-myeloablative allogeneic (NMA) stem cell transplantation (SCT), the incidence of extramedullary (EM) relapse in multiple myeloma (MM) patients is increased and that these relapses have a poor prognosis. However, numbers on incidence and treatment outcome are scarce. We collected data from 54 relapsed MM patients from a total group of 172 treated with sequential autologous and allogeneic NMA SCT at seven transplantation centres. There were 43 (79.6%) systemic relapses, including 6 with concurrent EM localisation. Five patients had a local EM relapse only. Six patients relapsed with only bone involvement. Patients with deletion of chromosome 13 had a higher incidence of EM relapse (30.8 versus 5.6%, P=0.06). EM relapses were treated with donor lymphocyte infusion, radiotherapy, or chemotherapy, especially with novel agents. The response rate was 45.5%, which was not different when compared to patients without EM disease (54.1%). Overall survival and progression-free survival were not significantly different in patients with EM disease, when compared to those without EM disease. In conclusion, the incidence of relapse with EM disease following allogeneic NMA SCT was 20.4%. There was no negative impact of EM relapse on response rate, overall survival and progression-free survival.
Assuntos
Doadores Vivos , Transfusão de Linfócitos , Mieloma Múltiplo/prevenção & controle , Transplante de Células-Tronco , Adulto , Idoso , Deleção Cromossômica , Cromossomos Humanos Par 13/genética , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/genética , Mieloma Múltiplo/mortalidade , Recidiva , Taxa de Sobrevida , Transplante Autólogo , Transplante HomólogoRESUMO
BACKGROUND: Patients with hairy cell leukaemia (HCL) have an increased susceptibility to intracellular pathogens, such as mycobacteria and Listeria. Although several abnormalities of T-cell populations have been described in HCL, the effector mechanism responsible for the increased susceptibility to infections is not known. METHODS: Blood was collected from 11 patients with HCL and 22 age- and gender-matched volunteers. Proinflammatory cytokine production by freshly isolated mononuclear cells was stimulated with either lipopolysaccharide or various heat-killed microorganisms. Cytokine concentrations were assessed by specific ELISAs. RESULTS: We demonstrate that mononuclear cells harvested from HCL patients have a specific defect of IFNgamma production when stimulated with a broad panel of bacterial stimuli. In contrast, the production of other proinflammatory cytokines, such as TNF, IL-1beta and IL-6, did not differ between HCL patients and controls. CONCLUSION: The specific defect in IFNgamma production may play a role in the susceptibility of patients with hairy cell leukaemia towards intracellular pathogens.
Assuntos
Interferon gama/biossíntese , Leucemia de Células Pilosas/fisiopatologia , Adulto , Citocinas , Feminino , Humanos , Leucemia de Células Pilosas/diagnóstico , Masculino , Mycobacterium , Projetos PilotoRESUMO
Amyloid light chain (AL) amyloidosis and multiple myeloma (MM) are both clonal plasma cell disorders, and may be concurrently present in patients. However, symptomatic MM seldom develops in patients with AL amyloidosis, while the other way around is common. With this case report, we discuss the difficulties in the differential diagnosis between AL amyloidosis and MM, and extend on the possible mechanisms involved in the development of these overlapping disorders. In addition, we provide clinicians with tools that may help improve their management and monitoring of such patients.
Assuntos
Medula Óssea/patologia , Amiloidose de Cadeia Leve de Imunoglobulina/patologia , Mieloma Múltiplo/patologia , Doenças Ósseas Metabólicas/diagnóstico por imagem , Doenças Ósseas Metabólicas/etiologia , Humanos , Amiloidose de Cadeia Leve de Imunoglobulina/complicações , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/complicações , Insuficiência Renal Crônica/etiologiaRESUMO
The Dutch-Belgian Cooperative Trial Group for Hematology Oncology Group-65/German-speaking Myeloma Multicenter Group-HD4 (HOVON-65/GMMG-HD4) phase III trial compared bortezomib (BTZ) before and after high-dose melphalan and autologous stem cell transplantation (HDM, PAD arm) compared with classical cytotoxic agents prior and thalidomide after HDM (VAD arm) in multiple myeloma (MM) patients aged 18-65 years. Here, the long-term follow-up and data on second primary malignancies (SPM) are presented. After a median follow-up of 96 months, progression-free survival (censored at allogeneic transplantation, PFS) remained significantly prolonged in the PAD versus VAD arm (hazard ratio (HR)=0.76, 95% confidence interval (95% CI) of 0.65-0.89, P=0.001). Overall survival (OS) was similar in the PAD versus VAD arm (HR=0.89, 95% CI: 0.74-1.08, P=0.24). The incidence of SPM were similar between the two arms (7% each, P=0.73). The negative prognostic effects of the cytogenetic aberration deletion 17p13 (clone size ⩾10%) and renal impairment at baseline (serum creatinine >2 mg dl-1) on PFS and OS remained abrogated in the PAD but not VAD arm. OS from first relapse/progression was similar between the study arms (HR=1.02, P=0.85). In conclusion, the survival benefit with BTZ induction/maintenance compared with classical cytotoxic agents and thalidomide maintenance is maintained without an increased risk of SPM.
Assuntos
Bortezomib/administração & dosagem , Mieloma Múltiplo/tratamento farmacológico , Adolescente , Adulto , Idoso , Aberrações Cromossômicas/efeitos dos fármacos , Feminino , Seguimentos , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Masculino , Melfalan/uso terapêutico , Pessoa de Meia-Idade , Mieloma Múltiplo/mortalidade , Mieloma Múltiplo/patologia , Prognóstico , Intervalo Livre de Progressão , Talidomida/uso terapêutico , Transplante Autólogo/métodos , Adulto JovemRESUMO
The purpose of this study was to determine the role of pre-emptive donor lymphocyte infusion (pDLI) after partial T-cell-depleted allogeneic SCT in patients with multiple myeloma (MM). A cohort of 24 MM patients was treated with partial T-cell-depleted myeloablative SCT between December 1997 and April 2002. These patients were intended to receive pDLI after SCT. The overall response rate after SCT was 83% (20 of 24 patients) with 10 patients (42%) in complete remission (CR). Transplant-related mortality within 1 year after SCT was 29%. Thirteen patients (54%) received pDLI and four patients in partial remission reached CR. GVHD>grade I after pDLI developed in 4 out of 13 patients (30%). Four patients received therapeutic DLI, without preceding pDLI. Eleven patients (46%) are alive, with a median follow-up of 67 months (range, 48-100 months). Seven of these patients (29%) are in continuous CR (CCR), which was confirmed by a negative patient-specific IgH PCR in four patients. All seven patients in CCR received pDLI. Although myeloablative SCT in MM induces high toxicity, we show that the concept of T-cell depletion followed by pDLI is promising and needs to be investigated in a reduced-intensity conditioning setting.
Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Depleção Linfocítica , Mieloma Múltiplo/terapia , Linfócitos T/transplante , Adulto , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Quimeras de Transplante , Condicionamento Pré-Transplante/métodos , Transplante HomólogoRESUMO
Donor lymphocyte infusion (DLI) after allogeneic SCT induces complete remissions in approximately 80% of patients with relapsed CML in chronic phase, but some patients do not respond to DLI. We studied absolute numbers of dendritic cell (DC) subsets and chimerism in T cells and two subsets of blood DCs (myeloid DCs (MDCs) and plasmacytoid DCs (PDCs)) in relation to DLI-induced alloreactivity. Based on T cell and DC chimerism, we identified three groups. Four patients were completely donor chimeric in T cells and DC subsets. These patients had an early stage of relapse, and three of the four patients attained complete molecular remission (CMolR) without significant GVHD. Six patients were completely donor in T cells and mixed chimeric in DC subsets. All patients entered CMolR, but this was associated with GVHD in four and cytopenia in three patients. Five patients had mixed chimerism in T cells and complete recipient chimerism in MDC; only two patients entered CMolR. Our data suggest that the combination of donor T cells and mixed chimerism in DC subsets induces a potent graft-versus-leukemia (GVL) effect in association with GVHD. DLI in patients with an early relapse and donor chimerism in both T cells and DC subsets results in GVL reactivity without GVHD.
Assuntos
Células Dendríticas/imunologia , Efeito Enxerto vs Leucemia/imunologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/imunologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Transfusão de Linfócitos , Linfócitos T/imunologia , Quimeras de Transplante/imunologia , Adulto , Idoso , Doadores de Sangue , Feminino , Doença Enxerto-Hospedeiro/imunologia , Humanos , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Recidiva , Indução de RemissãoRESUMO
Hereditary haemochromatosis (HH) is a disease related to mutations in the HFE gene and can lead to progressive iron accumulation, especially in the liver, eventually resulting in organ damage. We have developed guidelines for the diagnosis and treatment of this disease according to CBO methodology (dutch institute for Healthcare Quality). The prevalence of clinical symptoms such as fatigue, arthropathies, impotence and diabetes mellitus among homozygotes was similar to that in a control population. Nevertheless, we recommend the assessment of serum iron indices when these symptoms remain unexplained. When transferrin saturation is >45% and ferritin exceeds local reference ranges, HFE mutations should be investigated. Homozygosity for the C282Y mutation or combined C282Y/H63d mutation confirms the diagnosis of HFE-related HH. Liver biopsy is recommended when ferritin exceeds 1000 microg/l to establish the presence or absence of cirrhosis, which will affect prognosis and management. iron accumulation confirmed by magnetic resonance imaging (MRI) in the absence of the homozygous C282Y mutation or the combined C282Y/H63d genotype may justify a search for rare hereditary forms of non-HFE HH in a specialised centre. The literature supports the benefits of adequate phlebotomy and the screening of first-degree relatives of index patients with clinically overt HH. overall, the guidelines presented here are to a great extent based on the expert opinion of the working party, as the quantity of evidence that met predefined criteria posed by the evidence-based approach was small. We therefore recommend world-wide efforts to collaboratively address these remaining issues.
Assuntos
Hemocromatose/diagnóstico , Equipe de Assistência ao Paciente , Guias de Prática Clínica como Assunto , Genótipo , Hemocromatose/genética , Hemocromatose/terapia , Proteína da Hemocromatose , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Proteínas de Membrana/genética , Mutação , Países BaixosRESUMO
Allogeneic stem cell transplantation (allo-SCT) has the potential to induce sustained remissions in patients with multiple myeloma (MM). Currently, allo-SCT is primarily performed in high-risk MM patients, most often in the setting of early relapse after first-line therapy with autologous SCT. However, the implementation of allo-SCT for MM is jeopardized by high treatment-related mortality (TRM) rates as well as high relapse rates. In this systematic review, we aimed to identify a safe allo-SCT strategy that has optimal 1-year results regarding mortality, relapse and severe GvHD, creating opportunities for post-transplantation strategies to maintain remissions in the high-risk group of relapsed MM patients. Eleven studies were included. Median PFS ranged from 5.2 to 36.8 months and OS was 13.0 to 63.0 months. The relapse related mortality at 1 year varied between 0 and 50% and TRM between 8 and 40%. Lowest GvHD incidences were reported for conditioning regimens with T-cell depletion using ATG or graft CD34+ selection. Similar strategies could lay the foundation for a post-transplant immune platform, this should be further evaluated in prospective clinical trials.
Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Imunoterapia/métodos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/terapia , Condicionamento Pré-Transplante/métodos , Transplante Homólogo/métodos , Feminino , Humanos , Masculino , Mieloma Múltiplo/patologia , Recidiva Local de NeoplasiaRESUMO
In this retrospective study, we evaluated donor lymphocyte infusions given for relapsed (n=48) or persistent (n=15) myeloma following non-myeloablative allogeneic stem cell transplantation (Allo-SCT). Twenty-four of 63 patients (38.1%) responded: 12 patients (19.0%) with a partial response (PR) and 12 patients (19.0%) with a complete response (CR). Overall survival after donor lymphocyte infusions (DLI) was 23.6 months (1.0-50.7+). Median overall survival for non-responding patients was 23.6 months and has not been reached for the patients responding to DLI. In responders, progression-free survival after DLI was 27.8 months (1.2-46.2+). Patients with a PR had a median progression-free survival of 7.0 months, whereas patients with a CR to DLI had a median progression-free survival of 27.8 months. Major toxicities were acute graft-versus-host disease (GVHD) (38.1%) and chronic GVHD (42.9%). Seven patients (11.1%) died from treatment-related mortality. The only significant prognostic factors for response to DLI were the occurrence of acute and chronic GVHD. There was a trend towards significance for time between transplantation and DLI, and response. Donor lymphocyte infusion following non-myeloablative Allo-SCT is a valuable strategy for relapsed or persistent disease.
Assuntos
Transfusão de Linfócitos , Mieloma Múltiplo/terapia , Transplante de Células-Tronco , Doença Aguda , Adulto , Idoso , Doença Crônica , Intervalo Livre de Doença , Feminino , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/complicações , Mieloma Múltiplo/mortalidade , Recidiva , Indução de Remissão , Transplante de Células-Tronco/mortalidade , Transplante Homólogo , Resultado do TratamentoRESUMO
Although the mechanisms of therapeutic efficacy of cytosine arabinoside (Ara-C) are multifactorial, the pharmacodynamic basis for its cytotoxicity and therapeutic efficacy lies in its intracellular metabolism and the retention of the active metabolite, Ara-C triphosphate (Ara-CTP), which is a competitive inhibitor of DNA polymerase. Additional determinants of tumor cell sensitivity include Ara-CMP incorporation into cellular DNA, the size of the competing normal metabolite, deoxycytidine/5'-triphosphate pool, and the heterogeneity in growth kinetics of tumor cells, S-phase vs cells in other phases of the cell cycle. With high-dose Ara-C, substantial amounts of Ara-CTP are formed in phases of the cell cycle. The presence of high intracellular concentration with prolonged retention of Ara-CTP could lead to the inhibition of cell growth of the cells entering S-phase as a consequence of inhibition of DNA-polymerase and/or incorporation into cellular DNA, resulting in a chain termination. Pharmacokinetically, Ara-C is rapidly eliminated from plasma. In mice, pharmacokinetic parameters of Ara-C are not sufficient predictors for the observed differences in their in vivo antitumor activity. Although these mice were bearing different tumor types (L1210 Ara-C sensitive or P-388 relatively more resistant), the observed differences in tumor response were achieved under identical plasma Ara-C concentrations and area under the concentration time curve. The observed antitumor activity in L1210 cells is primarily associated with higher Ara-CTP pools and retention (T1/2 > 4 hr) in tumor cells as compared with normal bone marrow cells. In the least responsive tumor (P-388), although Ara-CTP pools were sufficiently high, retention of the drug in tumor cells and in normal cells is poor with a T1/2 < 2 hr. Thus, unlike mice bearing leukemia L1210 cells, alteration of the mode and dose of administration of Ara-C in mice bearing P-388 could only result in increased host toxicity with no therapeutic gain. Similarly in patients with acute nonlymphocyte leukemia (ANLL), there is no significant correlation between plasma Ara-C concentration and the intracellular concentrations or retentions of Ara-CTP. In some patients the highest Ara-CTP pools in leukemic myeloblast cells are achieved at a lower level of plasma Ara-C and decrease further with the increase of plasma Ara-C. Thus, in the in vivo model system and in ANLL patients with no prior chemotherapy, Ara-CTP retention is a critical factor associated with response to this agent, in particular its direct association with duration of complete response.(ABSTRACT TRUNCATED AT 400 WORDS)
Assuntos
Citarabina/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Animais , Ensaios Clínicos como Assunto , Ensaios de Seleção de Medicamentos Antitumorais , HumanosRESUMO
The change in phenotype, number and proliferative capacity of peripheral blood hematopoietic progenitors (PBHP) was studied in six patients with multiple myeloma during hematopoietic recovery after mobilization with high-dose cyclophosphamide and GM-CSF or G-CSF. In all six patients the first CD34+ cells appearing in the peripheral blood (PB) after cytoreductive treatment were predominantly CD34+/33- (> 70%). At later stages when leukapheresis procedures were started, the CD34+/33+ cells predominated in five of six patients. In leukapheresis harvests of peripheral blood, and in bone marrow addition of SCF and IL-6 to the culturing medium enhanced the plating efficiency. In peripheral blood an increase from 12 to 22% for CD34+/33+ and from 6 to 14% for CD34+/33- was observed. In normal bone marrow we observed an increase from 15 to 23% for CD34+/33+ and from 7 to 17% for CD34+/33-. Highly proliferative progenitors (>500 cells) in the CD34+/33- fraction appeared to be dependent on the addition of 'stem cell recruiting factors' (SCF and IL-6); in bone marrow the percentage of wells with >500 cells increased from 0.9 to 12.6% after SCF+IL-6 and in PBHP from 2 to 9%. We conclude that the first progenitors appearing in the peripheral blood after priming with high-dose cyclophosphamide and GM- or G-CSF have a more primitive immunophenotype, CD34+/33-.
Assuntos
Ciclofosfamida/administração & dosagem , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Células-Tronco Hematopoéticas/patologia , Mieloma Múltiplo/sangue , Adulto , Antígenos CD/análise , Antígenos CD34 , Antígenos de Diferenciação Mielomonocítica/análise , Medula Óssea/patologia , Ensaio de Unidades Formadoras de Colônias , Feminino , Citometria de Fluxo , Fatores de Crescimento de Células Hematopoéticas/farmacologia , Humanos , Imunofenotipagem , Interleucina-6/farmacologia , Leucaférese , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/terapia , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico , Fator de Células-TroncoRESUMO
Patients with acute myeloid leukaemia with maturation (AML-M2) that carried the t(8;21) were tested for the presence of chimeric AML1/ETO mRNA. After RT-PCR, an expected band of 208 bp was observed on gel, as well as some slower migrating bands. The base composition of one of the additional products was determined and was found to contain a new 68-bp ETO sequence present at the fusion of AML1 and ETO genes. The derived protein sequence results in a truncated AML1 gene still containing the putative DNA binding domain. Molecular diversity in the AML1-ETO transcripts will have consequences for the detection of minimal residual disease and antisense studies.
Assuntos
Cromossomos Humanos Par 21 , Cromossomos Humanos Par 8 , Proteínas de Ligação a DNA , Leucemia Mieloide Aguda/genética , Proteínas de Neoplasias/genética , Proteínas de Fusão Oncogênica/genética , Proteínas Proto-Oncogênicas , RNA Mensageiro/genética , Fatores de Transcrição , Translocação Genética , Sequência de Bases , Subunidade alfa 2 de Fator de Ligação ao Core , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , DNA Polimerase Dirigida por RNARESUMO
The feasibility of adding both the multidrug resistance modulator cyclosporin (CsA) and granulocyte colony-stimulating factor (G-CSF) to a standard salvage regimen of idarubicin (IDA) and cytarabine was evaluated in patients with resistant or relapsed acute myeloid leukemia and myelodysplastic syndrome. Three patients received IDA 12 mg/m2/day, the next four patients 9 mg/m2/day. The dose of CsA was 16 mg/kg/day. Six patients showed Pgp expression and none MRP1 expression. Grade III or IV toxicity (CTC-NCIC criteria) was registered in six patients for gastrointestinal, two patients for cardiovascular and one patient for neurological complications. Three patients died in hypoplasia and three patients showed leukemic regrowth. Three control patients were treated with IDA 12 mg/m2/day and cytarabine, but no CsA and G-CSF. The plasma IDA and idarubicinol (ida-ol) area under the curve's of patients treated with IDA 12 mg/m2 plus CsA were higher (P< 0.05) than in controls. Cellular IDA concentrations were almost similar, but cellular ida-ol concentrations were significantly higher (P < 0.05) in the presence of CsA than in controls. We conclude that the toxicity either with IDA 12 or 9 mg/m2/day was too high. The modulating effect of CsA was mainly based on changes in plasma kinetics of IDA and ida-ol, although ida-ol cellular clearance was delayed in the presence of CsA.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Ciclosporina/metabolismo , Daunorrubicina/farmacocinética , Idarubicina/farmacocinética , Leucemia Mieloide/tratamento farmacológico , Doença Aguda , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ciclosporina/farmacologia , Ciclosporina/uso terapêutico , Daunorrubicina/análogos & derivados , Daunorrubicina/metabolismo , Feminino , Humanos , Idarubicina/metabolismo , Imunossupressores/farmacologia , Imunossupressores/uso terapêutico , Leucemia Mieloide/metabolismo , Leucemia Mieloide/patologia , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , RecidivaRESUMO
Since in AML differentiation is abnormal but not absent, a hierarchy of stem cells, progenitor cells and more differentiated cells is postulated. The leukemic stem cell might also be characterized by the expression of CD34 and the absence of differentiation markers. Bone marrow samples of 33 AML patients, including 10 patients both at presentation and after relapse, were double labeled for CD34 and CD33. In 14/33 AML less than 1% of the labeled cells were found in the CD34+/33- fraction. After relapse a certain shift towards a more primitive phenotype was observed, but in 4/5 relapsed AML the CD34+/33- fraction remained below 1%. Single cells from the different subfractions were cultured and showed heterogeneous cluster and colony growth in both the CD34-/33+ and CD34+/33+ fraction. More colonies were observed in the CD34+/33- fraction. In AML with a more 'mature' phenotype (low number of CD34+/CD33- cells), highly proliferative myeloid, erythroid and mixed colonies could be cloned exclusively from this small CD34+/33- fraction. In five patients with numerical chromosomal abnormalities all these highly proliferative colonies appeared disomic using in situ hybridization (ISH) with centromeric probes. Based on these data we conclude that the CD34+/33- cell fraction in AML with a more mature immunophenotype (small fraction of cells CD34+/33-) comprise residual normal progenitors, while no primitive leukemic progenitors could be identified.
Assuntos
Antígenos CD/análise , Antígenos de Diferenciação Mielomonocítica/análise , Antígenos de Neoplasias/análise , Medula Óssea/patologia , Separação Celular , Leucemia Mieloide/patologia , Células-Tronco Neoplásicas/patologia , Doença Aguda , Antígenos CD34 , Diferenciação Celular , Aberrações Cromossômicas , Humanos , Imunofenotipagem , Hibridização In Situ , Leucemia Mieloide/genética , Células-Tronco Neoplásicas/química , Células-Tronco Neoplásicas/imunologia , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico , Células Tumorais Cultivadas , Ensaio Tumoral de Célula-TroncoRESUMO
In an earlier study we observed residual normal colonies in the CD34+, lineage-negative fraction in AML with a differentiated phenotype. The phenotype of both normal and leukemic progenitors in AML M2, t(8;21) was the subject of this study. The specific translocation enabled discrimination of normal and leukemic cells. Bone marrow samples from eight patients were evaluated for CD34 and the differentiation markers CD33, CD19 and CD56. Growth in all phenotypic fractions was measured in a single cell assay, which enabled quantification of plating efficiency, colony size and determination of progenitor cell origin. No growth was observed in the CD34-negative fraction. In the CD34+, lineage-positive fraction only clusters up to 20 cells were found in 6/8 samples. In 7/8 samples highly proliferative myeloid, erythroid and mixed colonies were cloned from the CD34+/CD56-CD19-CD33- fraction with a frequency between 1 and 12%. Such large colonies grew at a lower frequency (1-6%) from the CD34+/CD56 fraction (4/8 samples), the CD34+/CD56-CD19- fraction (5/8 samples) and from the CD34+/CD19- fraction (1/8 samples), respectively. Among the colonies consisting of more than 150 cells, only 3/45 evaluated were positive for the AML1/ETO fusion transcript. On the other hand, 8/19 colonies with less than 150 cells were AML1/ETO positive. This study shows that like normal progenitors leukemic progenitors are also present exclusively in the lineage-negative fraction in AML M2 t(8;21). A similar hierarchy of proliferation and differentiation was found for these leukemic progenitors, the smaller colony size fitting with their limited proliferation capacity. The frequency of leukemic progenitors was in the same range as their normal counterparts and detectable only after enrichment for the CD34+, lineage-negative population.
Assuntos
Antígenos CD34/imunologia , Cromossomos Humanos Par 21 , Cromossomos Humanos Par 8 , Células-Tronco Hematopoéticas/patologia , Leucemia Mieloide Aguda/genética , Translocação Genética , Sequência de Bases , Divisão Celular , Separação Celular , Primers do DNA , Células-Tronco Hematopoéticas/imunologia , Humanos , Imunofenotipagem , Leucemia Mieloide Aguda/patologia , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
The pattern of X-chromosome inactivation (XCIP), or Lyonization, can be used to distinguish monoclonal from polyclonal cell populations in females. However, a skewed XCIP exists in hematopoietic cells in approximately 40% of healthy elderly females, interfering with interpretation of clonality assays. In hematopoiesis, an active stem cell pool is assumed to be present within a larger population of inactive stem cells, with a continuous exchange of cells between the two compartments. The assumption that the active stem cell pool size decreases with age may explain the phenomenon of acquired skewing occurring by chance and predicts the XCIP of this population to fluctuate. This fluctuation should be reflected in the XCIP of peripheral granulocytes. We examined the XCIP for fluctuations in time in peripheral granulocytes, monocytes and T cells of young, middle-aged and elderly healthy females. We used an optimized HUMARA PCR assay that eliminates unbalanced DNA amplification. We found no fluctuations in XCIP in any age group in up to 18 months follow-up. We conclude that acquired skewing arises gradually in life without fluctuations in XCIP and that analysis at multiple time points cannot distinguish monoclonal hematopoiesis from normal, skewed hematopoiesis.
Assuntos
Mecanismo Genético de Compensação de Dose , Hematopoese/genética , Cromossomo X/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/genética , DNA/análise , Primers do DNA/química , DNA de Neoplasias/análise , Desoxirribonuclease HpaII/metabolismo , Feminino , Granulócitos/citologia , Células-Tronco Hematopoéticas/citologia , Humanos , Pessoa de Meia-Idade , Monócitos/citologia , Reação em Cadeia da Polimerase/métodos , Receptores Androgênicos/genética , Linfócitos T/citologiaRESUMO
Bone marrow plasma cells constitute the bulk of malignant cells in multiple myeloma patients. B-lymphocytes having immunoglobulin heavy chain gene rearrangements identical to those of the malignant clone (clonally related B-lymphocytes) may function as malignant plasma cell precursors. We and others proposed the use of anti-idiotypic antibodies to isolate and study clonally related B-lymphocytes. This strategy failed until now because anti-idiotypic antibodies raised by conventional hybridoma techniques proved to react frequently with epitopes shared by different idiotypes. Recently, we succeeded in selecting specific single chain Fv antibodies from phage libraries. To select single chain Fv bearing phages specifically directed against the immunoglobulin idiotype expressed by myeloma tumor cells we panned a semisynthetic phage library against purified myeloma paraprotein Fab fragments. The selection was performed in the presence of soluble polyclonal immunoglobulin as a competitor. Three independent selections for three myeloma patients yielded 10-26 clones. Between two and seven of the selected clones were reactive with patient Fab and not with polyclonal immunoglobulin in enzyme-linked immunosorbent assays. Five out of six anti-idiotypic single chain Fvs were able to specifically stain fixed monoclonal plasma cells in myeloma bone marrow. Idiotype specificity of these single chain Fvs was confirmed by flow cytometry since they did not react with monoclonal plasma cells of other patients, a panel of nine myeloma cell lines, isolated polyclonal bone marrow plasma cells and cultured B-lymphocytes. Using these anti-idiotypic reagents we were able to detect 25 myeloma plasma cells in a background of 50000 immunoglobulin isotype-matched cells of the myeloma cell line UM-1 or 50000 donor bone marrow cells (sensitivity 0.05%). This paper shows that highly specific anti-idiotypic single chain Fv antibody fragments selected from a phage display library can be used to detect rare idiotypic cells in patient samples.
Assuntos
Anticorpos Anti-Idiotípicos/imunologia , Mieloma Múltiplo/imunologia , Proteínas Musculares , Plasmócitos/imunologia , Animais , Especificidade de Anticorpos , Linfócitos B/imunologia , Bacteriófago M13 , Células Cultivadas , Conectina , Fibroblastos/metabolismo , Genes myc , Humanos , Fragmentos Fab das Imunoglobulinas/imunologia , Camundongos , Proteínas do Mieloma/imunologia , Biblioteca de Peptídeos , Células Tumorais Cultivadas , Vírus da Estomatite Vesicular IndianaRESUMO
Myelodysplastic syndromes (MDS) are highly proliferative bone marrow (BM) disorders where the primary lesion presumably affects a CD34+ early progenitor or stem cell. We investigated the proliferative characteristics of CD34+ cells of 33 untreated MDS patients (19 RA, 5 RARS, 7 RAEB, 2 RAEBt) and five patients with acute myeloid leukemia after MDS (sAML). All patients received a 1-h infusion of the thymidine analogue iodoor bromodeoxyuridine intravenously before a BM aspirate and biopsy was taken. A double-labeling immunohistochemistry technique by monoclonal anti-CD34 (QBend/10) and anti-IUdR/BrdU antibodies was developed and performed. By this technique we recognised CD34+ and CD34- cells actively engaged in DNA synthesis or not. As MDS evolves a significant increase occurred in the percentage of CD34+ cells of all myeloid cells (mean value: RA/RARS 1.67%; RAEB(t) 8.68%; sAML 23.83%) as well as in the percentage of proliferating CD34+ cells of all myeloid cells (RA/RARS 0.19%; RAEB(t) 0.43%; and sAML 3.30%). This was associated with a decreasing trend in the overall myeloid labeling index (LI: RA/RARS 25.8%, RAEB(t) 24.6% and sAML 21.5%). This decrease in overall myeloid LI is due to an exponential increase in the proportion of CD34+ cells of the proliferating compartment during MDS evolution (RA/RARS 0.35%, RAEB(t) 1.44% and sAML 11.98% of all S-phase cells). These CD34+ cells appeared to proliferate more slowly than their more mature CD34 negative counterparts, since we found a progressive increment in the mean total cell cycling time (Tc) of all myeloid cells during MDS progression (RA/RARS 39.8, RAEB(t) 45.2 and sAML 65.8 h). This study showed that during MDS evolution to sAML the CD34+ compartment develops a growth advantage leading to apparent expansion.