RESUMEN
Patients who have undergone autologous stem cell transplantation are subsequently more susceptible to chemotherapy-induced bone marrow toxicity. In the present study, bone marrow primitive progenitor cells were examined one year after autologous stem cell transplantation and compared with normal bone marrow and mobilized peripheral blood stem cells. Post-transplantation bone marrow contained a significantly lower percentage of quiescent cells in the CD34(+)/CD38(low) fraction compared to normal bone marrow. In addition, we observed a strong decrease in stem cell/primitive progenitor frequency in post-transplantation CD34(+) cells as defined by long-term culture assays. Measurement of the levels of reactive oxygen species by flow cytometry revealed comparable levels in post-transplantation and normal bone marrow CD34(+)/CD38(low) cells, while significantly higher levels of reactive oxygen species were observed in CD34(+)/CD38(high) cells following autologous stem cell transplantation compared to normal bone marrow. Moreover, post-transplantation CD34(+) bone marrow cells demonstrated an increased sensitivity to buthionine sulfoximine, a trigger for endogenous production of reactive oxygen species. Gene expression analysis on CD34(+) cells revealed a set of 195 genes, including HMOX1, EGR1, FOS and SIRPA that are persistently down-regulated in mobilized peripheral blood cells and post-transplantation bone marrow compared to normal bone marrow. In conclusion, our data indicate that the diminished regenerative capacity of bone marrow following autologous stem cell transplantation is possibly related to a loss of quiescence and a reduced tolerability to oxidative stress.
Asunto(s)
ADP-Ribosil Ciclasa 1/fisiología , Antígenos CD34/fisiología , Trasplante de Células Madre Hematopoyéticas/tendencias , Adulto , Anciano , Células Cultivadas , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Especies Reactivas de Oxígeno/metabolismo , Factores de Tiempo , Trasplante Autólogo/tendenciasRESUMEN
BACKGROUND: Currently there is no sensitive laboratory test to establish the influence of red blood cells (RBCs) on hemostasis. As thromboelastography (TEG) measures hemostasis in whole blood, taking into account the interactions of all cellular elements, we used this instrument to investigate the role that RBCs play in hemostasis. STUDY DESIGN AND METHODS: In 29 patients with chemotherapy-induced anemia we studied the effect of progressive anemia on the coagulation profile. In 24 patients with chronic anemia we studied the effect of transfusion of RBCs on coagulation. Finally, in 18 patients we evaluated whether storage time of RBCs has additional effects on hemostasis. RESULTS: We observed a significant negative correlation between hemoglobin and TEG variables related to both clot strength and elasticity (p < 0.05). Moreover, anemia was associated with a delay in the initiation of the coagulation cascade. Correction of anemia by RBC transfusion resulted in significant shortening of this initiation phase with now the opposite effect on clot strength and elasticity. The negative effects on clot quality were significantly worse when fresh RBCs were transfused compared to longer-stored RBCs. Furthermore, in contrast to the longer-stored RBCs, fresh RBCs did not enhance initial fibrin formation. CONCLUSIONS: In this study we found that anemia was associated with a delay in the initiation of the coagulation cascade with a finally formed clot with superior strength and viscoelastic properties. Transfusion of RBCs was associated with impaired clot quality, with even worse effects on the initial fibrin build-up and clot quality by fresh RBCs.
Asunto(s)
Eritrocitos/fisiología , Hemostasis , Adulto , Anciano , Anemia/sangre , Plaquetas/fisiología , Transfusión de Eritrocitos , Femenino , Hemoglobinas/análisis , Humanos , Masculino , Persona de Mediana Edad , TromboelastografíaRESUMEN
BACKGROUND: Our objective was to analyze the effects of age, gender, and the use of oral contraceptives (OCs) on coagulation using thrombelastography (TEG), a single test to analyze both plasma coagulation factors and cellular elements in whole blood. METHODS: TEG variables were measured in native whole blood and in recalcified citrated blood from 120 healthy adults (60 men and 60 women) with various ages and in an additional 29 healthy women using OCs. RESULTS: We observed hypercoagulability in women compared with men and in women using OCs compared with age-matched nonusers. Moreover, we found hypercoagulability with aging. Using the method of Bland and Altman (Lancet 1986;1:307-10), we demonstrated no correlation between TEG measurements in native and recalcified citrated blood. CONCLUSIONS: Aging, female gender, use of OCs, and low-normal hematocrit levels have significant procoagulant effects. TEG measurements in native and recalcified citrated blood are not interchangeable, as indicated by differences between the 2 measurements ranging from 20% in maximal amplitude to 246% in clotting time. Furthermore, the limits of agreement strongly exceeded clinical acceptability to conclude interchangeability.
Asunto(s)
Envejecimiento/sangre , Coagulación Sanguínea/fisiología , Tromboelastografía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Recolección de Muestras de Sangre , Citratos/química , Femenino , Fibrina/química , Hematócrito , Hemoglobinas/metabolismo , Humanos , Indicadores y Reactivos , Modelos Lineales , Masculino , Persona de Mediana Edad , Caracteres Sexuales , Manejo de Especímenes , Trombosis/sangre , Adulto JovenRESUMEN
The predictive value of clinical and platelet kinetic parameters for treatment outcome in idiopathic thrombocytopenic purpura (ITP) was investigated in 75 patients with platelets
Asunto(s)
Plaquetas/efectos de los fármacos , Glucocorticoides/uso terapéutico , Prednisona/uso terapéutico , Púrpura Trombocitopénica Idiopática/tratamiento farmacológico , Trombopoyesis/efectos de los fármacos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Plaquetas/fisiología , Estudios de Casos y Controles , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Púrpura Trombocitopénica Idiopática/fisiopatología , Púrpura Trombocitopénica Idiopática/cirugía , Inducción de Remisión , Esplenectomía , Trombopoyesis/fisiologíaRESUMEN
Platelet kinetic studies in idiopathic thrombocytopenic purpura (ITP) have shown that in a subgroup of patients a shortened mean platelet life (MPL) is associated with a decreased platelet production rate (PPR). Other methods of studying certain aspects of thrombocytopoiesis are the plasma concentrations of thrombopoietin and glycocalicin.
Asunto(s)
Complejo GPIb-IX de Glicoproteína Plaquetaria/análisis , Púrpura Trombocitopénica/sangre , Trombopoyesis , Trombopoyetina/sangre , Adulto , Anciano , Plaquetas/patología , Médula Ósea/patología , Supervivencia Celular , Femenino , Humanos , Masculino , Persona de Mediana EdadAsunto(s)
Proteínas Portadoras/administración & dosificación , Inmunoglobulinas Intravenosas/administración & dosificación , Factores Inmunológicos/administración & dosificación , Púrpura Trombocitopénica Idiopática/tratamiento farmacológico , Receptores Fc/administración & dosificación , Enfermedad Crónica , Femenino , Hemorragia/sangre , Hemorragia/etiología , Hemorragia/prevención & control , Humanos , Masculino , Recuento de Plaquetas , Púrpura Trombocitopénica Idiopática/sangre , Púrpura Trombocitopénica Idiopática/complicaciones , Proteínas Recombinantes de Fusión , TrombopoyetinaRESUMEN
The effect of recombinant factor VIIa (rFVIIa) on blood loss was evaluated in cirrhotic patients undergoing orthotopic liver transplantation. In the present study, we explored the effect of rFVIIa on coagulation and fibrinolysis during orthotopic liver transplantation. Coagulation factors, parameters of thrombin generation and parameters of fibrinolysis were measured in six patients who had received a single dose of 80 micro g/kg rFVIIa and in ten controls, during and after orthotopic liver transplantation. Baseline concentrations and course of coagulation factors were similar in patients and controls. Thrombin generation did not rise after the administration of rFVIIa, but showed a sharp increase after reperfusion in patients, as compared with controls. No difference in fibrinolysis was apparent between patients and controls. No evidence of diffuse intravascular coagulation was seen. We conclude that the use of rFVIIa in orthotopic liver transplantation seems to enhance thrombin generation in a localized and time-limited matter, without causing systemic coagulation.
Asunto(s)
Antifibrinolíticos/uso terapéutico , Coagulación Sanguínea/efectos de los fármacos , Factor VII/uso terapéutico , Fibrinólisis/efectos de los fármacos , Trasplante de Hígado , Proteínas Recombinantes/uso terapéutico , Adulto , Factores de Coagulación Sanguínea/análisis , Pérdida de Sangre Quirúrgica/prevención & control , Plaquetas/efectos de los fármacos , Transfusión Sanguínea , Relación Dosis-Respuesta a Droga , Factor VIIa , Femenino , Humanos , Cirrosis Hepática/sangre , Cirrosis Hepática/cirugía , Trasplante de Hígado/métodos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Estadística como Asunto , Trombina/efectos de los fármacos , Factores de TiempoRESUMEN
RATIONALE: A discordant relationship between bone marrow cellularity and peripheral blood findings is regularly noticed in patients with aplastic anemia (AA). Therefore, the feasibility of 3-F-18 fluoro-3-deoxy-L-thymidine (F-18 FLT PET was tested as a noninvasive tool to visualize the total distribution of the hematopoietic bone marrow compartment in AA at presentation or after treatment. METHODS: In vivo scanning was performed with F-18 FLT PET in AA patients (n = 17), including patients upfront (n = 11) and following treatment (n = 6), in addition to peripheral blood cell counts and a bone marrow biopsy. RESULTS: A striking abnormal F-18 FLT scan was observed in all patients upfront treatment, in particular a reduced uptake of the pelvis was shown, the area that is biopsied for the bone marrow biopsy. Following treatment, the number of solitary lesions with increased proliferative activity outside the pelvis was noticed in patients with partial response, whereas patients with a complete remission showed a homogenous uptake throughout the skeleton. CONCLUSION: This pilot study demonstrates that F-18 FLT scan provides a highly distinctive overview of the bone marrow compartment in AA that might be helpful for making a proper diagnosis and monitoring treatment response of AA patients.
Asunto(s)
Anemia Aplásica/diagnóstico por imagen , Anemia Aplásica/inmunología , Médula Ósea/diagnóstico por imagen , Didesoxinucleósidos , Tomografía de Emisión de Positrones/métodos , Adulto , Anciano , Anciano de 80 o más Años , Anemia Aplásica/metabolismo , Didesoxinucleósidos/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Adulto JovenRESUMEN
To investigate underlying mechanisms of thrombocytopenia in myelodysplastic syndrome (MDS), radiolabeled platelet studies were performed in 30 MDS patients with platelet counts less than 100 x 10(9)/L. Furthermore, plasma thrombopoietin and glycocalicin index (a parameter of platelet or megakaryocyte destruction) were determined. Mean platelet life (MPL), corrected for the degree of thrombocytopenia, was reduced in 15 of 30 patients (4.3 +/- 0.9 days [mean +/- SD] vs 6.0 +/- 1.3, P = .0003). Platelet production rate (PPR) was reduced in 25 of 30 patients (68 +/- 34 x 10(9)/d vs 220 +/- 65, P < .0001). Thrombopoietin levels were not significantly correlated with the PPR. However, the glycocalicin index was significantly higher compared with controls (15 +/- 16 vs 0.7 +/- 0.2, P = .001) and significantly correlated with the PPR (P = .02, r = -0.5), but not with the MPL (P = 1.8). Ultrastructural studies demonstrated necrosis-like programmed cell death (PCD) in mature and immature megakaryocytes (n = 9). Immunohistochemistry of the bone marrow biopsies demonstrated no positive staining of MDS megakaryocytes for activated caspase-3 (n = 24) or cathepsin D (n = 21), while activated caspase-8 was demonstrated in a subgroup of patients (5/21) in less than 10% of megakaryocytes. These results indicate that the main cause of thrombocytopenia in MDS is caspase-3-independent necrosis-like PCD resulting in a decreased PPR in conjunction with an increased glycocalicin index.
Asunto(s)
Apoptosis , Plaquetas/patología , Megacariocitos/patología , Síndromes Mielodisplásicos/patología , Trombocitopenia/etiología , Anciano , Biomarcadores/sangre , Examen de la Médula Ósea , Caspasa 3 , Caspasas , Senescencia Celular , Femenino , Humanos , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/sangre , Síndromes Mielodisplásicos/complicaciones , Complejo GPIb-IX de Glicoproteína Plaquetaria/análisis , Trombopoyetina/sangreRESUMEN
To investigate whether altered megakaryocyte morphology contributes to reduced platelet production in idiopathic thrombocytopenic purpura (ITP), ultrastructural analysis of megakaryocytes was performed in 11 ITP patients. Ultrastructural abnormalities compatible with (para-)apoptosis were present in 78% +/- 14% of ITP megakaryocytes, which could be reversed by in vivo treatment with prednisone and intravenous immunoglobulin. Immunohistochemistry of bone marrow biopsies of ITP patients with extensive apoptosis showed an increased number of megakaryocytes with activated caspase-3 compared with normal (28% +/- 4% versus 0%). No difference, however, was observed in the number of bone marrow megakaryocyte colony-forming units (ITP, 118 +/- 93/105 bone marrow cells; versus controls, 128 +/- 101/105 bone marrow cells; P =.7). To demonstrate that circulating antibodies might affect megakaryocytes, suspension cultures of CD34+ cells were performed with ITP or normal plasma. Morphology compatible with (para-)apoptosis could be induced in cultured megakaryocytes with ITP plasma (2 of 10 samples positive for antiplatelet autoantibodies). Finally, the plasma glycocalicin index, a parameter of platelet and megakaryocyte destruction, was increased in ITP (57 +/- 70 versus 0.7 +/- 0.2; P =.009) and correlated with the proportion of megakaryocytes showing (para-) apoptotic ultrastructure (P =.02; r = 0.7). In conclusion, most ITP megakaryocytes show ultrastructural features of (para-) apoptosis, probably due to action of factors present in ITP plasma.