Factors affecting hematopoietic progenitor cell mobilization: An analysis of 307 patients

We reviewed the data of 307 patients treated with autologous bone marrow transplantation with the aim to identify factors associated with poor hematopoietic stern cell (HSC) mobilization after administration of cyclophosphamide and granulocyte-colony stimulating factor. Success in mobilization was defined when >= 2.0 x 10(6) CD34+ cells/kg weight could be collected with <= 3 leukapheresis procedures. Success was observed in 260 patients (84.7%) and nonsuccess in 47 patients (15.3%). According to the stepwise regression model: diagnosis, chemotherapy load, treatment with mitoxantrone and platelet count before mobilization were found to be independent predictive factors for HSC mobilization. These results could help in the previous recognition of patients at risk for non response to mobilization and allow to plan an alternative protocol for this group of patients. (C) 2008 Elsevier Ltd. All rights reserved

Criopreservação de medula óssea e células pluripotentes periféricas utilizando um congelador programável: experiência em 86 congelamentos Cryopreservation of bone marrow and peripheral blood stem cells using a controlled rate freezing system. Experience on 86 procedures

A infusão de células hematopoéticas totipotentes criopreservadas permite a recuperação da hematopoese após quimioterapia mieloablativa. OBJETIVO. A formação de cristais de gelo durante o processo de congelamento é o fator principal que causa ruptura das estruturas celulares. A criopreservação dessas células a uma taxa constante preveniria os danos causados pelo congelamento brusco. MÉTODOS. Vinte e três pacientes com mediana de 25 anos (variação 3-57) tiveram a medula óssea e/ou células-tronco periféricas (CTP) coletadas no período de março de 1993 a outubro de 1994, totalizando 86 congelamentos. Os pacientes apresentavam as seguintes neoplasias: linfoma não-Hodgkin (n=5), leucemia mielóide aguda (n=8), leucemia linfóide aguda (n=6), doença de Hodgkin (n=3) e mieloma múltiplo (n=1). O congelamento foi controlado por um computador, acoplado ao sistema, às seguintes temperaturas: -1°C/min até -45°C e depois a -10°C/min até -80°C. Após o congelamento, as células foram mantidas em freezer a -110°C até o momento da infusão. Para obtenção das CTP, empregou-se o fator de crescimento estimulante de granulócitos (G-CSF). RESULTADOS. Uma mediana de 3,16 x 10(8) céls./kg (variação 0,86-24,22) de CTP e 2,03 x 10(8) céls./kg (variação 0,19-12,21) de medula óssea foi congelada. A mediana para atingir granulócitos maior ou igual a 500/µL e plaquetas maior que 20.000/µL foi de 12 dias (variação 8-40) e 31 dias (variação 8-80), respectivamente. Todos os pacientes tiveram recuperação hematopoética após a infusão das células criopreservadas. CONCLUSÃO. A criopreservação em congelador programável permite o armazenamento de células hematopoéticas e, potencialmente, pode causar menor dano celular.<br>The cryopreservation of hematopoietic stem cells can be used for rescuing the hematopoiesis after high dose chemotherapy. PURPOSE. The ice cristal formation during the freezing procedure is the key point that can be harmful to the cells. The cryopreservation of hematopoietic stem cells in a controlled-rate freezer could decrease the cell damage. METHODS. Twenty-three patients with a median age of 26 years (range 03-57) had bone marrow and/or peripheral blood stem cells harvested from March 1993 through October 1994, ending up to 86 freezing procedures. The patient's diagnoses are as follows: Non-Hodgkin's Lymphoma (n=5); Acute Myelogenous Leukemia (n=8); Acute Lymphocytic Leukemia (n=6); Hodgkin's disease (n=3); Multiple Myeloma (n=1). The cells were frozen away in a controlled-rate freezer chamber at the folowing rate: -1°C/min from room temperature to -45°C and then, at -10°C/min down to -80°C. After freezing, the cells were kept into mechanical freezers until the marrow infusion. To mobilize PBSC (peripheral blood stem cells), G-CSF (granulocyte colony stimulating factor) was given. RESULTS. A median of 3.16x10(8) cells/kg (range 0.86-24.22) of PBSC and 2.03x10(8) cells/kg (0.19-12.21) of bone marrow cells were frozen. The median time to reach granulocytes greater than 500/µL and platelets greater than 20,000/µL was 12 days (range 8-40) and 31 days (range 8-80), respectively. All patients had marrow engraftment after infusion of hematopoietic stem cells. CONCLUSION. The cryopreservation procedure using a controlled-rate freezer can store hematopoietic stem cells and potentially, cause less damage to the cells