Trasplante alogénico de precursores hematopoyéticos de sangre de cordón umbilical de donante no emparentado: primera experiencia, en tres casos, con donantes del banco público chileno de células de cordón / Allogenic hematopoietic stem cell transplantation with unrelated cord blood: Report of three cases from the Chilean cord blood bank

Public cord blood banks are a source of hematopoietic stem cells for patients with hematological diseases who lack a family donor and need allogeneic transplantation. In June 2007 we started a cord blood bank with units donated in three maternity wards in Santiago, Chile. We report the first three transplants done with cord blood units form this bank. Cord blood units were obtained by intrauterine collection at delivery. They were depleted of plasma and red cells and frozen in liquid nitrogen. Tests for total nucleated cells, CD34 cell content, viral serology, bacterial cultures and HLA A, B and DRB1 were done. Six hundred cord blood units were stored by March 2012. Three patients received allogeneic transplant with cord blood from our bank, two with high risk lymphoblastic leukemia and one with severe congenital anemia. They received conditioning regimens according to their disease and usual supportive care for unrelated donor transplantation until full hematopoietic and immune reconstitution was achieved. The three patients had early engraftment of neutrophils and platelets. The child corrected his anemia and the leukemia patients remain in complete remission. The post-transplant course was complicated with Epstein Barr virus, cytomegalovirus and BK virus infection. Two patients are fully functional 24 and 33 months after transplant, the third is still receiving immunosuppression.

Identificación de células madres hematopoyéticas fetales y de adultos: mitos y realidades de los trasplantes / Identification of fetal and adults hematopoietic stem cells: myths and realities of the transplants

Las cédulas madres y hematopoyéticas son células indiferenciadas con una amplia capacidad de proliferación y de autorrenovación; están presentes en medula ósea (1%-3%) y en sangre (0,1%), identificándose por la expresión del marcador CD34. Pueden ser movilizadas desde la médula ósea a la sangre después de quimioterapia o con citoquinas, En este estudio se identificaron células madres en sangre de fetos, neonatos y adultos. Se analizaron 278 muestras de sangre de fetos de 17-32 semanas, neonatos, y en productos de aféresis de células madres de pacientes con enfermedades malignas. La cantidad de células CD34 ± disminuyó con el aumento de la edad gestacional de 6,10% a 1,03%. De estas células se obtuvo la formación de colonias granulocíticas y eritrocíticas en cultivos. En sangre de cordón se obtuvieron 0,86 ± 0,33% células CD34+. Se analizan las indicaciones y resultado de trasplantes de médula ósea y de sangre de cordón en diferentes patologías. Hasta ahora no existe indicación médica para el uso de células madres autólogas de sangre de cordón en leucemias infantiles, ni en enfermedades genéticas. En infarto del miocardio no se han obtenido resultados satisfactorios con los protocolos clínicos evaluados, mientras que en daño neurológico, el uso de células madres permanece todavía como una aproximación experimental.

Hematopoietic stem cells are undifferentiated cells with high proliferative rate and autorenovation; they are found in bone marrow (1%-3%) and blood (0.1%), being identified by the expression of the marker CD34. They may be mobilized from bone marrow (B.M.) into the blood after chemotherapy or cytokine treatment. In this study, stem cells were identified in fetal and adult blood. Two hundred and seventy eigh blood samples were analyzed; they were obtained from fetuses (17-32 weeks-old), neonates, and in the products from apheresis performed to patients with malignancies. The amount of CD34+ cells decreased as the gestational age increased (6.10% to 1.03%). These cells grew in culture to produce granulocytic and erytrocytic colonies. In cord blood CD34+ cell were identified (0,86% ± 0,33%). Indications and results of bone marrow and cord blood stem cell transplants in different pathologies are analyzed. The transplant of allogeneic cord blood stem cells in patients not having a compatible donor is the worldwide approved indication for this procedure. No satisfactory results has been obtained in cases of myocardial infarct. The treatment of neurological damage remains experimental.

Células progenitoras hematopoyéticas de sangre de cordón umbilical / Hematopoietic progenitor cells from umbilical cord blood

La sangre de cordón umbilical (SCU) es una rica fuente de células progenitoras hematopoyéticas (CPH) para el trasplante. Se describe la historia del uso de la SCU para trasplante hematopoyético y la necesidad del consentimiento informado para su obtención, conservación, almacenamiento y uso con estos fines. Se hace referencia a la seguridad para el receptor en cuanto a selección, requisitos epidemiológicos, obstétricos y analíticos de la muestra, la calidad hematopoyética de la colecta y procesamiento hasta su conservación, así como a las ventajas y desventajas de su uso en el trasplante. Por último, se aborda la importancia de incrementar en los bancos de SCU, el almacenamiento de CPH que tengan representación antigénica compatible con las minorías étnicas

The umbilical cord blood (UCB) is a rich source of hematopoietic progenitor cells (HPC) for transplantation. Here, we describe the history of using of UCB for hematopoietic transplantation and the need of obtaining informed consent for its conservation, storage and further use for these purposes. Reference is made to the security for the receiver in terms of sample selection, epidemiological, obstetrical, and analytical requirements, as well as the quality of hematopoietic collection and processing for preservation, in addition to the advantages and disadvantages of its use in transplantation. Finally, we address the importance of increasing the UCB banks, storing CPH with antigenic representation compatible with ethnic minorities

O intervalo de tempo entre coleta e processamento do sangue de cordão umbilical influencia na qualidade da amostra? / Does the time between collecting and processing umbilical cord bloodsamples affect the quality of the sample?

Objective: To assess the association between the time from umbilical cord blood collection until processing and the quality of the sample. Methods: Umbilical cord blood samples collected during the third stage of labor were placed in temperature-controlled boxes for the transport of biological material and sent to an umbilical cord blood bank, where the number of nucleated cells, viable cells and CD34+ cells were counted, and samples were additionally tested for contamination at the following time intervals: up to 24 hours, up to 48 hours and up to 72 hours following sampling. Data were analyzed using the multivariate analysis of variance (MANOVA) and compared using McNemar's X2 test. Significance was defined at p < 0.05. Results: Means and medians of the number of nucleated cells, viable cells and CD34+ cells decreased significantly (p < 0.0001) as a function of the increased time between sampling and analysis, the difference between 24 and 48 hours being less than the difference between 24 and 72 hours. A linear correlation was found between the mean number of viable cells and CD34+ cells at the three moments of analysis. Contamination testing was negative in all samples. Conclusion: The increase in time interval from sampling until analysis negatively affected the number of nucleated cells, viable cells and CD34+ cells but was not associated with specimen contamination. A linear correlation was found between decrease in the number of viable cells and CD34+ cells.

Objetivo: Avaliar a associação do intervalo de tempo entre coleta e processamento do sangue de cordão umbilical e a qualidade da amostra. Métodos: As amostras de sangue de cordão umbilical, colhidas no terceiro período do parto, foram acondicionadas em caixas homologadas para transporte de material biológico, com monitoração da temperatura, e enviadas a um banco de sangue de cordão umbilical, onde foram submetidas à contagem do número de células nucleadas, do número de células viáveis, do número de células CD 34+ e pesquisa de contaminação, nos intervalos de tempo de até 24, até 48 e até 72 horas. Os dados foram analisados pelo teste de variância para medidas repetidas MANOVA e comparados por meio do teste do X2 de Mc Nemar, considerando-se nível de significância de 5%. Resultados: As médias e as medianas do número de células nucleadas, número de células viáveis e número de células CD34+ tiveram quedas significativas (p < 0,0001) com o aumento do intervalo de tempo de coleta/processamento, sendo entre 24 e 48 horas menor do que a comparação entre 24 e 72 horas. Constatada correlação linear entre as médias de células viáveis e células CD34+ nos três momentos da análise. A pesquisa de contaminação foi negativa em todas as amostras. Conclusão: O aumento do intervalo de tempo de coleta/processamento influenciou negativamente na contagem de células nucleadas, células viáveis e CD34+ e não esteve associado à contaminação das amostras. Foi constatada correlação linear entre a queda do número de células viáveis e de células CD34+.

Hematopoietic Stem Cell Transplantation in Children with Leukemia: A Single Institution Experience with Respect to Donors

Aim of this study was to compare the outcomes of transplantation by donor source and to help select the best alternative donor in children with leukemia. Donor sources included matched related donor (MRD, n = 35), allele-matched unrelated donor (M-UD, n = 10) or -mismatched (MM)-UD (n = 13) or unrelated umbilical cord blood (UCB, n = 11). UCB group had a significantly higher incidence of grade II-IV acute graft versus host disease (MRD, 11.8%; M-UD, 30.0%; MM-UD, 15.4%, UCB, 54.4%, P = 0.004) but there was no difference in incidence of chronic graft versus host disease between 4 groups. The 5-yr leukemia-free survival (LFS) was 76.7%, 60.0%, 69.2%, and 45.5%, respectively (P = 0.128). MRD group showed higher LFS rate than UCB group (P = 0.022). However, LFS of M-UD and MM-UD together (65.2%) was not different from that of MRD group (76.7%, P = 0.325), or from that of UCB (45.5%, P = 0.190). The relapse incidence at 5 yr was 17.1%, 20.0%, 15.4%, and 0%, respectively (P = 0.460). The 100-day treatment-related mortality was 2.9%, 20.0%, 7.7%, and 36.4%, respectively (P = 0.011). Despite the limitations of small number of patients, unrelated donor transplants including even allele-mismatched ones, seem to be as effective in children with leukemia lacking suitable relative donors. Also, UCB transplant may serve as another possible option in urgent transplants.

Existem evidências que justifiquem o congelamento do próprio cordão umbilical? / Is there evidence that justifies freezing our own umbilical cord?

O transplante de células progenitoras hematopoéticas é um procedimento eficaz para o tratamento de doenças hematológicas malignas ou não malignas, distúrbios imunológicos e metabólicos. Entre as fontes conhecidas de células progenitoras hematopoéticas, o sangue de cordão umbilical e placentário tem se destacado, cada vez mais, como fonte segura. É amplamente empregado na realização de transplantes em pacientes que não possuem doadores HLA compatíveis entre os familiares ou em registros de doadores de medula. O sangue de cordão pode ser utilizado em transplantes alogênicos, autólogos ou alogênicos apresentados. Existe uma grande controvérsia quanto à utilidade e à probabilidade da utilização autóloga de sangue de cordão umbilical e placentário. Nesta revisão, discutimos os principais aspectos do processo de armazenamento e a relevância clínica do sangue de cordão umbilical, assim como as questões controversas em relação ao seu emprego autólogo.

Hematopoietic progenitor cell transplantation is an effective procedure for the treatment of malignant or non-malignant hematologic diseases, immune and metabolic disorders. Among the known sources of hematopoietic progenitor cells, cord blood has increasingly emerged as a reliable one, and is widely used to perform transplantations in patients who have no HLA compatible donors among relatives or bone marrow donor's registries. Cord blood can be used in allogeneic, autologous or related allogeneic transplantations. There is great controversy regarding the usefulness and therapeutic effect of using autologous cord blood. In this review we discuss the main aspects of collection, cryopreservation and clinical utility of umbilical cord blood, as well as issues regarding its autologous use.

Artículos de revisión: cultivos de expansión ex vivo de células madre a partir de sangre de cordón umbilical / Reviews: hematopoietic stem cell, ex vivo expansion from umbilical cordon blood

El éxito en el enfrentamiento a las hemopatías malignas depende de la erradicación de los clones tumorales por medio de la quimioterapia y la radioterapia. Sin embargo, en determinados pacientes la capacidad de curación se muestra limitada, y se requiere la sustitución de la función medular dañada por una nueva hematopoyesis sana, a través del trasplante de médula ósea (TMO). Este tipo de terapia celular puede contar ahora con donantes alternativos obtenidos a partir de la sangre de cordón umbilical (SCU) almacenada en bancos creados en varios países. Se ha comprobado la necesidad de promover un implante más rápido que disminuya la morbimortalidad relacionada con el procedimiento y permita la generalización de su uso, y se han propuesto estrategias basadas en la expansión de las células progenitoras hematopoyéticos (CPH) ex vivo, en cultivos a partir de SCU, lo que permite su uso en trasplantes con bajo contenido celular, y para diferenciar células pertenecientes a diferentes linajes hematopoyéticos, e incluso tejidos, con diferentes objetivos: trasplante hematopoyético, soporte de la recuperación a corto plazo, inmunoterapia, terapia génica, y diferenciación a tejidos mesenquimales. En esta revisión se explica cómo, de un producto habitualmente desechado, la SCU se ha convertido en una fuente de gran interés científico por la facilidad de su colecta, la fuente "ilimitada" de donantes, la calidad biológica de sus células madre cercanas a la época embrionaria y fetal del desarrollo, y la posibilidad de un uso amplio en diferentes estrategias de expansión ex vivo para terapia celular.

Comparação entre as células-tronco de sangue de cordão umbilical de neonatos prematuros e nascidos a termo: uma revisão / Comparison between preterm and full-term newborn umbilical cord blood stem cells: a review

As células-tronco são células capazes de gerar diferentes tipos celulares. Entre as fontes de células-tronco encontra-se osangue de cordão umbilical que apresenta um grande número de progenitores hematopoéticos. Essa fonte vem sendo amplamente utilizada em transplantes devido a diversas vantagens, entre elas, a imediata disponibilidade, beneficiando pacientes com doenças hematológicas e imunológicas. Para o sucesso dos transplantes, há a necessidade de se considerar a freqüência das células-tronco nas amostras de sangue de cordão umbilical. Marcadores celulares específicos como a presença da molécula CD34 e a ausência de CD38 indicam o grau de imaturidade das células-tronco hematopoéticas e, conseqüentemente, a sua grande capacidade de proliferação e diferenciação celular. Existem diferenças quanto à freqüência das células-tronco no sangue de cordão umbilical entre neonatos nascidos a termo e prematuros. Essas diferenças podem ser importantes na escolha das amostras armazenadas nos bancos de sangue de cordão umbilical a serem utilizadas nos transplantes de células-tronco. Além disso, as pesquisas com células-tronco têm mostrado grande capacidade de proliferação e diferenciação em vários tecidos. O estudo das células-tronco pode ser a resposta para o tratamento de doenças cardíacas, neurológicas e imunológicas de inúmeros pacientes e, talvez, o primeiro passo para a cura.

Stem cells are cells that have the ability to give rise to different cell types. Among the sources of stem cells, there is the umbilical cord blood, which has a great number of hematopoietc progenitors. This source has been widely used in transplants owingto its advantages like, for example, immediate availability, improving patients with immunological and hematological diseases. In order for the transplant to be successful, it is necessary to consider the stem cell frequency within the samples of the umbilical cord blood. Specific markers like the presence of CD34 molecule and the absence of CD38 indicates the immature level of hematopoietic stemcells and consequently their ability of cellular proliferation and differentiation. There are differences between the cellular frequency in umbilical cord blood from preterm and term newborn. These differences might be important in order for finding a sample stored atumbilical cord blood banks for the transplant. Nevertheless, research using stem cells has attempted that these cells have a great capacity of proliferation and differentiatin into many tissues. Stem cell research offers hope for the treatment of cardiac, neurological and imunological diseases of countless patients and, perhaps, the first step to the cure.

Banco público de sangre de cordón umbilical / A public cord blood bank. Programs for related and unrelated transplantation

La sangre de cordón umbilical (SCU) ofrece una fuente rica de células progenitoras hematopoyéticas para trasplante de médula ósea (TMO). En el año 1996 comenzó en nuestro Hospital un programa relacionado de Banco De SCU. Este programa permite que familias con un niño que padece una enfermedad tratable con TMO almacene la SCU de un hermano por nacer para su futuro uso. En este tabajo presentamos nuestra experiencia de más de 8 años. Uno de nuestros objetivos ha sido comparar retrospectivamente carecterísticas de los donantes y unidades de SCU según el tipo de parto (vaginal Vs. cesárea). Desde marzo de 1996 hasta noviembre de 2004 se inscribieron 106 familias. Características de las unidades: volumen colectado 113 más o menos 36 ml; volumen preservado 76 más menos 28 ml; células nucleadas totales 10 más menos 5 por 108 cél.; células CD34 más 2,41 más menos 2,31 por 106 cél. La dosis de células nucleadas fue mayor a 2 por 107 por Kg. de receptor para el 93 por ciento de las unidades almacenadas. Las colectas provenientes de partos por cesárea no difieren significativamente de los partos vaginales. Recientemente, el programa no relacionado ha sido aprobado y recibió apoyo financiero del Ministerio de Salud de la Nación para adquirir nuevo equipamiento. Este programa tiene como objetivo colectar y preservar unidades de SCU donadas de manera altruista, que quedan disponibles para su uso en TMO alogeneicos en pacientes que no poseen otro donante compatible. El funcionamiento de este Banco nos permitirá aumentar la oferta internacional de unidades con perfil HLA latinoamericano hispano, escaso en los registros existentes en la actualidad.