Agreements and uncertainties in autologous haematopoietic stem cell mobilization and collection. A Spanish consensus document.

Although many experts position statements on autologous stem cell mobilization have been published, there are some aspects that are still under discussion. A Spanish Hematologist expert group was summoned to settle on agreements and uncertainties on PBSCs mobilization, including factors not always considered; as apheresis and cytometry key factors that determine a successful PBSC collection. This document reviews critical factors that define poor mobilizer patients and the tools to better collect the desired stem cells for a successful autologous haematopoietic stem cell transplant.

Mobilization of peripheral blood stem cells with plerixafor in poor mobilizer patients

"BACKGROUND AND OBJECTIVE: Poor mobilization of peripheral blood stem cells (CD34(+) cells) from bone marrow is a frequent reason for not reaching the autologous stem cell trasplantation (SCT) procedure in patients diagnosed with lymphoma or myeloma. Plerixafor, a reversible inhibitor of the binding of stromal cell-derived factor 1 to its cognate receptor CXCR4, has demonstrated a higher capacity for the mobilization of peripheral blood stem cells in combination with granulocyte colony stimulating factor (G-CSF) compared with G-CSF alone. For this reason, plerixafor is now indicated for poor mobilizer myeloma or lymphoma patients. Some studies have recently indicated that a pre-emptive strategy of plerixafor use during first mobilization, according to the number of CD34(+) mobilized cells in peripheral blood or to the harvested CD34(+) cells after first apheresis, could avoid mobilization failures and re-mobilizations, as well as the delay of autologous SCT. The aim of this consensus was to perform a review of published studies on pre-emptive strategy and to establish common recommendations for hospitals in Catalonia and Balearics on the use of pre-emptive plerixafor. METHODS: For the Consensus, physicians from participant hospitals met to review previous studies as well as previous own data about plerixafor use. The GRADE system was used to qualify the available evidence and to establish recommendations on the use of pre-emptive plerixafor. RESULTS AND CONCLUSIONS: After a review of the literature, the expert consensus recommended the administration of pre-emptive plerixafor for multiple myeloma or lymphoma patients with a CD34+ cell count lower than 10 cells/µL in peripheral blood (measured in the morning of day 4 of mobilization with G-CSF or after haematopietic recovery in the case of mobilization with chemotherapy plus G-CSF)."

"Fundamento y objetivo El fracaso de movilización de progenitores hematopoyéticos a sangre periférica (células CD34+) desde el compartimento medular es una causa frecuente de no realización de trasplante autogénico de progenitores hematopoyéticos (TAPH) en pacientes con linfoma o mieloma. Plerixafor, un inhibidor reversible de la unión del factor derivado del estroma 1 con su receptor CXCR4, ha demostrado mayor movilización de progenitores hematopoyéticos cuando se administra junto con granulocyte colony stimulating factor (G-CSF, «factor estimulante de colonias granulocíticas¼), respecto a la movilización con G-CSF solo, por lo que en la actualidad está indicado en pacientes con mieloma o linfoma y escasa capacidad de movilización. En los últimos años algunos estudios han señalado que una estrategia de administración anticipada de plerixafor durante la primera movilización, basada en el número de células CD34+ movilizadas a sangre periférica o en la celularidad obtenida en la primera aféresis, podría evitar fracasos de movilización y nuevas movilizaciones, así como el retraso del ulterior trasplante. El objetivo del presente consenso fue realizar una revisión de la bibliografía y establecer unas recomendaciones comunes para hospitales de Cataluña y Baleares para la utilización de una estrategia de administración anticipada de plerixafor. Métodos Para la elaboración del documento de consenso se realizaron reuniones presenciales en las que se realizó una revisión de la bibliografía y de datos propios procedentes de los hospitales participantes. Para calificar el grado de la evidencia disponible y establecer las recomendaciones de uso anticipado de plerixafor se ha utilizado el sistema GRADE. Resultados y conclusiones Tras la revisión de la bibliografía, el consenso de expertos definió que con un recuento inferior a 10 células CD34+/µl en sangre periférica (determinado en la mañana del día cuarto de la movilización con G-CSF solo o en el día de la recuperación hemoperiférica tras la movilización con quimioterapia seguida de G-CSF) se recomienda la administración anticipada de plerixafor."

Responsabilidad profesional médica en embarazo posvasectomía / Medical professional responsibility for postvasectomy pregnancy

Introducción: El seguimiento de los pacientes posvasectomía queda frecuentemente limitado a un seminograma a los 3 meses si se objetiva azoospermia. Este trabajo evalúa una serie de casos de reclamaciones por embarazo posvasectomía, con el objetivo de establecer recomendaciones de seguimiento que aumenten la seguridad clínica y disminuyan el riesgo de reclamaciones. Material y métodos: Se revisó la base de datos del Servicio de Responsabilidad Profesional del Consejo del Colegio de Médicos de Cataluña, localizándose 28 reclamaciones por embarazo posvasectomía entre 1992 y 2011. Se analizaron las variables clínicas y jurídicas de los casos. Resultados: Se registraron 13 reclamaciones extrajudiciales (46,43%), 13 demandas civiles (46,43%) y 2 penales (7,14%). Únicamente en 10 casos constaba la firma de un documento de consentimiento informado específico para vasectomías. En 26 casos se dispuso de los datos correspondientes al espermiograma. En 20 casos (76,92%) se realizó un único espermiograma, en 4 se realizaron 2 (15,38%) y en 2 casos no se realizó ninguno (7,69%). Cuando solo se llevó a cabo un único espermiograma, en 9 casos (45%) este se realizó antes de los 3 meses. En 17 casos (65,38%) el resultado del último espermiograma fue de azoospermia, 3 casos de oligospermia (11,54%), hubo 2 fallos de interpretación del espermiograma (7,69%), 2 de normospermia (7,69%) y en 2 casos no se realizó espermiograma (7,69%). El embarazo se produjo entre los 4 y los 50 meses de la intervención. En 12 casos (42,86%) se consideró que existía responsabilidad profesional. Discusión: Se recomienda enfatizar en la información al paciente la posibilidad de la recanalización espontánea y solicitar 2 espermiogramas con resultado de azoospermia, resultando de riesgo su realización antes de los 3 meses o basar el tiempo de espera en un número de eyaculaciones

Background: The follow-up of patients postvasectomy is frequently limited to a seminogram at 3 months if azoospermia is observed. This study evaluates a series of cases of complaints for postvasectomy pregnancy to establish follow-up recommendations that increase the clinical safety and reduce the risk of complaints. Material and methods: We reviewed the database of the Department of Professional Responsibility of the Council of the College of Physicians of Catalonia, finding 28 complaints for postvasectomy pregnancy between 1992 and 2011. We analysed the clinical and legal variables of the cases. Results: A total of 13 extrajudicial complaints (46.43%), 13 civil lawsuits (46.43%) and 2 criminal lawsuits (7.14%) were recorded. Only 10 cases had a signed document of informed consent specific to vasectomy. In 26 cases, the data from the spermogram was available. A single spermogram was conducted in 20 cases (76.92%), 2 spermograms were conducted in 4 cases (15.38%) and none were performed in 2 cases (7.69%). For 9 of the cases (45%) where only a single spermogram was performed, the test was performed before 3 months postvasectomy. In 17 cases (65.38%), the result of the last spermogram was azoospermia, and 3 cases had oligospermia (11.54%). There were 2 failures of interpretation of the spermogram (7.69%) and 2 of normospermia (7.69%). In 2 cases, a spermogram was not performed (7.69%). Pregnancy occurred between 4 and 50 months after the intervention. In 12 cases (42.86%), it was considered that the practitioner was responsible. Discussion: It is recommended that physicians emphasise (during the patient information stage) the possibility of spontaneous recanalisation and to request 2 spermograms, whose result should be azoospermia. Performing the test in the 3 months after vasectomy is risky, as is basing the waiting time on the number of ejaculations

Medical professional responsibility for postvasectomy pregnancy. / Responsabilidad profesional médica en embarazo posvasectomía.

BACKGROUND: The follow-up of patients postvasectomy is frequently limited to a seminogram at 3months if azoospermia is observed. This study evaluates a series of cases of complaints for postvasectomy pregnancy to establish follow-up recommendations that increase the clinical safety and reduce the risk of complaints. MATERIAL AND METHODS: We reviewed the database of the Department of Professional Responsibility of the Council of the College of Physicians of Catalonia, finding 28 complaints for postvasectomy pregnancy between 1992 and 2011. We analysed the clinical and legal variables of the cases. RESULTS: A total of 13 extrajudicial complaints (46.43%), 13 civil lawsuits (46.43%) and 2 criminal lawsuits (7.14%) were recorded. Only 10 cases had a signed document of informed consent specific to vasectomy. In 26 cases, the data from the spermogram was available. A single spermogram was conducted in 20 cases (76.92%), 2 spermograms were conducted in 4 cases (15.38%) and none were performed in 2 cases (7.69%). For 9 of the cases (45%) where only a single spermogram was performed, the test was performed before 3months postvasectomy. In 17 cases (65.38%), the result of the last spermogram was azoospermia, and 3 cases had oligospermia (11.54%). There were 2 failures of interpretation of the spermogram (7.69%) and 2 of normospermia (7.69%). In 2 cases, a spermogram was not performed (7.69%). Pregnancy occurred between 4 and 50 months after the intervention. In 12 cases (42.86%), it was considered that the practitioner was responsible. DISCUSSION: It is recommended that physicians emphasise (during the patient information stage) the possibility of spontaneous recanalisation and to request 2 spermograms, whose result should be azoospermia. Performing the test in the 3months after vasectomy is risky, as is basing the waiting time on the number of ejaculations.

Assessing the toxic effects of DMSO on cord blood to determine exposure time limits and the optimum concentration for cryopreservation.

BACKGROUND AND OBJECTIVES: Advantages of using cord blood (CB) over other sources of haematopoietic progenitor cells, such as bone marrow, include the ability to cryopreserve and bank the samples until requested for a transplant. Cryopreservation requires the addition of a cryoprotectant to prevent the formation of intracellular ice during freezing. Dimethyl sulphoxide (DMSO) is commonly used at a concentration of 10% (v/v); however, there is evidence to suggest this chemical is toxic to cells as well as to patients after infusion. MATERIALS AND METHODS: The toxic effects of DMSO were assessed through cell viability and in vitro functional assays in fresh and post-thaw CB samples before determining the maximum exposure time and optimal concentration for cryopreservation. RESULTS: A dose-dependent toxicity of DMSO was observed in fresh samples with 40% removing all viable and functional haematopoietic progenitor cells (HPC). In fresh and post-thaw analysis, minimal toxic effect was observed when cryopreservation was delayed for up to 1 h after 10% DMSO addition. After thawing, DMSO washout was superior to dilution or unmanipulated when maintained for long periods (advantage observed 1 h after thawing). Finally, the optimum concentration for cryopreserving CB was found to be 7.5 to 10% with detrimental effects observed outside of this range. CONCLUSION: These results support the use of 7.5-10% as the optimal DMSO concentration and the maximum exposure time should be limited to <1 h prior to freezing and 30 min post-thaw.

Plerixafor in patients with lymphoma and multiple myeloma: effectiveness in cases with very low circulating CD34+ cell levels and preemptive intervention vs remobilization.

This retrospective study presents data from 105 consecutive multiple myeloma and lymphoma patients who had PB CD34+ cell counts <10/µL on day 4 of steady-state G-CSF mobilization for autologous hematopoietic cell transplantation. Our results confirm the capacity of plerixafor to improve mobilization outcomes in this clinical setting. In addition, they show that the effectiveness of plerixafor, compared with G-CSF only, translates to patients with very low (<3.5/µL) circulating CD34+ cell counts: overnight CD34+ cell count expansion (5.3- vs 1.7-fold), overall CD34+ cell yield (2.29 vs 0.15 × 10(6) CD34+ cells per kg) and patients yielding ⩾2 × 10(6) CD34+ cells per kg (63% vs 3%). Furthermore, our data also show that preemptive plerixafor is significantly more effective and more efficient than in remobilization: CD34+ cell yield in the first apheresis (3.28 vs 2.0 × 10(6) CD34+ cells per kg) and overall (3.73 vs 2.44 × 10(6) CD34+ cells per kg), patients yielding ⩾2 × 10(6) CD34+ cells per kg in the first apheresis (85% vs 44%) and overall (92% vs 64%), all this requiring less days and doses of plerixafor treatment (1.08 vs 1.48). These data would advocate using plerixafor as an early preemptive intervention based on day 4 circulating CD34+ counts, including very high-risk patients with very low circulating levels.

Quality rather than quantity: the cord blood bank dilemma.

Growing inventories of cord blood units have facilitated access to umbilical cord cell transplantation for many patients lacking conventional stem cell donors. They are in principle 'off-the-shelf', 'fit-for-use', as well as safe and effective therapy products. Cellular enumeration is used as a surrogate of graft potency, and users rely on the rigorous assessment carried out in banks to avoid poor engraftment after thawing (loss of cells or poor function), when the patient's situation is critical. However, in practice, when units are selected, initially on the basis of HLA matching and cell dose assessment, their absolute quality remains uncertain. Unfortunately, quality-related issues (particularly related to viability) are not uncommon in cord blood transplantation. The reasons for potency failures are diverse, but a lack of thorough validation during critical steps of the process and of appropriate use of quality-control tools for timely detection of problematic units are significant contributors. Moreover, incongruence between different sets of standards and regulations, and lack of common quality systems between banks result in a highly heterogeneous international inventory. Therefore, this complicates the matter for the end user of the product. To ameliorate this situation, it is essential to improve quality at each of the critical manufacturing steps wherein potency can be threatened, thereby creating homogeneous inventories of units with excellent quality and quantity.

Recommendations for a standard UK approach to incorporating umbilical cord blood into clinical transplantation practice: conditioning protocols and donor selection algorithms.

Allogeneic haematopoietic cell transplantation is an established curative treatment modality for patients with malignant and non-malignant haematological disorders. Since the first related umbilical cord blood transplant (UCBT) in 1988, the use of UCB as a stem cell source for transplantation has become a standard practice in many countries, with approximately 8000 such transplants having been performed worldwide to date.

Factors modulating circulation of hematopoietic progenitor cells in cord blood and neonates.

BACKGROUND: Hematopoietic progenitor cells (HPC) circulate at high levels at birth and disappear rapidly afterwards, but the underlying mechanism it is not known. The aim of this study was to assess circulating HPC in cord blood at different gestational ages and shortly after birth and concomitantly study the biologic markers involved in this phenomenon. METHODS: All samples were analyzed for CD34(+) cells, colony-forming units (CFU) and cytokines. RESULTS: The results obtained confirmed a slight decrease in HPC concentration during the late stage of fetal life (R(2)=0.41). After birth, CD34(+) cells showed a rapid decline from circulation: 25+/-29% at 3 h, 51+/-42% at 12 h and 80+/-48% at 60 h. CFU cleared following a similar pattern. Cord plasma showed higher concentrations of stem cell factor (SCF), fetal liver tyrosine kinase 3-ligand (FLT3l), erythrpoietin (EPO), granulocyte colony-stimulating factor (G-CSF) and interleukin-11 (IL-11) compared with an adult control. Interestingly, the EPO concentration in newborn plasma correlated with the kinetics of HPC decline after birth. Moreover, we observed an up-regulation of l-selectin and a down-regulation of CXCR4 expression in CD34(+) cells 3 h after birth. DISCUSSION: These data combined suggest that an active homing process results in the clearance of HPC from the circulation immediately after birth.

[Embryonal rhabdomyosarcoma of spermatic cord and prostatic adenocarcinoma. Case report and review of the literature]. / Rabdomiosarcoma embrionario del cordón espermático asociado a adenocarcinoma prostatico. Presentación de un caso y revisión de la literatura.

We present a tumor developed from spermatic cord structures. The histology (rhabdomyosarcoma), the age of the patient and its association with a prostatic adenocarcinoma has developed this case report. Histopathological singularity and regional treatment choice are the two key points of this case.

Rabdomiosarcoma embrionario del cordón espermático asociado a adenocarcinoma prostatico. Presentación de un caso y revisión de la literatura / Embryonal rhabdomyosarcoma of spermatic cord and prostatic adenocarcinoma. Case report and review of the literature

Presentamos el caso de una tumoración derivada de estructuras del cordón espermático. La histología (rabdomiosarcoma), la edad de presentación (adulta) y la asociación con un cáncer de próstata motivó esta nota clínica. La especificidad del estudio anatomopatológico e inmunohistoquímico y el planteamiento del tratamiento regional son los dos aspectos claves del caso (AU)

We present a tumor developed from spermatic cord structures. The histology (rhabdomyosarcoma), the age of the patient and its association with a prostatic adenocarcinoma has developed this case report. Histopathological singularity and regional treatment choice are the two key points of this case (AU)

Ex vivo expansion of umbilical cord blood CD34 cells in a closed system: a multicentric study.

BACKGROUND AND OBJECTIVES: The Dideco 'Pluricell System' is a CE-marked medical device allowing haematopoietic stem cell (HSC) expansion. It comprises a kit of cGMP cytokines and reagents, a closed-cell expansion chamber and a cell-washing set. We tested the system in a multicentric study by expanding CD34(+) cells from eight fresh umbilical cord blood (UCB) samples. MATERIALS AND METHODS: During culture, the mean nucleated cell (NC) count, the mean CD34(+) cell count, fold expansion, viability and apoptosis were measured. Clonogenic assays and immunophenotypical characterization were performed on days 0, 7 and 12. On the expanded cellular product, in three cases cell genotyping, endotoxin level and mycoplasma detection (by polymerase chain reaction) were performed. RESULTS: The mean CD34(+) cell expansion on days 7 and 12 was sevenfold and 12-fold respectively and the mean NC expansion was 69-fold and 180-fold. The mean NC viability on day 12 was 96.9% (94.4-99.1). After 12 days, granulocyte-macrophage colony-forming units (GM-CFU) showed a 20-fold increase: a slight increase in CD34(+) cell apoptosis was observed during culture. In all of three cases neither chromosomal alterations nor mycoplasma contamination was detected. No significant endotoxin levels were detected after expansion. CONCLUSIONS: The device allows the ex vivo expansion of NC and CD34(+) cells in a closed system. The expanded cellular product is a mixture of progenitors (CD34(+) cells) and differentiated (mainly myeloid and megakaryocytic) cells. To reduce cell apoptosis, more frequent cell feeding during culture should be tested.

[Sudden anuria secondary to migration of aortic stent in a single kidney patient]. / Anuria súbita en paciente monorreno secundaria a migración de endoprótesis aórtica.

Percutaneous acces to manage infrarenal aortic aneurysm is a less aggressive technique, but it's not entirely risk free. The migration of stents isn't a frequent complication in that percutaneous technique. Urgent left renal revascularition, when anterior approach or autologous transplantation is not possible, is feasibily by a splenorenal shunt through a lumbar approach.

Anuria súbita en paciente monorreno secundaria a migración de endoprótesis aórtica / Sudden anuria secondary to migration of aortic stent in a single kidney patient

El manejo percutáneo de los aneurismas de aorta infrarrenal es una técnica menos agresiva, pero no está exenta de riesgos. La migración craneal de las endoprótesis es un proceso infrecuente en dicha técnica. Ante una revascularización renal izquierda de urgencia en que no se pueda tener acceso a una vía anterior o la posibilidad de un autotrasplante, una buena alternativa es la realización de unshunt esplenorrenal mediante un acceso lumbar (AU)

Percutaneous acces to manage infrarenal aortic aneurysm is a less aggressive technique, but it’s not entirely risk free. The migration of stents isn’t a frequent complication in that percutaneous technique. Urgent left renal revascularition, when anterior approach or autologous transplantation is not possible, is feasibily by a splenorenal shunt through a lumbar approach (AU)

Washing of cord blood grafts after thawing: high cell recovery using an automated and closed system.

BACKGROUND AND OBJECTIVES: Cord blood (CB) progenitor cells are an alternative source of haematopoietic stem cells for bone marrow reconstitution. The critical importance of cell dose in the clinical outcome has motivated the need to develop techniques aimed at reducing cell losses and increasing reproducibility. This aim of this study was to evaluate an automated CB washing protocol of thawed cord blood units using the Sepax device. MATERIALS AND METHODS: After an initial 1:1 dilution using a dextran/albumin-containing buffer, the cells were washed in order to obtain a final product ready for transplantation. The automatic method was compared with the conventional manual washing procedure. Blood samples were taken after thawing and after washing. The processing time, viability and mean recovery of nucleated cells (TNC) and progenitors were determined. RESULTS: The automatic procedure resulted in a median recovery of 93% CD34+ cells and 89% TNC; no significant differences were observed between methods. In addition, median viability, as assessed by annexin V and 7-aminoactinomycin D (7-AAD), was 98% and 94%, respectively, within CD34+ cells. CONCLUSIONS: The automatic washing method described is as effective as the manual method in terms of viability and progenitor cells recovery, but faster and easier for the operators to perform. Overall, our data suggest that the automatic method is safe and suitable for the routine washing of thawed CB grafts in the clinic.

DRB1*1446 allele variations in the group-specific annealing sites of common amplification primers.

A cord blood unit from the Umbilical Cord Bank of Barcelona was initially typed by sequence-based typing (SBT) as DRB1* 0701. However, the subsequent confirmation by sequence-specific oligonucleotide probes (SSOP) revealed an unusual hybridization pattern that did not fit any of the known HLA-DRB1 alleles or allelic combinations. Molecular cloning and sequencing with primers located at introns 1 and 2 provided the definitive identification of a novel DRB1*1446 allele. It was similar to DRB1*1402 at exon 2 except for nucleotide substitutions at codons 10, 11 and 12 (from YST to LRK) that coincide with the 5'-end group specific site for the annealing of common amplification primers used by SBT and sequence-specific primers.

Sequence of the HLA-B*1573 allele.

We report here the sequence of an HLA B*15 allele, B*1573. Initially, a cord blood unit from the Umbilical Cord Bank of Barcelona was typed by sequence-specific oligonucleotide hybridization and revealed an unusual hybridization pattern. After the cloning, the sequence-based typing assigned two different alleles: B*07021, and a second allele identical to B*1558 in exons 2 and 3, except for a single nucleotide substitution in exon 3, which changed codon 140 from Phe to Leu (TTX-->TTA).

Combined isolation of CD34+ progenitor cells and reduction of B cells from peripheral blood by use of immunomagnetic methods.

BACKGROUND: Malignant cells may contribute to relapse after autologous hematopoietic cell transplantation The effectiveness of a double immunomagnetic purging strategy combining CD34-positive with B-negative cell selection to purge peripheral blood progenitor cells (PBPCs) from patients with chronic lymphoproliferative disorders has been analyzed. STUDY DESIGN AND METHODS: Twenty-two CD34+ cell selections from patients with follicular lymphoma (n = 14), chronic lymphocytic leukemia (n = 6), mantle cell lymphoma (n = 1), and splenic marginal zone lymphoma (n = 1) were performed by use of a magnetic cell selector followed by a negative cell selection step with anti-CD19 monoclonal antibody bound to immunomagnetic beads. RESULTS: The PBPC components contained median CD34+ cells of 1.24 percent (range, 0.38-3.92%) and CD19+ cells of 1.83 percent (range, 0.06-69.7%). After positive selection (n = 22), 49 percent (range, 16-72%) of CD34+ cells were recovered with a purity of 93 percent (range, 24-99%). The double-positive and -negative selections (n = 20) yielded 57.5 percent of CD34+ cells (range, 33.4-79.4%) with a purity of 95 percent (range, 63-99%). Logarithms of B-cell reduction in the CD34+-cell-enriched B-cell-depleted component had a median value of 3.63 (range, 2.74-4.84 log) and CD19+ and CD5+ cells for chronic lymphocytic leukemia patients with more than 4.56 log (>3.6-5.6 log). Of 13 PBPC components that had a tumor-specific clonal signal, 10 became PCR negative after the double-selection procedure. CONCLUSION: Combined positive and negative magnetic cell selection achieves a high grade of tumor cell reduction with up to 77 percent of the grafts being negative for tumor-specific clonal signal by PCR analysis. This technique preserves an adequate recovery of progenitor cells able to engraft.