Spontaneous rupture of spleen during peripheral blood stem-cell mobilisation in a healthy donor

Splenic rupture following lenograstim in post-autologous stem cell transplantation treated with emergency open splenectomy: a case report and literature review

Granulocyte-colony stimulating factors (G-CSFs) are the cornerstone of peripheral blood stem cell mobilization and apheresis. However, splenic rupture following G-CSF treatment represents a serious and potentially fatal adverse event. Here, we report the case of a patient in their late 50s with severe pancytopenia post-autologous stem cell transplantation reinfusion suffering from splenic rupture after treatment with lenograstim. We also reviewed the literature describing cases of splenic rupture during G-CSF administration.

Hematopoietic Stem Cell Mobilization: Current Collection Approaches, Stem Cell Heterogeneity, and a Proposed New Method for Stem Cell Transplant Conditioning

Hematopoietic stem cells naturally traffic out of their bone marrow niches into the peripheral blood. This natural trafficking process can be enhanced with numerous pharmacologic agents - a process termed "mobilization" - and the mobilized stem cells can be collected for transplantation. We review the current state of mobilization with an update on recent clinical trials and new biologic mechanisms regulating stem cell trafficking. We propose that hematopoietic mobilization can be used to answer questions regarding hematopoietic stem cell heterogeneity, can be used for non-toxic conditioning of patients receiving stem cell transplants, and can enhance gene editing and gene therapy strategies to cure genetic diseases.

Beta Thalassemia: New Therapeutic Options Beyond Transfusion and Iron Chelation

Hemoglobinopathies are among the most common monogenic diseases worldwide. Approximately 1–5% of the global population are carriers for a genetic thalassemia mutation. The thalassemias are characterized by autosomal recessive inherited defects in the production of hemoglobin. They are highly prevalent in the Mediterranean, Middle East, Indian subcontinent, and East and Southeast Asia. Due to recent migrations, however, the thalassemias are now becoming more common in Europe and North America, making this disease a global health concern. Currently available conventional therapies in thalassemia have many challenges and limitations. A better understanding of the pathophysiology of β-thalassemia in addition to key developments in optimizing transfusion programs and iron-chelation therapy has led to an increase in the life span of thalassemia patients and paved the way for new therapeutic strategies. These can be classified into three categories based on their efforts to address different features of the underlying pathophysiology of β-thalassemia: correction of the globin chain imbalance, addressing ineffective erythropoiesis, and improving iron overload. In this review, we provide an overview of the novel therapeutic approaches that are currently in development for β-thalassemia.

Granulocyte colony-stimulating factor in traumatic spinal cord injury

Granulocyte colony-stimulating factor (G-CSF) is a cytokine used in pharmaceutical preparations for the treatment of chemotherapy-induced neutropenia. Evidence from experimental studies indicates that G-CSF exerts relevant activities in the central nervous system (CNS) in particular after lesions. In acute, subacute, and chronic CNS lesions, G-CSF appears to have strong anti-inflammatory, antiapoptotic, antioxidative, myelin-protective, and axon-regenerative activities. Additional effects result in the stimulation of angiogenesis and neurogenesis as well as in bone marrow stem cell mobilization to the CNS. There are emerging preclinical and clinical data indicating that G-CSF is a safe and effective drug for the treatment of acute and chronic traumatic spinal cord injury (tSCI), which we summarize in this review.

G-CSF shifts erythropoiesis from bone marrow into spleen in the setting of systemic inflammation

The anemia of inflammation is related in part to abnormal erythropoiesis in bone marrow. G-CSF regulates granulopoiesis and is increased during systemic inflammation. Here, we have showed that high levels of G-CSF are associated with repression of bone marrow erythropoiesis and expansion of splenic erythropoiesis in Escherichia coli-infected mice and lipopolysaccharide-treated mice. Under lipopolysaccharide-induced systemic inflammatory conditions in mice, G-CSF neutralization with antibody alleviated the blockage of bone marrow erythropoiesis, prevented the enhancement of splenic erythropoiesis, ameliorated splenomegaly, and reduced the brittleness of spleen. We further demonstrated that after lipopolysaccharide treatment, TLR4-knockout mice display low levels of G-CSF, healthy bone marrow erythropoiesis, almost no stress erythropoiesis in the spleen, and normal size and toughness of spleen. In addition, we found HIF-mediated erythropoietin production is essential for splenic erythropoiesis in the setting of G-CSF-induced suppression of bone marrow erythropoiesis. Our findings identify G-CSF as a critical mediator of inflammation-associated erythropoiesis dysfunction in bone marrow and offer insight into the mechanism of G-CSF-induced splenic erythropoiesis. We provide experimentally significant dimension to the biology of G-CSF.

Curing Hemoglobinopathies: Challenges and Advances of Conventional and New Gene Therapy Approaches

Inherited hemoglobin disorders, including beta-thalassemia (BT) and sickle-cell disease (SCD), are the most common monogenic diseases worldwide, with a global carrier frequency of over 5%.1 With migration, they are becoming more common worldwide, making their management and care an increasing concern for health care systems.

BT is characterized by an imbalance in the α/β-globin chain ratio, ineffective erythropoiesis, chronic hemolytic anemia, and compensatory hemopoietic expansion.1 Globally, there are over 25,000 births each year with transfusion-dependent thalassemia (TDT). The currently available treatment for TDT is lifelong transfusions and iron chelation therapy or allogenic bone marrow transplantation as a curative option. SCD affects 300 million people worldwide2 and severely impacts the quality of life of patients who experience unpredictable, recurrent acute and chronic severe pain, stroke, infections, pulmonary disease, kidney disease, retinopathy, and other complications. While survival has been dramatically extended, quality of life is markedly reduced by disease- and treatment-associated morbidity.

The development of safe, tissue-specific and efficient vectors, and efficient gene-editing technologies have led to the development of several gene therapy trials for BT and SCD. However, the complexity of the approach presents its hurdles. Fundamental factors at play include the requirement for myeloablation on a patient with benign disease, the age of the patient, and the consequent bone marrow microenvironment. A successful path from proof-ofconcept studies to commercialization must render gene therapy a sustainable and accessible approach for a large number of patients. Furthermore, the cost of these therapies is a considerable challenge for the health care system. While new promising therapeutic options are emerging,3,4 and many others are on the pipeline,5 gene therapy can potentially cure patients. We herein provide an overview of the most recent, likely potentially curative therapies for hemoglobinopathies and a summary of the challenges that these approaches entail.

Gene Therapy For Beta-Thalassemia: Updated Perspectives

Allogeneic hematopoietic stem cell transplantation was until very recently, the only permanent curative option available for patients suffering from transfusion-dependent beta-thalassemia. Gene therapy, by autologous transplantation of genetically modified hematopoietic stem cells, currently represents a novel therapeutic promise, after many years of extensive preclinical research for the optimization of gene transfer protocols. Nowadays, clinical trials being held on a worldwide setting, have demonstrated that, by re-establishing effective hemoglobin production, patients may be rendered transfusion- and chelation-independent and evade the immunological complications that normally accompany allogeneic hematopoietic stem cell transplantation. The present review will offer a retrospective scope of the long way paved towards successful implementation of gene therapy for beta-thalassemia, and will pinpoint the latest strategies employed to increase globin expression that extend beyond the classic transgene addition perspective. A thorough search was performed using Pubmed in order to identify studies that provide a proof of principle on the aforementioned topic at a preclinical and clinical level. Inclusion criteria also regarded gene transfer technologies of the past two decades, as well as publications outlining the pitfalls that precluded earlier successful implementation of gene therapy for beta-thalassemia. Overall, after decades of research, that included both successes and pitfalls, the path towards a permanent, donor-irrespective cure for beta-thalassemia patients is steadily becoming a realistic approach.

On the origin of myeloid-derived suppressor cells

Myeloid-derived suppressor cells (MDSCs) have a strong immunosuppressive character that allows them to regulate immune responses and hinder overt inflammatory responses. In cancer, this leads to tumor immune evasion and disease progression. MDSCs come in at least two forms: monocytic (Mo-MDSCs) and granulocytic (G-MDSCs). The classical definition of MDSCs as immature myeloid cells blocked from differentiating has been challenged by recent studies suggesting that Mo-MDSCs and G-MDSCs may represent monocytes and granulocytes that have acquired immunosuppressive properties. The molecular mechanism behind their generation and their true origins are now widely debated. In this review we discuss the different proposed mechanisms of the generation of both types of MDSCs, with a special focus on human MDSCs in cancer.

Ultrasound-guided percutaneous portal transplantation of peripheral blood monocytes in patients with liver cirrhosis

BACKGROUND/AIMS

Liver transplantation offers the only definite cure for cirrhosis but lacking donors is problem. Stem cell therapy is attractive in this setting. In this study, we aimed to explore the safety and efficacy of ultrasound-guided percutaneous portal transplantation of peripheral blood monocyte cell (PBMC) in cirrhotic patients.

METHODS

A total of nine decompensated cirrhotic patients were randomized into three groups: group 1 (n = 3) was control group, group 2 (n = 3) received granulocyte-colony stimulating factor (G-CSF) mobilization for 3 days, and group 3 (n = 3) received G-CSF mobilized PBMCs by leukapheresis and PBMC transplantation through ultrasound-guided percutaneous portal vein puncture. Liver function and clinical features were evaluated.

RESULTS

At baseline, the Child-Turcotte-Pugh and the model for end-stage liver disease scores were comparable in study groups. Compared with group 1, there was a tendency to improve liver function in group 3 at 6 months after treatment. Treatment was tolerable and no complications were encountered related to the G-CSF mobilization or percutaneous portal administration of PBMCs. Imaging studies showed patent portal veins at the end of the study period.

CONCLUSIONS

Autologous PBMC transplantation through ultrasound-guided percutaneous portal vein puncture could be considered as a safe alternative treatment for decompensated cirrhotic patients.

Spontaneous splenic rupture following stem cell mobilization with G-CSF and plerixafor in AL amyloidosis

BACKGROUND

AL amyloidosis is a rare plasma cell dyscrasia with multiorgan involvement. Good risk patients are candidate to high dose chemotherapy and autologous stem cell transplantation. However both transplantation and stem cell collection entail significant risk in such patients. Plerixafor is a novel mobilizing agent approved for use in "poor mobilizer" patients with lymphoma and multiple myeloma; experience in systemic amyloidosis patients is limited.

CASE REPORT

We describe a case of spontaneous splenic rupture following administration of G-CSF and plerixafor in a patient with AL amyloidosis who previously underwent heart transplantation due to amyloid heart involvement.

RESULTS AND CONCLUSION

This is the first report of spontaneous splenic rupture following stem cell mobilization with G-CSF and plerixafor in AL amyloidosis. The role of plerixafor has to be established. AL amyloidosis patients undergoing stem cell mobilization need careful monitoring of signs and symptoms of spontaneous splenic rupture.

Plerixafor on demand in ten healthy family donors as a rescue strategy to achieve an adequate graft for stem cell transplantation

BACKGROUND

In allogeneic hematopoietic stem cell (HSC) transplantation, the collection of an appropriate number of HSCs while maintaining a high level of safety for healthy donors is fundamental. Inadequate HSC mobilization can be seen with the standard use of granulocyte-colony-stimulating (G-CSF). Plerixafor (PL) is a chemokine receptor CXC Type 4-stromal-derived factor 1 inhibitor; its HSC-mobilizing properties are synergistic with G-CSF in poor mobilizing patients. The use of PL as adjuvant or alternative to G-CSF in healthy donors has shown a good safety profile but is so far off-label.

STUDY DESIGN AND METHODS

We report 10 healthy HSC donors treated with PL because of insufficient response to G-CSF alone or contraindication to G-CSF. Eight donors did not mobilize enough CD34+ cells with G-CSF alone because poor mobilizers or because insufficient HSCs were harvested according to the clinical need of the patient; in two cases G-CSF administration and marrow harvest were unfeasible or contraindicated in the donor.

RESULTS

The use of PL for mobilization increased the number of circulating CD34+ cells by 2.8-fold and the CD34+/kg collection by 3.0-fold. Only mild adverse events were reported (bone pain or discomfort) and not univocally attributable to PL. Rate of engraftment and graft-versus-host disease were similar to those seen in recipients of grafts from G-CSF only-mobilized donors.

CONCLUSION

We exposed 10 allogeneic donors to mobilization with PL. PL was well tolerated in all cases and ensured procurement of an adequate graft for transplantation resulting in a normal hematopoietic engraftment.

Concise review: Sowing the seeds of a fruitful harvest: hematopoietic stem cell mobilization

Hematopoietic stem cell transplantation is the only curative option for a number of malignant and nonmalignant diseases. As the use of hematopoietic transplant has expanded, so too has the source of stem and progenitor cells. The predominate source of stem and progenitors today, particularly in settings of autologous transplantation, is mobilized peripheral blood. This review will highlight the historical advances which led to the widespread use of peripheral blood stem cells for transplantation, with a look toward future enhancements to mobilization strategies.

Current Status and Developments in Gene Therapy for Thalassemia and Sickle Cell Disease

β-thalassemias and sickle cell anemia (SCA) are the most common monogenic diseases worldwide for which curative treatments remain a desired goal. Allogeneic hematopoietic stem cell transplantation (allo-HCT), - the only curative treatment currently available for hemoglobinopaties-, has a narrow application window whereas it incurs several immunological risks. Gene therapy (GT), that is the autologous transplantation of genetically modified hematopoietic stem cells (CD34+), represents a promising new therapeutic strategy which is anticipated to reestablish effective hemoglobin production and render patients transfusion- and drug- independent without the immunological complications that normally accompany allo-HCT. Prior to the application of GT for hemoglobinopathies in the clinic, many years of extensive preclinical research were spent for the optimization of the gene transfer tools and conditions. To date, three GT clinical trials for β-thalassemia and sickle cell disease (SCD) have been conducted or are in progress and 3 cases of transfusion independence in thalassemic β0/βΕ patients have been reported. In the present review, the prerequisites for successful implementation of GT, the tough pathway of GT for hemoglobinopathies towards the clinic and the knowledge gained from the first clinical trials as well as the remaining questions and challenges, will be discussed. Overall, after decades of research including achievements but pitfalls as well, the path to GT of human patients with hemoglobinopathies is currently open and highly promising...

A hyperactive Mpl-based cell growth switch drives macrophage-associated erythropoiesis through an erythroid-megakaryocytic precursor

Several approaches for controlling hematopoietic stem and progenitor cell expansion, lineage commitment, and maturation have been investigated for improving clinical interventions. We report here that amino acid substitutions in a thrombopoietin receptor (Mpl)--containing cell growth switch (CGS) extending receptor stability improve the expansion capacity of human cord blood CD34(+) cells in the absence of exogenous cytokines. Activation of this CGS with a chemical inducer of dimerization (CID) expands total cells 99-fold, erythrocytes 70-fold, megakaryocytes 0.5-fold, and CD34(+) stem/progenitor cells 4.4-fold by 21 days of culture. Analysis of cells in these expanded populations identified a CID-dependent bipotent erythrocyte-megakaryocyte precursor (PEM) population, and a CID-independent macrophage population. The CD235a(+)/CD41a(+) PEM population constitutes up to 13% of the expansion cultures, can differentiate into erythrocytes or megakaryocytes, exhibits very little expansion capacity, and exists at very low levels in unexpanded cord blood. The CD206(+) macrophage population constitutes up to 15% of the expansion cultures, exhibits high-expansion capacity, and is physically associated with differentiating erythroblasts. Taken together, these studies describe a fundamental enhancement of the CGS expansion platform, identify a novel precursor population in the erythroid/megakaryocytic differentiation pathway of humans, and implicate an erythropoietin-independent, macrophage-associated pathway supporting terminal erythropoiesis in this expansion system.

Peripheral blood progenitor cell mobilization for autologous and allogeneic hematopoietic cell transplantation: guidelines from the American Society for Blood and Marrow Transplantation

Peripheral blood progenitor cell mobilization practices vary significantly among institutions. Effective mobilization regimens include growth factor alone, chemotherapy and growth factor combined, and, more recently, incorporation of plerixafor with either approach. Many institutions have developed algorithms to improve stem cell mobilization success rates and cost-effectiveness. However, an optimal stem cell mobilization regimen has not been defined. Practical guidelines are needed to address important clinical questions, including which growth factor is optimal, what chemotherapy and dose is most effective, and when to initiate leukapheresis. We present recommendations, based on a comprehensive review of the literature, from the American Society of Blood and Marrow Transplantation.

Bone marrow derived stem cells for the treatment of end-stage liver disease

End-stage disease due to liver cirrhosis is an important cause of death worldwide. Cirrhosis results from progressive, extensive fibrosis and impaired hepatocyte regeneration. The only curative treatment is liver transplantation, but due to the several limitations of this procedure, the interest in alternative therapeutic strategies is increasing. In particular, the potential of bone marrow stem cell (BMSC) therapy in cirrhosis has been explored in different trials. In this article, we evaluate the results of 18 prospective clinical trials, and we provide a descriptive overview of recent advances in the research on hepatic regenerative medicine. The main message from the currently available data in the literature is that BMSC therapy is extremely promising in the context of liver cirrhosis. However, its application should be further explored in randomized, controlled trials with large cohorts and long follow-ups.

Hematopoietic stem cell mobilization for gene therapy: superior mobilization by the combination of granulocyte-colony stimulating factor plus plerixafor in patients with β-thalassemia major

Successful stem cell gene therapy requires high numbers of genetically engineered hematopoietic stem cells collected using optimal mobilization strategies. Here we focus on stem cell mobilization strategies for thalassemia and present the results of a plerixafor-based mobilization trial with emphasis on the remobilization with granulocyte-colony stimulating factor (G-CSF)+plerixafor in those patients who had previously failed mobilization. Plerixafor rapidly mobilized CD34(+) cells without inducing hyperleukocytosis; however, 35% of patients failed to reach the target cell dose of ≥6×10(6) CD34(+) cells/kg. Four subjects who failed on either plerixafor or G-CSF were remobilized with G-CSF+plerixafor. The combination proved highly synergistic; the target cell dose was readily reached and the per-apheresis yield was significantly increased over initial mobilization, ultimately resulting in single-apheresis collections, despite a more than 50% reduction of the dose of G-CSF in splenectomized patients to avoid hyperleukocytosis. The total stem and progenitor cells mobilized in G-CSF+plerixafor patients were higher than in patients treated by plerixafor alone. Importantly, the G-CSF+plerixafor-mobilized cells displayed a primitive stem cell phenotype and higher clonogenic capacity over plerixafor-mobilized cells. G-CSF+plerixafor represents the optimal strategy when very high yields of stem cells or a single apheresis is required. The high yields and the favorable transplantation features render the G-CSF+plerixafor-mobilized cells the optimal CD34(+) cell source for stem cell gene therapy applications.

Harvesting autologous stem cells from a patient with red blood cell abnormalities of β-thalassemia intermedia

BACKGROUND

Autologous stem cell transplants in patients with hemoglobinopathies are limited. Previous reports used granulocyte-colony-stimulating factor (G-CSF) for mobilization of stem cells; there are no reported cases undergoing plerixafor mobilization. We report such a patient, providing guidance for peripheral blood stem cells collection when aberrant red blood cells (RBCs) disrupt normal separation.

STUDY DESIGN AND METHODS

A patient with β-thalassemia intermedia and hereditary persistence of fetal hemoglobin presented for peripheral blood stem cell collection for autologous transplant for myeloma. He underwent splenectomy for anemia secondary to hemoglobinopathy and chemotherapy, ceasing RBC transfusions. The patient was mobilized using plerixafor after collection with G-CSF failed.

RESULTS

Collections were performed using an apheresis system, processing 24 L daily. Peripheral blood and apheresis product CD34 determinations were performed daily. On Day 1, the product yield was 0.04 × 10(6) CD34 cells/kg, less than expected based on white blood cell count and CD34-positive cells. Peripheral blood smear showed nucleated RBCs and RBC morphologic abnormalities. Changes in instrument variables were made after consultation with Terumo BCT to adjust for variable distribution of mononuclear and stem cells during centrifugation. Collecting stem cells at a deeper location and centrifuging faster improved collection, and a cumulative total of 4.40 × 10(6) CD34 cells/kg was achieved after four collections. The patient underwent tandem autologous transplantation and engrafted within 12 to 13 days of each transplant.

CONCLUSIONS

Adjustments in apheresis variables allowed successful collection of peripheral blood stem cells from a patient with RBC anomalies of β-thalassemia that interfered with standard stem cell harvesting.

A rare but severe complication of filgrastim in a healthy donor: splenic rupture

BACKGROUND

Granulocyte-colony stimulating factor (G-CSF) is widely administered to donors who provide peripheral blood stem cells (PBSCs) for individuals who undergo hematopoietic stem cell transplants. G-CSF administration is associated with a small but definite risks of serious adverse events like splenic rupture.

CASE STUDY

In this case, we report a 40 year old women, a healthy donor for her sister who has aplastic anemia, who had sharp left upper abdominal pain on the forth mobilization day. The diagnosis at CT scan was splenic rupture; irregular intrasplenic low-attenuation areas consistent with ruptured spleen and perisplenic high density fluid. Her bidimensional spleen size was 16×6 cm.

RESULTS

She was followed conservatively. One month later the CT scan signs of rupture disappeared.

CONCLUSION

We must pay attention to this rare but serious adverse event during filgrastim use.

PBSC collection from family donors in Japan: a prospective survey

Severe adverse events (SAE) and late hematological malignancies have been reported after PBSC donation. No prospective data on incidence and risk factors have been available for family donors so far. The Japan Society for Hematopoietic Cell Transplantation (JSHCT) introduced therefore in 2000 a mandatory registration system. It defined standards for donor eligibility and asked harvest centers to report any SAE immediately. All donors were examined at day 30 and were to be contacted once each year for a period of 5 years. Acute SAEs within day 30 were reported from 47/3264 donations (1.44%) with 14 events considered as unexpected and severe (0.58%). No donor died within 30 days. Late SAEs were reported from 39/1708 donors (2.3%). The incidence of acute SAEs was significantly higher among donors not matching the JSHCT standards (P=0.0023). Late hematological malignancies in PBSC donors were not different compared with a retrospective cohort of BM donors (N:1/1708 vs N:2/5921; P=0.53). In conclusion, acute and late SAEs do occur in PBSC donors at relatively low frequency but risk factors can be defined.

G-CSF in Healthy Allogeneic Stem Cell Donors

Mobilization of peripheral blood stem cells (PBSC) in healthy volunteers with granulocyte colony-stimulating factor (G-CSF) is currently carried out at many institutions worldwide. This report presents the experience of the Dresden center regarding donor evaluation and mobilization schedule. Data regarding efficacy, short- and long-term safety of G-CSF treatment gained from 8290 PBSC collections in healthy donors are outlined. These results are discussed against the background of the available evidence from the literature. Although established as a standard procedure, G-CSF application to allogeneic donors will always be a very delicate procedure and requires the utmost commitment of all staff involved to ensure maximum donor safety.

Wiskott-Aldrich syndrome protein-deficient hematopoietic cells can be efficiently mobilized by granulocyte colony-stimulating factor

The Wiskott-Aldrich syndrome protein is an essential cytoskeleton regulator found in cells of the hematopoietic lineage and controls the motility of leukocytes. The impact of WAS gene deficiency on the mobilization of hematopoietic progenitor/stem cells in circulation has remained unexplored but information would be pertinent in the context of autologous gene therapy of Wiskott-Aldrich syndrome. The response to granulocyte-colony stimulating factor mobilization was investigated in a murine WAS knock-out model of the disease, by measuring hematologic parameters, circulation and engraftment of hematopoietic progenitor/stem cells. In the steady-state, adult WAS knock-out mice have B-cell lymphopenia, marked neutrophilia, increased counts of circulating hematopoietic progenitor cells and splenomegaly, presumably caused by the retention of hematopoietic progenitor cells due to high levels of splenic CXCL12. In spite of these anomalies, the administration of granulocyte-colony-stimulating factor mobilizes progenitor/stem cells in WAS knock-out mice to the same level and with the same kinetics as in wild-type control mice. Mobilized peripheral blood cells from WAS knock-out mice can be transduced and are able to engraft into lethally-irradiated hosts reconstituting multiple lineages of cells and providing more effective radio-protection than mobilized cells from wild-type control mice. Surprisingly, the homing and the peripheral blood recovery of B lymphocytes was influenced by the background of the host. Thus, in the absence of Wiskott-Aldrich syndrome protein, effective mobilization is achieved but partial correction may occur as a result of an abnormal hematopoietic environment.

Advances in stem cell mobilization

The use of mobilized peripheral blood stem cells (PBSCs) has largely replaced the use of bone marrow as a source of stem cells for both allogeneic and autologous stem cell transplantation. G-CSF with or without chemotherapy is the most commonly used regimen for stem cell mobilization. Some donors or patients, especially the heavily pretreated patients, fail to mobilize the targeted number of stem cells with this regimen. A better understanding of the mechanisms involved in hematopoietic stem cell (HSC) trafficking could lead to the development of newer mobilizing agents and therapeutic approaches. This review will cover the current methods for stem cell mobilization and recent developments in the understanding of the biology of stem cells and the bone marrow microenvironment.

Phase I study of intravenous low-dose granulocyte colony-stimulating factor in acute and subacute ischemic stroke

BACKGROUND

Granulocyte colony-stimulating factor (G-CSF; filgrastim) may be useful for the treatment of acute ischemic stroke because of its neuroprotective and neurogenesis-promoting properties, but an excessive increase of neutrophils may lead to brain injury. We examined the safety and tolerability of low-dose G-CSF and investigated the effectiveness of G-CSF given intravenously in the acute phase (at 24 hours) or subacute phase (at 7 days) of ischemic stroke.

METHODS

Three intravenous dose regimens (150, 300, or 450 μg/body/day, divided into 2 doses for 5 days) of G-CSF were examined in 18 patients with magnetic resonance imaging (MRI)-confirmed infarct in the territory of the middle cerebral artery. Nine patients received the first dose at 24 hours poststroke (acute group) and 9 patients received the first dose on day 7 poststroke (subacute group; n = 3 at each dose in each group). A scheduled administration of G-CSF was skipped if the patient's leukocyte count exceeded 40,000/μL. Patients received neurologic and MRI examinations.

RESULTS

We found neither serious adverse event, drug-related platelet reduction nor splenomegaly. Leukocyte levels remained below 40,000/μL at 150 and 300 μg G-CSF/body/day, but rose above 40,000/μL at 450 μg G-CSF/body/day. Neurologic function improvement between baseline and day 90 was more marked after treatment in the acute phase versus the subacute phase (Barthel index 49.4 ± 28.1 v 15.0 ± 22.0; P < .01).

CONCLUSIONS

Low-dose G-CSF (150 and 300 μg/body/day) was safe and well tolerated in ischemic stroke patients, and leukocyte levels remained below 40,000/μL.

613 cases of splenic rupture without risk factors or previously diagnosed disease: a systematic review

BACKGROUND

Rupture of the spleen in the absence of trauma or previously diagnosed disease is largely ignored in the emergency literature and is often not documented as such in journals from other fields. We have conducted a systematic review of the literature to highlight the surprisingly frequent occurrence of this phenomenon and to document the diversity of diseases that can present in this fashion.

METHODS

Systematic review of English and French language publications catalogued in Pubmed, Embase and CINAHL between 1950 and 2011.

RESULTS

We found 613 cases of splenic rupture meeting the criteria above, 327 of which occurred as the presenting complaint of an underlying disease and 112 of which occurred following a medical procedure. Rupture appeared to occur spontaneously in histologically normal (but not necessarily normal size) spleens in 35 cases and after minor trauma in 23 cases. Medications were implicated in 47 cases, a splenic or adjacent anatomical abnormality in 31 cases and pregnancy or its complications in 38 cases. The most common associated diseases were infectious (n = 143), haematologic (n = 84) and non-haematologic neoplasms (n = 48). Amyloidosis (n = 24), internal trauma such as cough or vomiting (n = 17) and rheumatologic diseases (n = 10) are less frequently reported. Colonoscopy (n = 87) was the procedure reported most frequently as a cause of rupture. The anatomic abnormalities associated with rupture include splenic cysts (n = 6), infarction (n = 6) and hamartomata (n = 5). Medications associated with rupture include anticoagulants (n = 21), thrombolytics (n = 13) and recombinant G-CSF (n = 10). Other causes or associations reported very infrequently include other endoscopy, pulmonary, cardiac or abdominal surgery, hysterectomy, peliosis, empyema, remote pancreato-renal transplant, thrombosed splenic vein, hemangiomata, pancreatic pseudocysts, splenic artery aneurysm, cholesterol embolism, splenic granuloma, congenital diaphragmatic hernia, rib exostosis, pancreatitis, Gaucher's disease, Wilson's disease, pheochromocytoma, afibrinogenemia and ruptured ectopic pregnancy.

CONCLUSIONS

Emergency physicians should be attuned to the fact that rupture of the spleen can occur in the absence of major trauma or previously diagnosed splenic disease. The occurrence of such a rupture is likely to be the manifesting complaint of an underlying disease. Furthermore, colonoscopy should be more widely documented as a cause of splenic rupture.

A feasible shortcut for the mobilization outcome: Steady state CD34 positive hematopoietic stem cells

Predicting success of hematopoietic cell mobilization is an important issue for transplant physicians. We examined the steady state peripheral blood CD34+ cell count to predict ability to mobilize adequate hematopoietic progenitor cells in 63 myeloma and lymphoma patients. The median steady state CD34+ cell number was 1.56/μL (0.03-5.76). Although counting steady state CD34+ is definitely cost effective to predict the successful mobilization, we could not find a threshold steady state CD34 count of any value predicting successful mobilization.

Stem cell therapy in chronic liver disease

PURPOSE OF REVIEW

To provide an overview of the current status of liver regeneration therapies for liver cirrhosis and future prospects.

RECENT FINDINGS

Various clinical studies for liver disease have been reported, including hepatic administration of autologous CD34-positive cells induced by granulocyte colony-stimulating factor, portal vein administration of CD133-positive mononuclear cells, and administration of autologous bone marrow-derived mesenchymal stem cells. Effectiveness of these approaches has been shown in some patients. We have also reported improved liver fibrosis and function with infusion of autologous bone marrow cells in a basic study with mice, and on the basis of those results started autologous bone marrow cell infusion (ABMi) therapy for liver cirrhosis. The efficacy and safety of ABMi therapy has also been reported by other institutions.

SUMMARY

Results of recent clinical studies strongly suggest that liver function-improving effects can be achieved using infusion of bone marrow (stem) cells for cirrhosis. New treatment methods using less-invasive bone marrow-derived cultured cells need to be developed.

Timeline for development of autologous bone marrow infusion (ABMi) therapy and perspective for future stem cell therapy

Liver cirrhosis patients generally progress to liver failure. To cure this progressive disease, we developed a novel cell therapy using bone marrow cells; autologous bone marrow cell infusion (ABMi) therapy. We previously described the possible action mechanism of ABMi therapy in the cirrhotic liver, and showed the timeline and results of clinical studies of ABMi therapy. We have also carried out other clinical studies using bone marrow cells and granulocyte colony-stimulating factor. Here, we report a new randomized clinical trial to evaluate the effects of ABMi therapy. However, ABMi therapy may not be possible in patients who are unable to undergo general anesthesia; therefore, we have started to develop a next-generation stem cell therapy using cultured mesenchymal stem cells.

Neuroprotective therapy using granulocyte colony-stimulating factor for acute spinal cord injury: a phase I/IIa clinical trial

OBJECTIVE

Granulocyte colony-stimulating factor (G-CSF) is a cytokine that is clinically used to treat neutropenia. G-CSF also has non-hematopoietic functions and could potentially be used to treat neuronal injury. To confirm the safety and feasibility of G-CSF administration for acute spinal cord injury (SCI), we have initiated a phase I/IIa clinical trial of neuroprotective therapy using G-CSF.

METHODS

The trial included a total of 16 SCI patients within 48 h of onset. In the first step, G-CSF (5 μg/kg/day) was intravenously administered for 5 consecutive days to 5 patients. In the second step, G-CSF (10 μg/kg/day) was similarly administered to 11 patients. We evaluated motor and sensory functions of patients using the American Spinal Cord Injury Association (ASIA) score and ASIA impairment scale (AIS) grade.

RESULTS

In all 16 patients, neurological improvement was obtained after G-CSF administration. AIS grade increased by one step in 9 of 16 patients. A significant increase in ASIA motor scores was detected 1 day after injection (P < 0.01), and both light touch and pin prick scores improved 2 days after injection (P < 0.05) in the 10 μg group. No severe adverse effects were observed after G-CSF injection.

CONCLUSION

These results indicate that intravenous administration of G-CSF (10 μg/kg/day) for 5 days is essentially safe, and suggest that some neurological recovery may occur in most patients. We suggest that G-CSF administration could be therapeutic for patients with acute SCI.

Mobilization of hematopoietic stem and progenitor cells using inhibitors of CXCR4 and VLA-4

Successful hematopoietic stem cell transplant requires the infusion of a sufficient number of hematopoietic stem/progenitor cells (HSPCs) that are capable of homing to the bone marrow cavity and regenerating durable trilineage hematopoiesis in a timely manner. Stem cells harvested from peripheral blood are the most commonly used graft source in HSCT. Although granulocyte colony-stimulating factor (G-CSF) is the most frequently used agent for stem cell mobilization, the use of G-CSF alone results in suboptimal stem cell yields in a significant proportion of patients. Both the chemokine receptor CXCR4 and the integrin α(4)β(1) (very late antigen 4 (VLA-4)) have important roles in the homing and retention of HSPCs within the bone marrow microenvironment. Preclinical and/or clinical studies have shown that targeted disruption of the interaction of CXCR4 or VLA-4 with their ligands results in the rapid and reversible mobilization of hematopoietic stem cells into the peripheral circulation and is synergistic when combined with G-CSF. In this review, we discuss the development of small-molecule CXCR4 and VLA-4 inhibitors and how they may improve the utility and convenience of peripheral blood stem cell transplantation.

Hematopoietic stem cell mobilization for gene therapy of adult patients with severe β-thalassemia: results of clinical trials using G-CSF or plerixafor in splenectomized and nonsplenectomized subjects

The safety and efficacy of hematopoietic stem cell (HSC) mobilization was investigated in adult splenectomized (SPL) and non-SPL patients with thalassemia major, in two clinical trials, using different mobilization modes: granulocyte-colony-stimulating factor (G-CSF)-alone, G-CSF following pretreatment with hydroxyurea (HU), plerixafor-alone. G-CSF-mobilization was both safe and effective in non-SPL patients. However, in SPL patients the procedure resulted in excessive response to G-CSF, expressed as early hyperleukocytosis necessitating significant dose reduction, and suboptimal CD34(+) cells yields. One-month HU-pretreatment prevented hyperleukocytosis and allowed successful CD34(+) cell collections when an optimal washout period was maintained, but it significantly prolonged the mobilization procedure. Plerixafor resulted in rapid and effective mobilization in both SPL and non-SPL patients and was well-tolerated. For gene therapy of thalassemia, G-CSF or Plerixafor could be used as mobilization agents in non-SPL patients whereas Plerixafor appears to be the mobilization agent of choice in SPL adult thalassemics in terms of safety and efficacy.

Bone marrow as a source of hematopoietic stem cells for human gene therapy of β-thalassemia

β-Thalassemia is a severe inherited anemia caused by insufficient production of β-globin chains. Allogeneic hematopoietic stem cell (HSC) transplantation is currently the only cure, and is limited by donor availability and regimen-related toxicity and mortality. Gene therapy is a promising therapeutic tool for all thalassemic patients lacking a compatible donor and potentially provides transfusion independence in the absence of transplant-related complications, such as graft rejection and graft-versus-host disease. The issue of HSC procurement is critical in this setting because of the specific features of thalassemic syndromes, which include bone marrow (BM) expansion, ineffective erythropoiesis, and splenomegaly. Little is known about the efficiency of CD34(+) cell yield from steady-state BM harvests from thalassemic patients. We have collected data on safety and cell yield from 20 pediatric patients with β-thalassemia who underwent autologous BM harvest before allogeneic HSC transplantation, and from 49 age-matched sibling donors who also underwent BM harvest. The procedure was safe, as no significant adverse events occurred. In terms of cell yield, no difference was found between patients and normal donors in the number of CD34(+) cells and total nucleated cells harvested. Most importantly, no difference was found in the proportion of myeloid and erythroid progenitors, suggesting a similar repopulating capacity. On the basis of these results, we conclude that steady-state BM can be used as a safe and efficient source of HSC for gene therapy of β-thalassemia.

Lentiviral gene transfer regenerates hematopoietic stem cells in a mouse model for Mpl-deficient aplastic anemia

Thpo/Mpl signaling plays an important role in the maintenance of hematopoietic stem cells (HSCs) in addition to its role in megakaryopoiesis. Patients with inactivating mutations in Mpl develop thrombocytopenia and aplastic anemia because of progressive loss of HSCs. Yet, it is unknown whether this loss of HSCs is an irreversible process. In this study, we used the Mpl knockout (Mpl(-/-)) mouse model and expressed Mpl from newly developed lentiviral vectors specifically in the physiologic Mpl target populations, namely, HSCs and megakaryocytes. After validating lineage-specific expression in vivo using lentiviral eGFP reporter vectors, we performed bone marrow transplantation of transduced Mpl(-/-) bone marrow cells into Mpl(-/-) mice. We show that restoration of Mpl expression from transcriptionally targeted vectors prevents lethal adverse reactions of ectopic Mpl expression, replenishes the HSC pool, restores stem cell properties, and corrects platelet production. In some mice, megakaryocyte counts were atypically high, accompanied by bone neo-formation and marrow fibrosis. Gene-corrected Mpl(-/-) cells had increased long-term repopulating potential, with a marked increase in lineage(-)Sca1(+)cKit(+) cells and early progenitor populations in reconstituted mice. Transcriptome analysis of lineage(-)Sca1(+)cKit(+) cells in Mpl-corrected mice showed functional adjustment of genes involved in HSC self-renewal.

Transient neutropenia after granulocyte-colony stimulating factor administration is associated with neutrophil accumulation in pulmonary vasculature

OBJECTIVE

To better define the nature of the transient neutropenia shortly following granulocyte-colony stimulating factor (G-CSF) administration.

MATERIALS AND METHODS

To evaluate the disappearance of neutrophils, we investigated neutrophil trafficking. Ratios of neutrophil number to background cellularity for C57BL/6 LysM-EGFP knock-in mice and rhesus macaques were determined in the lung, liver, spleen, and kidney after G-CSF administration.

RESULTS

For the C57BL/6 LysM-EGFP knock-in mice, the enhanced green fluorescent protein expression (EGFP(+)) cells increased in the lung and spleen within 15 minutes of administering 50 μg/kg G-CSF subcutaneously, and continued to increase in the lung and spleen from 15 minutes to 30 minutes. At 240 minutes, the pulmonary infiltrate declined to a level comparable to the level at 15 minutes, while in the spleen EGFP(+) cells continued to increase. For rhesus macaques, CD18(+) cells also significantly increased in the lung 30 minutes after administration of 10 μg/kg G-CSF subcutaneously compared to the control level.

CONCLUSIONS

These results suggest that the transient neutropenia following G-CSF administration in the mouse and nonhuman primate is associated with an accumulation of neutrophils within pulmonary and splenic vasculature.

Hematopoietic stem cell mobilization strategies for gene therapy of beta thalassemia and sickle cell disease

Effective gene therapy for hemoglobinopathies will require high numbers of autologous gene-engineered hematopoetic stem cells to be reintroduced into the patients. Stem cell mobilization using G-CSF is the most convenient and effective approach to achieve this goal, but it can have severe side effects in sickle cell anemia and be potentially harmful in the case of severe thalassemia. Hence, the optimal way of collection of hematopoetic stem cells from patients with thalassemia and sickle cell disease needs to be determined. In this paper, we review the possible risks of G-CSF mobilization in hemoglobinopathies and we outline the approaches used in an on-going clinical trial in which pretreatment with hydroxyurea is used to reduce potential risks of G-CSF administration to patients with severe beta thalassemia.

Mobilization of hematopoietic stem cells in a thalassemic mouse model: implications for human gene therapy of thalassemia

Granulocyte colony-stimulating factor (G-CSF)-mobilized blood stem cells may become the preferable source of hematopoietic stem cells (HSCs) for gene therapy because of the higher yield of cells compared with conventional bone marrow harvesting. A G-CSF-associated risk of splenic rupture has been recognized in normal donors of HSCs, but limited information is available about the G-CSF effect in the presence of splenomegaly and extramedullary hematopoiesis. We investigated the G-CSF effect in a thalassemic mouse model (HBB(th-3)) as compared with a normal strain (C57BL/6), in terms of safety, mobilization efficacy, and distribution of stem cells among hematopoietic compartments. There was no death or clinical sequelae of splenic rupture in G-CSF-treated animals of either strain; however, hemorrhagic infarcts in the spleen were detected with low frequency in G-CSF-treated HBB(th-3) mice (12.5%). HBB(th-3) mice mobilized less effectively than C57BL/6 mice (Lin(-)Sca-1(+)c-Kit(+) cells/microl of peripheral blood mononuclear cells [PBMCs]: 90 +/- 55 vs. 255 +/- 174, respectively, p = 0.01; CFU-GM/ml PBMCs: 390 +/- 262 vs. 1131 +/- 875, p = 0.01) because of increased splenic trapping of hematopoietic stem and progenitor cells (Lin(-)Sca-1(+)c-Kit(+) cells per spleen (x10(5)): 487 +/- 35 vs. 109 +/- 19.6, p = 0.01; CFU-GM per spleen (x10(2)): 1470 +/- 347 vs. 530 +/- 425, p = 0.0006). Splenectomy restored the mobilization proficiency of thalassemic mice at comparable levels to normal mice and resulted in the development of a hematopoietic compensatory mechanism in the thalassemic liver that protected splenectomized mice from severe anemia. Our data imply that, in view of human gene therapy for thalassemia, either multiple cycles or alternative ways of mobilization may be required for a sufficient yield of transplantable HSCs. In addition, strategies to minimize the risk of G-CSF-induced splenic infarcts should be explored in a clinical setting.

Heart rate variability during and after peripheral blood stem cell leukapheresis in autologous transplant patients and allogeneic transplant donors

Side effects of varying severity are frequent in peripheral blood stem cell harvest (PBSCH). Life-threatening complications associated with PBSCH have also been reported. Heart rate variability (HRV), which reflects sympathovagal balance and autonomic cardiovascular control, has been a subject of intense interest in various diseases precipitating sudden death. Here, we prospectively assessed the impact of leukapheresis on HRV among autologous hematopoietic cell transplant patients and healthy donors. We found that HRV indicators, the standard deviation of normal-to-normal intervals (SDNN) value, the square root of the mean of the sum of squared differences between the adjacent normal-to-normal interval (r-MSSD) value, total frequency (TF), high frequency (HF) and low frequency (LF) powers decreased significantly to morbid levels during leukapheresis (all P < 0.01). Morbid changes in SDNN value, TF and LF powers were significantly sustained for 6-9 h after leukapheresis (all P < 0.05). Furthermore, TF and LF powers prior to leukapheresis were significantly lower in subjects with symptomatic hypotension than in the other subjects [3282 (3121-4427) vs. 6018 (4983-9816) ms(2), P = 0.03; 93 (42-144) vs. 237 (142-360) ms(2), P = 0.03, respectively]. Our results suggest that HRV analysis might be of use in evaluating and predicting the adverse effects of cardiovascular complications in PBSCH.

Stem cell donation--what advice can be given to the donor?

Haematopoietic stem cell transplantation (HSCT) is widely used to treat patients with a range of haematological and non-haematological disorders. Both bone marrow and peripheral blood stem cell collection are associated with morbidity and, very rarely, mortality. We investigated the information that exists to adequately inform donors about the relative merits of each procedure. We carried out a systematic review analysing data from six prospective randomised controlled trials of related donors and discuss here the merits and drawbacks of this approach. Registry data mostly describes patient outcome but stem cell donor registries collect and report information on unrelated donors which could easily be extended to related donors. Further well-designed, randomised studies are required.

Adverse events among 2408 unrelated donors of peripheral blood stem cells: results of a prospective trial from the National Marrow Donor Program

Limited data are available describing donor adverse events (AEs) associated with filgrastim mobilized peripheral blood stem cell (PBSC) collections in unrelated volunteers. We report results in 2408 unrelated PBSC donors prospectively evaluated by the National Marrow Donor Program (NMDP) between 1999 and 2004. Female donors had higher rates of AEs, requiring central line placement more often (17% vs 4%, P< .001), experiencing more apheresis-related AEs (20% vs 7%, P< .001), more bone pain (odds ratio [OR]=1.49), and higher rates of grades II-IV and III-IV CALGB AEs (OR=2.22 and 2.32). Obese donors experienced more bone pain (obese vs normal, OR=1.73) and heavy donors had higher rates of CALGB toxicities (>95 kg vs <70 kg, OR=1.49). Six percent of donors experienced grade III-IV CALGB toxicities and 0.6% experienced toxicities that were considered serious and unexpected. Complete recovery is universal, however, and no late AEs attributable to donation have been identified. In conclusion, PBSC collection in unrelated donors is generally safe, but nearly all donors will experience bone pain, 1 in 4 will have significant headache, nausea, or citrate toxicity, and a small percentage will experience serious short-term adverse events. In addition, women and larger donors are at higher risk for donation-related AEs.

Bone marrow harvest versus peripheral stem cell collection for haemopoietic stem cell donation in healthy donors

BACKGROUND

Haemopoietic stem cells can be collected from a donor either as a bone marrow harvest or by peripheral blood collection. Both techniques have risks for the donor.

OBJECTIVES

The aim of this review was to identify the adverse effects of haemopoietic stem cell donation and to compare the tolerability and safety of the two methods.

SEARCH STRATEGY

We searched bibliographic databases including the Cochrane Central Register of Controlled trials (CENTRAL) (The Cochrane Library 2008, issue 2), MEDLINE and EMBASE up to May 2008. We also searched reference lists of articles and contacted experts in the field.

SELECTION CRITERIA

Randomised controlled trials enrolling haemopoietic stem cell donors and evaluating the different methods of donating haemopoietic stem cells were eligible.

DATA COLLECTION AND ANALYSIS

Two authors independently screened studies for inclusion. We extracted data and evaluated methodological quality. Quantitative analysis was not possible for most outcomes, but where used we preferred random-effects models due to the variability between the included studies.

MAIN RESULTS

Six trials (807 donors) were eligible: all were substudies, or constituent parts of, larger randomised controlled trials of bone marrow and peripheral blood stem cell allogeneic transplantation. No included trial was designed solely to measure and assess the experience of stem cell donors. The donors in all studies were related to the stem cell recipient. Overall, both types of donors experienced pain subsequent to donation, and psychological morbidity. The trend was for bone marrow donors to experience more pain at the donation site, more overall adverse events, and more days of restricted activity. They were also more likely to require hospitalisation than peripheral blood stem cell donors. In contrast, peripheral blood stem cell donors experienced more pain prior to donation, which may be related to the pre-donation administration of granulocyte colony stimulating factor (G-CSF). The methodological quality of the studies was poor and indicated limitations due to the risk of selection and attrition bias. The proportion of donors from the parent trial not included in the donor substudies was also inadequately explained.

AUTHORS' CONCLUSIONS

The different short-term morbidities associated with each type of haemopoietic stem cell donation were clear, with bone marrow donors experiencing more pain and more restriction post-donation than peripheral blood donors. However, the studies were limited by their methodological quality, failure to provide long-term follow up (for which larger numbers of donors would be required) and a failure to apply consistent measures of quality of life in a way which allows more meaningful evaluation across studies.

Granulocyte colony-stimulating factor administration: adverse events

Recombinant human granulocyte colony-stimulating factor (G-CSF) has been in clinical use for approximately 2 decades. In healthy donors, it has been used to mobilize peripheral blood progenitor cells for hematopoietic stem cell transplantation and granulocytes for apheresis collection. In patients, it has been used to decrease the duration of neutropenia after chemotherapy and to offset the neutropenia due to myelodysplasia, acquired immunodeficiency syndrome, and genetic disorders of granulocyte production. As the number of uses of G-CSF in clinical practice grows, more side effects of this generally safe pharmaceutical agent are being recognized. Our objective in this article is to provide an in-depth review of the reported adverse events associated with the use of G-CSF.

Severe events in donors after allogeneic hematopoietic stem cell donation

BACKGROUND

The risk for donors of allogeneic hematopoietic stem cells transplants is generally considered negligible. Scattered reports of severe complications and a recent controversy on hematopoietic malignancies after granulocyte colony-stimulating factor administration have challenged this opinion.

DESIGN AND METHODS

Three hundred and thirty-eight allogeneic transplant teams from 35 primarily European countries were asked to report numbers of fatalities, severe adverse events and hematologic malignancies occurring among their hematopoietic stem cell donors.

RESULTS

Two hundred and sixty-two of the 338 teams (77.5%) responded to a first survey (1993-2002) and 169 of the 262 responder teams (65%) to a second survey (2003-2005). They had performed a total of 51,024 first allogeneic hematopoietic stem cell transplantations, of which 27,770 were bone marrow and 23,254 peripheral blood. They observed five donor fatalities, one after a bone marrow donation and four after peripheral blood donation (incidence 0.98 per 10,000 donations; 95% CI 0.32-2.29), 37 severe adverse events (7.25/10,000; 95% CI 5.11-9.99), of which 12 in bone marrow donors (4.32/10,000; 95% CI 2.24-7.75) and 25 in peripheral blood donors (10.76/10,000; 95% CI 6.97-15.85; p<0.05) and 20 hematologic malignancies (3.92/10,000; 95% CI 2.39-6.05), of which 8 after donating bone marrow and 12 after donating peripheral blood stem cells. The observed incidence rate of hematologic malignancies did not exceed the expected incidence in an age- and sex-adjusted general population.

CONCLUSIONS

Hematopoietic stem cell donation is associated with a small but definite risk of fatalities and serious adverse events. True incidences might be higher, due to potential underreporting by study design. A continuous, standardized donor follow-up is needed to define donor risk groups and to monitor intermediate and long-term sequelae.

Autologous infusion of expanded mobilized adult bone marrow-derived CD34+ cells into patients with alcoholic liver cirrhosis

OBJECTIVES

Recent advances in regenerative medicine, including hematopoietic stem cell (HSC) transplantation, have brought hope for patients with severe alcoholic liver cirrhosis (ALC). The aim of this study was to assess the safety and efficacy of administering autologous expanded mobilized adult progenitor CD34+ cells into the hepatic artery of ALC patients and the potential improvement in the liver function.

METHODS

Nine patients with biopsy-proven ALC, who had abstained from alcohol for at least 6 months, were recruited into the study. Following granulocyte colony-stimulating factor (G-CSF) mobilization and leukapheresis, the autologous CD34+ cells were expanded in vitro and injected into the hepatic artery. All patients were monitored for side effects, toxicities, and changes in the clinical, hematological, and biochemical parameters.

RESULTS

On average, a five-fold expansion in cell number was achieved in vitro, with a mean total nucleated cell count (TNCC) of 2.3 x 10(8) pre infusion. All patients tolerated the procedure well, and there were no treatment-related side effects or toxicities observed. There were significant decreases in serum bilirubin (P < 0.05) 4, 8, and 12 wk post infusion. The levels of alanine transaminase (ALT) and aspartate transaminase (AST) showed improvement through the study period and were significant (P < 0.05) 1 wk post infusion. The Child-Pugh score improved in 7 out of 9 patients, while 5 patients had improvement in ascites on imaging.

CONCLUSION

It is safe to mobilize, expand, and reinfuse autologous CD34+ cells in patients with ALC. The clinical and biochemical improvement in the study group is encouraging and warrants further clinical trials.