Mobilization, collection, and transplantation of peripheral blood hematopoietic progenitor cells in a patient with multiple myeloma and hemoglobin SC disease

Red blood cell exchange in patients with sickle cell disease-indications and management: a review and consensus report by the therapeutic apheresis subsection of the AABB

BACKGROUND

A prior practice survey revealed variations in the management of patients with sickle cell disease (SCD) and stressed the need for comprehensive guidelines. Here we discuss: 1) common indications for red blood cell exchange (RCE), 2) options for access, 3) how to prepare the red blood cells (RBCs) to be used for RCE, 4) target hemoglobin (Hb) and/or hematocrit (Hct) and HbS level, 5) RBC depletion/RCE, and 6) some complications that may ensue.

STUDY DESIGN AND METHODS

Fifteen physicians actively practicing apheresis from 14 institutions representing different areas within the United States discussed how they manage RCE for patients with SCD.

RESULTS

Simple transfusion is recommended to treat symptomatic anemia with Hb level of less than 9 g/dL. RCE is indicated to prevent or treat complications arising from the presence of HbS. The most important goals are reduction of HbS while also preventing hyperviscosity. The usual goals are a target HbS level of not more than 30% and Hct level of less than 30%.

CONCLUSION

Although a consensus as to protocol details may not be possible, there are areas of agreement in the management of these patients, for example, that it is optimal to avoid hyperviscosity and iron overload, that a target Hb S level in the range of 30% is generally desirable, and that RCE as an acute treatment for pain crisis in the absence of other acute or chronic conditions is ordinarily discouraged.

Plerixafor enables safe, rapid, efficient mobilization of hematopoietic stem cells in sickle cell disease patients after exchange transfusion

Sickle cell disease is characterized by chronic anemia and vaso-occlusive crises, which eventually lead to multi-organ damage and premature death. Hematopoietic stem cell transplantation is the only curative treatment but it is limited by toxicity and poor availability of HLA-compatible donors. A gene therapy approach based on the autologous transplantation of lentiviral-corrected hematopoietic stem and progenitor cells was shown to be efficacious in one patient. However, alterations of the bone marrow environment and properties of the red blood cells hamper the harvesting and immunoselection of patients' stem cells from bone marrow. The use of Filgrastim to mobilize large numbers of hematopoietic stem and progenitor cells into the circulation has been associated with severe adverse events in sickle cell patients. Thus, broader application of the gene therapy approach requires the development of alternative mobilization methods. We set up a phase I/II clinical trial whose primary objective was to assess the safety of a single injection of Plerixafor in sickle cell patients undergoing red blood cell exchange to decrease the hemoglobin S level to below 30%. The secondary objective was to measure the efficiency of mobilization and isolation of hematopoietic stem and progenitor cells. No adverse events were observed. Large numbers of CD34⁺ cells were mobilized extremely quickly. Importantly, the mobilized cells contained high numbers of hematopoietic stem cells, expressed high levels of stemness genes, and engrafted very efficiently in immunodeficient mice. Thus, Plerixafor can be safely used to mobilize hematopoietic stem cells in sickle cell patients; this finding opens up new avenues for treatment approaches based on gene addition and genome editing. Clinicaltrials.gov identifier: NCT02212535.

Difficulties in hematopoietic progenitor cell collection from a patient with TEMPI syndrome and severe iatrogenic iron deficiency

BACKGROUND

Collection of hematopoietic progenitor cells by apheresis (HPC-A) requires separation of cells by density. Previous studies highlighted the challenges of HPC-A collection from patients with abnormal red blood cells (RBCs). TEMPI syndrome is a recently described condition defined by teleangiectasias, elevated erythropoietin and erythrocytosis, monoclonal gammopathy, perinephric fluid collections, and intrapulmonary shunting. Patients with TEMPI syndrome have responded to therapies used to treat plasma cell dyscrasias and may benefit from autologous HPC transplantation. We report HPC-A collection from a patient with TEMPI syndrome that was complicated by severe iron deficiency.

STUDY DESIGN AND METHODS

The patient received granulocyte-colony-stimulating factor (G-CSF) and plerixafor for HPC mobilization and underwent 3 days of HPC-A collection.

RESULTS

The patient presented for collection with a microcytic erythrocytosis. Over 3 days, approximately 50 L of whole blood was processed, and 2 × 10(8) CD34+ cells were collected (2.8 × 10(6) CD34+ cells/kg). The mean collection efficiency (CE), percentage of mononuclear cells, hematocrit (Hct), and RBC count were 18%, 90%, 14%, and 9 × 10(11) , respectively. Altering collection variables to avoid RBC contamination reduced CE. Ficoll preparations of the products after freeze-thaw showed RBC contamination and hemolysis. Postthaw viability exceeded 95%. The products were not RBC reduced or washed. There were no adverse reactions during or after infusion.

CONCLUSIONS

HPC-A collection from a patient with TEMPI syndrome was complicated by microcytic erythrocytosis, leading to RBC contamination and hemolysis in the product. Adequate HPCs were collected and the patient tolerated infusion without RBC depletion or washing. Our report highlights difficulties of HPC-A collection from iron-deficient patients.

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.

Safety of pegfilgrastim (neulasta) in patients with sickle cell trait/anemia

Pegfilgrastim (Neulasta) is a recombinant filgrastim (human granulocyte colony-stimulating factor (G-CSF)) attached to a polyethylene glycol (PEG) molecule and is given as part of chemotherapy regimens that are associated with significant myelosuppression and risk for febrile neutropenia. Prescribing information available on manufacturer's website for the drug warns us about possible severe sickle cell crises related to the medication but does not report the actual incidence or the use in patients with sickle cell trait. Caution is advised when using it in patients with sickle cell disease. Here we present a case of a Caucasian female with known sickle cell trait (SCT) with no prior complications who developed a presumed sickle cell crisis after getting Neulasta, as a part of the chemotherapy regimen used to treat her breast cancer. Based on our literature review, this appears to be the first case report of a patient with SCT developing a sickle cell crisis with the pegylated form of recombinant filgrastim. Given the dearth of literature regarding the use of G-CSF and its related pegylated forms in patients with sickle cell anemia and sickle cell trait, a discussion of potential mechanisms and review of current literature and guidelines is also presented.

Granulocyte colony-stimulating factor (G-CSF) administration in individuals with sickle cell disease: time for a moratorium?

Granulocyte colony-stimulating factor (G-CSF) is used commonly in an attempt to reduce the duration of neutropenia and hospitalization in patients undergoing chemotherapy and to obtain hematopoietic stem cells (HSC) for transplantation applications. Despite the relative safety of administration of G-CSF in most individuals, including subjects with sickle cell trait, severe and life-threatening complications have been reported when used in individuals with sickle cell disease (SCD), including those who were asymptomatic and undiagnosed prior to administration. The administration of G-CSF has now been reported in a total of 11 individuals with SCD. Seven developed severe adverse events, including vaso-occlusive episodes, acute chest syndrome, multi-organ system failure and death. Precautions, including minimizing the peak white blood cell count, dividing or reducing the G-CSF dose and red blood cell transfusions to reduce sickle hemoglobin (HbS) levels, have been employed with no consistent benefit. These reported data indicate that administration of G-CSF in individuals with SCD should be undertaken only in the absence of alternatives and after full disclosure of the risks involved. Unless further data demonstrate safety, routine usage of G-CSF in individuals with SCD should be avoided.