Bone Marrow and Peripheral Blood Stem Cell Harvesting

Bone Marrow Mononuclear Cell Count does not Predict Neutrophil and Platelet Recovery following Autologous Bone Marrow Transplant: Value of the Colony-Forming Unit Granulocyte-Macrophage (CFU-GM) Assay

The common use of the marrow autograft mononuclear cell (MNC) count derives from positive correlative studies following allogeneic transplantation and from earlier conflicting data regarding the value of the bone marrow autograft colony-forming unit granulocyte-macrophage (CFU-GM) assay for predicting hematologic recovery after ABMT. We conducted a retrospective analysis at our institution to determine whether autograft CFU-GM levels predict engraftment of neutrophils and platelets after ABMT in heavily pretreated patients with hematologic malignancies. Between 1 January 1993 and 1 March 1995, 58 heavily pretreated patients received only marrow cells as the autograft product. Patients with Hodgkin's disease (n = 25), acute myeloid leukemia (n = 19), and non-Hodgkin's lymphoma (n = 14) underwent intensive therapy with etoposide and melphalan. Unpurged marrow containing a minimum of 1.5 × 108/kg (range: 1.5-4.8) was infused. Median time to an absolute neutrophil count ≥0.5 × 109/L was 21 days (range 10-270) and median time to a platelet count ≥20 × 109/L independent of transfusions was 44 days (range 13-317). There was no correlation between autograft MNC count and neutrophil or platelet engraftment. However, a correlation between autograft CFU-GM and both platelet and neutrophil recovery was demonstrated with a threshold CFU-GM of 3 × 104/kg; delayed neutrophil recovery was observed in 79% of patients below this threshold compared to only 9% in those with an autograft CFU-GM level of more than 3 × 104/kg (p = 0.0001). Similarly, platelet recovery was delayed in 76% of patients below, and 20% of those above this threshold (p = 0.003). We conclude that marrow autograft CFU-GM is predictive of engraftment of both platelets and neutrophils in heavily pretreated patients after ABMT for hematological malignancies.

Micrometastases in apheresis products predict shorter progression-free and overall survival in patients with breast cancer undergoing high-dose chemotherapy (HDCT) and autologous blood stem cell transplantation (ABSCT)

The presence of cancer cells in autografts of breast cancer patients has been described to have prognostic value or directly lead to relapse. Previously, we demonstrated that apheresis products (APs) collected after induction chemotherapy have a significantly lower likelihood of tumor cell contamination. Here, we examine the prognostic value of micrometastases in autografts. Data from 83 patients with breast cancer treated with autologous blood stem cell transplantation were analyzed. Pan-cytokeratin-FITC conjugated antibodies were used to detect contaminating breast cancer cells in the APs. Progression and survival data analyzed on the basis of three or fewer cancer cells showed no significant differences in outcomes. Of the 83 patients, 11 had more than three cancer cells detectable in their APs. In total, 72 patients were shown to have less than three cells detectable. When patients with more than three cells were compared to patients with 0-3, we found statistically significant differences in progression-free survival. We also found a significant difference in overall survival (OS) between the two groups. No difference was observed in OS since the time of diagnosis. We conclude that patients with more than three contaminating cells in their APs have micrometastases and represent a poor prognosis group.

Prospective, concurrent comparison of the Cobe Spectra and Haemonetics MCS-3P cell separators for leukapheresis after high-dose filgrastim in patients with hematologic malignancies

A prospective study was undertaken to compare the mononuclear cell, CD34+ cell, and CFU-GM yields of the Haemonetics MCS-3P and the Cobe Spectra cell separators in ten patients (nine multiple myeloma and one non-Hodgkin lymphoma) on two consecutive days after mobilization with high-dose filgrastim (12-16 micrograms/k) for 4 days. All patients were harvested once on each machine, five starting on each machine. The target duration of the procedure on the Spectra was 160 minutes, and the target blood volume processed on the MCS-3P was 60-70 ml/kg body weight. Both machines were operating on the 1995 software versions supplied by the respective manufacturers. The time taken for the procedure was significantly longer with the Haemonetics machine. The volumes of blood processed and the product collected were significantly higher with the Spectra, as were the absolute mononuclear and CD34+ cell yields, and yields per unit time. Mononuclear and CD34+ cell yields per unit volume of blood processed were comparable for both machines. The differences in CFU-GM yields were not significant, largely because of wide interpatient variations. The extent of platelet depletion as a result of the procedure was greater with the Spectra because of the higher blood volume being processed. We conclude that the Cobe Spectra is a significantly faster machine than the Haemonetics MCS-3P; and consequently, its use is associated with higher mononuclear and CD34+ cell yields.

Allogeneic blood and bone-marrow stem-cell transplantation in haematological malignant diseases: a randomised trial

BACKGROUND

Autologous transplantation with peripheral blood stem cells (PBSC) results in faster haematopoietic-cell repopulation than with bone marrow. We prospectively compared bone marrow and PBSC for allogeneic transplantation.

METHODS

Adult HLA-identical sibling donors provided bone marrow and lenograstim-mobilised PBSC. 39 patients with malignant haematological disorders were infused with either bone marrow (n=19) or PBSC (n=20) after standard conditioning regimens in a double-blind, randomised fashion. The identity of the infused products for all patients remained masked until 1 year after the last patient had received transplantation.

FINDINGS

The PBSC group had significantly faster neutrophil recovery to 0.5x10(9)/L (median 17.5 vs 23 days, p=0.002), and platelet recovery to 20x10(9)/L (median 11 vs 18 days, p<0.0001) and to 50x10(9)/L (median 20.5 vs 27 days, p=0.02) than the bone-marrow group. PBSC patients were discharged from hospital earlier than were bone-marrow patients (median 26 vs 31 days, p=0.01). At 4 weeks after transplantation, absolute lymphocytes (0.48 vs 0.63, p=0.08) and CD25 cells (0.04 vs 0.08, p=0.007) were higher in the PBSC group, and the proportion of patients with absolute lymphopenia (74% vs 33%, p=0.03) and CD4 lymphopenia (59% vs 24%, p=0.05) was significantly higher in the bone-marrow group. There was no significant difference in the occurrence of acute or chronic graft-versus-host disease and overall survival. The probability of relapse was significantly higher in the bone-marrow group than in the PBSC group (p=0.01); all five relapses occurred among bone-marrow recipients.

INTERPRETATION

Our small study indicates that PBSCs are better than bone marrow for allogeneic transplantation from HLA-identical siblings in terms of faster haematopoietic and immune recovery, and have the potential to reduce disease recurrence.

Comparison of marrow and blood cell yields from the same donors in a double-blind, randomized study of allogeneic marrow vs blood stem cell transplantation

Forty healthy adult donors underwent marrow (BM) as well as peripheral blood (PBSC) stem cell collections for their HLA-identical adult siblings with hematologic malignancies. BM was harvested on day 1 (target 3 x 108 nucleated cells/kg, 10 microg/kg lenograstim (glycosylated G-CSF) administered on days 2-6, and a single leukapheresis performed on day 6. The blood volume processed was the higher of 200% donor blood volume or 10 liters. The total nucleated cell (TNC) yields from PBSC were 1.1- to 4.3-fold higher than BM (median 7.0 vs 3.1 x 10(8)/kg, P < 0.0001). Although BM contained a higher proportion of CD34+cells (1.3% vs 0.7%, P < 0. 0001) and a comparable proportion of CD3+ cells (median 29% vs 26%, P = 0.4), the absolute numbers of CD34+ and CD3+ cells and their subsets were several times higher in PBSC. There was a poor correlation between BM and PBSC CD34 and TNC numbers, but a significant correlation between BM and PBSC CD3 numbers. Only five of 40 BM harvests contained >/=2 x 10(6) CD34+ cells/kg compared with 35 of 40 PBSC harvests (P < 0.0001). We conclude that the numbers of progenitor and immunocompetent cells in PBSC are several times higher than in BM. It is possible to collect adequate numbers of progenitor cells from blood after lenograstim stimulation more frequently than from marrow, and donors yielding low quantities of progenitor cells from BM usually deliver better quantities from PBSC. Bone Marrow Transplantation (2000) 25, 501-505.

Bone marrow processing using the fenwal CS-3000 plus blood cell separator: results of 99 procedures

BMT is used as an established therapy for patients with malignant and nonmalignant diseases. Many techniques for ex vivo treatment have been developed, but these techniques must be preceded by BM processing. We report our experience in processing 99 BM using the Fenwal CS-3000 Plus cell separator using the 1-special program. Ninety-nine procedures were performed in BM harvested from 73 patients and 26 healthy donors. The number of nucleated cells (NC), mononuclear cells (MNC), RBC, platelets, colony-forming units-granulocyte-macrophage (CFU-GM), CD34+ cells, relative purity of MNC and PMN, and volume were determined in the unprocessed BM and in the final product. BM processing resulted in NC, MNC, CFU-GM, and CD34+ cell recoveries of 31%, 82.2%, 117.6%, and 97.8%, respectively. RBC, PMN, platelets, and volume removal, respectively, were 96%, 92%, 37.2%, and 85.1%. In pediatric patients, the volume reduction was significantly lower than in adult patients (79.6% versus 88.8%). No other significant differences were found between pediatric and adult results. We conclude that BM processing with the Fenwal CS-3000 Plus cell separator provides a product that can undergo further ex vivo treatments or cryopreservation.

CD34 antigen: molecular features and potential clinical applications

Despite the wide variety of functions exhibited by mature peripheral blood cells, all are derived from a small pool (1-3%) of primitive precursor cells in the bone marrow (BM) that bear a unique surface glycoprotein, CD34. Isolated CD34+ cells are capable of reconstituting all hematopoietic lineages, both in experimental animals and in humans following intensive therapy. CD34+ cells capable of reconstituting hematopoiesis are also found at low frequency in peripheral blood (PB), a frequency which can be dramatically increased by combinations of chemotherapy and recombinant cytokines. In some cases, PB "stem cells" (PBSC) can be used to augment or even replace conventional BM autografts. The availability of CD34 antibodies has greatly aided the development of techniques for the enrichment of primitive progenitor cells, thus allowing studies of the hematopoietic potential of stem cells in vitro. Additionally, the use of CD34 antibodies for the "positive selection" of hematopoietic stem/progenitor cells from tumor-contaminated marrow may possibly represent an alternative "purging" strategy prior to transplantation. The availability of pure populations of the most primitive hematopoietic progenitor cells will also facilitate study of genetic manipulation as a practical therapeutic modality.