Marrow storage techniques: a clinical comparison of refrigeration versus cryopreservation

Non-cryopreserved autologous peripheral blood stem cell transplantation for multiple myeloma and lymphoma in countries with limited resources: practice considerations from the Worldwide Network for Blood and Marrow Transplantation

Autologous peripheral blood stem cell (PBSC) transplantation is a standard treatment of multiple myeloma (MM), Hodgkin lymphoma and various subtypes of non-Hodgkin lymphoma. Cryopreservation of hematopoietic stem cells is standard practice that allows time for delivery of conditioning regimen prior to cell infusion. The aim of this Worldwide Network for Blood & Marrow Transplantation (WBMT) work was to assess existing evidence on non-cryopreserved autologous transplants through a systematic review/meta-analysis, to study feasibility and safety of this approach. We searched PubMed, Web of Science and SCOPUS for studies that utilized non-cryopreserved autologous PBSC transplantation. Identified literature was reviewed for information on mobilization, apheresis, preservation and viability, conditioning regimen, engraftment, response, and survival. Results highlight collective experience from 19 transplant centers (1686 patients), that performed autologous transplants using non-cryopreserved PBSCs. The mean of infused CD34+ was 5.6 × 106/kg. Stem cell viability at transplantation was >90% in MM and >75% in lymphomas, after a storage time of 24-144 h at +4 °C. Mean time-to-neutrophil engraftment was 12 days and 15.3 days for platelets. Pooled proportion estimates of day 100 transplant-related mortality and graft failure were 1% and 0%, respectively. Non-cryopreservation of apheresed autologous PBSCs appears feasible and safe.

Long-term storage of peripheral blood stem cells frozen and stored with a conventional liquid nitrogen technique compared with cells frozen and stored in a mechanical freezer

BACKGROUND

Cryopreservation of hematopoietic progenitor cells using liquid nitrogen and controlled-rate freezing requires complex equipment and highly trained staff and is expensive. We compared the liquid nitrogen method with methods using a combination of dimethyl sulfoxide (DMSO) and hydroxyethyl starch (HES) for cryopreservation followed by storage in mechanical freezers.

STUDY DESIGN AND METHODS

Peripheral blood stem cells (PBSCs) were collected from normal donors by apheresis and allocated to one of four preservation and storage conditions: 1) 10% DMSO with freezing in liquid nitrogen and storage in liquid nitrogen, 2) 5% DMSO and 6% HES with freezing and storage in a -80 degrees C mechanical freezer, 3) 5% DMSO and 6% HES with freezing in a -80 degrees C mechanical freezer and storage in a -135 degrees C mechanical freezer, or 4) 5% DMSO and 6% HES with freezing and storage both in a 135 degrees C mechanical freezer. Cells were stored for 5 years during which total nucleated cells (TNCs), cell viability, CD34+ cell content, and colony-forming unit-granulocyte-macrophage content were determined.

RESULTS

There were some significant differences in the variables measured during freezing and the 5 years of storage compared to the values before freezing and storage; however, these differences were not consistent and do not favor one protocol over the others. Samples stored for 24 hours before cryopreservation showed a significant decrease in TNCs, but no other significant changes during the 5 years.

CONCLUSION

In vitro measurements indicate that PBSCs can be successfully frozen and stored using a combination of DMSO and HES providing smaller amounts of DMSO and allowing simplified freezing and storage conditions.

Feasibility and safety of autotransplants with noncryopreserved marrow or peripheral blood stem cells: a systematic review

The objective of this systematic review is to examine the feasibility and safety of autologous noncryopreserved stem-cell transplants. This technique avoids the cost of establishing and maintaining a cryopreservation facility and may be of value for transplant centers in regions with limited economic resources. The primary outcome was the graft failure rate. In addition, a detailed description of the high-dose therapy regimens employed was undertaken. Secondary outcomes were transplant-related mortality and neutrophil and platelet engraftments times. Sixteen well-conducted nonrandomized studies met the eligibility criteria. Only two cases of graft failure (0.36%) occurred among 560 assessable patients receiving high-dose therapy and autotransplant for non-Hodgkin's lymphoma, Hodgkin's lymphoma, multiple myeloma, germ-cell tumors and acute leukemias. The most traditional high-dose schedules were used, although often modified to shorter regimens. High-dose melphalan appeared especially useful given its short half-life and was used to treat multiple myeloma by most groups. Secondary outcomes were comparable to those reported in the most relevant studies addressing standard (cryopreserved) autotransplant. According to this study, the use of autologous noncryopreserved hematopoietic progenitors to support patients undergoing high-dose therapy is feasible and safe.

Cyclophosphamide, etoposide and carboplatine plus non-cryopreserved autologous peripheral blood stem cell transplantation rescue for patients with refractory or relapsed non-Hodgkin's lymphomas

A simplified schedule of high-dose chemotherapy consisting of cyclophosphamide (60 mg/kg/day for 2 days), etoposide (15 mg/kg/day for 2 days) and carboplatine (400 mg/m(2)/day for 2 days), together with autologous non-cryopreserved peripheral blood stem cells was used for treatment of relapsed (29 patients) and refractory (three patients) patients with non-Hodgkin's lymphoma (NHL). The use of such granulocyte colony-stimulating factor (G-CSF)-mobilized peripheral blood stem cells (PBSC) after high-dose myeloablative therapy resulted in a rapid, complete and sustained hematopoietic recovery. The median time to achieve an absolute neutrophil count greater than 0.5 x 10(9)/l was 12 days (range 8-17 days). The median time to self-sustained platelet count greater than 20 x 10(9)/l was 14 days (range 7-19 days). Fifteen of the 32 patients (49%) were alive and disease free at a median follow-up of 18 months (range 10-96 months) for all surviving patients. The estimated 2-year overall survival (OS) and disease free survival (DFS) for all patients were 50 and 43%, respectively. Twelve patients died of relapse or progressive disease, two patients died of infection and one patient died of cardiac cause. The median time to relapse was 12 months (5-27) from PBSC infusion. High-dose chemotherapy with short-duration chemotherapy and non-cryopreserved bone marrow (BM) is an effective and safe treatment modality for patients with relapsed or resistant NHL.

Hematologic reconstitution following high-dose and supralethal chemoradiotherapy using stored, noncryopreserved autologous hematopoietic stem cells

Although cryopreservation is the standard for autotransplantation, it has logistic and financial disadvantages in undeveloped countries such as Colombia. In 47 patients, peripheral blood was refrigerated at 4 degrees C up to 144 h before autotransplantation. For mobilization, 27 men and 20 women of median age 37 years affected with hematologic malignancies received G-CSF. The 17 patients in Group 1 showed pre-refrigeration CFU-GM of 2.62 x 10(5)/kg (range 0.36 to 16.6 x 10(5)/kg) and at re-infusion, 1.36 x 10(5)/kg (range 0 to 6.32 x 10(5)/kg) of 83% viability (range, 78% to 96%). These patients showed >0.5 x 10(9)/L granulocytes on day +11 (range, 9 to 15) and >20 x 10(9)/L platelets on day +16 (range, 11 to 44). The 25 patients in Group 2 showed CD34 of 3.9 x 10(6)/kg (range, 0.16 to 9 x 10(6)/kg) and mononuclear cell count (MNC) of 8.7 x 10(8)/kg, reaching >0.5 x 10(9)/L granulocytes at day +13 (range, 10 to 17) and >20 x 10(9)/L on day +15 (range, 14 to 20). Among the 5 patients in Group 3, the average of MNC of 12.7 x 10(8)/kg was reached and >0.5 x 10(9)/L granulocytes on day 11 (range, 10 to 16) and >20 x 10(9)/L on day 14 (range, 10 to 18). No differences were observed between the groups. Refrigeration of stem cells appears to be a simple, effective, and inexpensive method that should be considered for autotransplants within a few days of harvesting when resources are limited for long-term storage.

An optimization of isolation of early hematopoietic cells from heparinized cadaveric organ donors

Heparinized cadaveric organ donors are a potential source of hematopoietic cells for transplantation purposes. The aim of this study was to optimize the harvest of early hematopoietic cells from cadaver donors. Accordingly, we noticed that bone marrow cells harvested from cadaver donors should be resuspended in RPMI or Iscove's medium supplemented with heparin or ACD. Bags with harvested marrow should contain 20% atmosphere air during short-term storage/transportation. Finally, we noticed that BMMNC survive short-term storage better if the collected marrow is not depleted of erythrocytes.

Non-cryopreserved peripheral blood progenitor cells collected by a single very large-volume leukapheresis: a simplified and effective procedure for support of high-dose chemotherapy

High-dose chemotherapy with autologous peripheral blood progenitor cell (PBPC) support has become a widely used treatment strategy. In order to simplify the procedure, a single very large-volume leukapheresis programme combined with short-term refrigerated storage of the PBPC was developed. Seventy-two patients suffering from various relatively chemosensitive malignancies received high-dose chemotherapy, consisting of agents with short in vivo half-lives and 24 to 48 hours later, the refrigerated PBPC were reinfused. A single very large-volume apheresis was sufficient to obtain at least 2 x 10(6)/kg CD34+ cells in 58 patients (81%), and 63% had at least 2.5 x 10(6) CD34+ cells/kg. Only two patients (3%) were transplanted with less than 1 x 10(6) CD34+ cells/kg. In three patients (4%) leukapheresis was repeated because of insufficient number of PBPC. The median CD34+ cell count was 3 x 10(6)/kg. A median of 38.5 L blood (range, 21 to 59) was processed, which accounted for a median of 9 x patient's total blood volume. Very large-volume leukapharesis was well tolerated with symptomatic hypocalcemia being the most common (18%) side-effect. The median time to neutrophils >1.5 x 10(9)/L, and to self-supporting platelet count >25 x 10(9)/L, was 10 and 12 days after reinfusion of PBPC graft, respectively. There were no treatment-related deaths. Our results indicate that this simplified approach of PBPC transplantation can be associated with prompt hematologic recovery in most patients and that it can be useful in settings where facilities are limited or for certain diseases where conditioning regimens with short half-life are appropriate. J. Clin. Apheresis, 15:236-241, 2000.

Growth factor stimulation of cryopreserved CD34+ bone marrow cells intended for transplant: an in vitro study to determine optimal timing of exposure to early acting cytokines

Stimulating CD34+ hematopoietic cells with growth factors prior to transplantation may decrease the duration of post-transplant aplasia. The optimal time in which to deliver this stimulus remains unclear. We therefore sought to determine if progenitor cell cloning efficiency, as reflected by colony forming units-granulocyte-macrophage (CFU-GM) colony formation, differed when growth factor stimulation was carried out prior to freezing or after thawing. To address this issue, CD34+ marrow cells were suspended in Iscove's medium with 20% bovine calf serum. They were then stimulated with kit ligand (KL), interleukin-3 (IL-3), and interleukin-1 beta (IL-1 beta) for 36 h either prior to cryopreservation or immediately after thawing. We observed that cells stimulated prior to freezing formed more CFU-GM colonies than cells stimulated after thawing. We also found that CD34+ cells stimulated with growth factors either before or after freezing gave rise to more CFU-GM colonies than thawed cells plated without prestimulation. Thus, the cloning efficiency of stored marrow, as reflected by CFU-GM colony formation, may be effectively enhanced by pretreating cells with hematopoietic growth factors. Our data further suggest that the optimal time for this treatment is before cryopreservation as opposed to immediately after thawing.(ABSTRACT TRUNCATED AT 250 WORDS)

Peripheral blood progenitor cells versus bone marrow

Transplantation of mobilized peripheral blood progenitor cells has generally produced shortening of the period of posttransplant aplasia that is characteristic of bone marrow grafts. However, there has been no large prospective randomized study to compare these two sources of hematopoietic cells or to determine their relative merits. This issue is explored in this review.

What really cures in autologous bone marrow transplantation? A possible role for dimethylsulfoxide

Dimethylsulfoxide has long been known to be a potent inducer of differentiation of various malignant cells in animals and human beings. It is a toxic agent, and high concentrations are needed to induce differentiation. Other compounds that also have methylene groups and a polar/apolar architecture, and are needed in much smaller concentrations to induce differentiation, like hexamethylene bisacetamide have been developed. They are already used in trials in human beings. However dimethylsulfoxide still has a very important role in bone marrow transplantation, being added to the frozen marrow as a cryoprotectant. We suggest that dimethylsulfoxide may induce differentiation of malignant cells present in the marrow or alternatively in the body when it is infused back with the transplanted marrow. This may be an additional factor contributing to the success rate achieved in various malignancies treated by transplantation, especially autologous, complementing the traditional explanations which are based mainly on the high dose chemotherapy and the immunological manipulations that occur during transplantation.

The Regulation of Hematopoietic Stem Cell Collection and Storage: The New York State Approach

In December 1988, the New York State (NYS) regulatory code on bone marrow banking went into effect. The goals of the regulations were to codify a high standard of practice, to prohibit charlatanism in the practice or promotion of stem cell banking, and to promote legitimate research. The NYS approach modeled the stem cell regulatory language after that already established for blood banks and clinical laboratories. Also, the stem cell standards are an element of standards applicable to all tissue banks, developed as a result of a comprehensive transplant law enacted in NYS in 1990. The code itself, published as an addendum to this article, mandates that a qualified (by training and experience) medical director and medical advisory committee be appointed, and gives broad and complete responsibility for the services provided to that medical director. Explicit written policies and procedures regarding administrative, technical, safety, and quality issues are necessary, but regulatory micromanagement of the laboratory was avoided by limiting detailed procedural requirements. We believe that these regulations have contributed to the quality and safety of stem cell-related therapies in NYS.