PubMed Health⌕ Search

Biomedical subjects

E M Areman

Publications and source records attributed to E M Areman.

11 recordsLinked to original sources
PubMed1994

The impact of harvest center on quality of marrows collected from unrelated donors.

The total number and distribution of nucleated cells in harvested bone marrow are potentially important determinants of patient outcome following bone marrow transplantation. In order to assess whether marrows collected from predominantly unrelated donors at Georgetown University Medical Center (GUMC) were different in cellular content from marrows collected at harvest centers outside of GUMC, we compared the nucleated cell counts and mononuclear cell subset distribution (CD34, CD3, CD4, CD8, CD19 antigen-positive cell content) of 10 consecutive marrows harvested at GUMC to 10 unrelated donor marrows from outside harvest centers. Significantly higher nucleated cell counts and CD34 antigen-positive cell content and significantly lower CD3 and CD4 antigen-positive T-cell numbers were demonstrated among the marrows harvested at GUMC. These results confirmed significant variability in marrow collection practices between GUMC and 10 different outside harvest centers and suggest that strict adherence to a specific collection procedure, involving small volume marrow aspirations and multiple puncture sites, results in a product with a high number of early hematopoietic progenitor cells and minimal contamination by peripheral blood. These data further suggest the need for careful monitoring of individual unrelated donor marrow collection centers' practices to optimize the quality of the harvested marrow.

Academic Medical Centers↗
PubMed1991

Bone marrow processing for transplantation.

As indications for BMT increase, so do variations in bone marrow processing and manipulation techniques. Many centers have their own unique methods of mononuclear cell purification, concentration and storage. This is particularly evident in the processing of bone marrow for autologous BMT to allow dose intensification as salvage therapy for malignant disease. Unique procedures have been developed to maximize yields, concentrate mononuclear cells necessary for engraftment, and reduce the likelihood of GVH disease. Graft rejection and disease relapse still remain a problem in some of these "manipulated" marrows. Newer procedures may allow titration of the optimum numbers of immune reconstituting cells; however, at this time, these techniques are not precise and the balance between preventing GVH disease at the expense of graft failure or relapse may still jeopardize disease-free survival. Innovative purging techniques that include pharmacologic and immunologic methods, continue to evolve, necessitating standards for bone marrow processing that are flexible yet practical. Quality control and viability assays are essential to verify the biologic proliferative potential of progenitor cells capable of marrow reconstitution. Although no standards are yet established, all centers should have criteria to monitor the quality of the processed marrow. Blood banks and transfusion services are well versed in regulations governing processing, labeling, storage, and quality control of blood components. Bone marrow is the ultimate blood component, and it stands to reason that methods outlined in this article be integrated into transfusion medicine.

Blood Component Transfusion↗
PubMed1991

Automated processing of human bone marrow can result in a population of mononuclear cells capable of achieving engraftment following transplantation.

A concentrate of mononuclear bone marrow cells is often desired for ex vivo treatment with pharmacologic agents, monoclonal antibodies, cytokines, and other agents prior to transplantation. A method has been developed for automated separation of mononuclear cells from large volumes of harvested bone marrow. A programmable instrument originally designed for clinical ex vivo cell separation and the plasma-pheresis of patients and blood donors was adapted to permit rapid preparation, in a closed sterile system, of a bone marrow product enriched with mononuclear cells. A mean (+/- SEM) of 53 +/- 30 percent of the original mononuclear cells was recovered in a volume of 125 +/- 42 mL containing 82 +/- 12 percent mononuclear cells. This technique removed 95 +/- 9 percent of the red cells in the original marrow. No density gradient materials or sedimenting agents were employed in this process. Of 36 marrows processed by this technique, 19 autologous (6 of which were purged with 4-hydroperoxycyclophosphamide) and 7 allogeneic marrows have been transplanted, with all evaluable patients achieving a neutrophil count of 0.5 x 10(9) per L in a mean (+/- SEM) of 21 +/- 6 days.

Bone Marrow Cells↗
PubMed1990

Processing and storage of human bone marrow: a survey of current practices in North America.

We conducted a two-step survey to question 110 transplant centers in the United States and Canada regarding marrow processing and storage policies and procedures. Approximately 65% of the centers surveyed responded to the questionnaires. Major differences with respect to patient diagnoses, amount of marrow harvested, purging method applied, freezing procedure, storage bag, cell concentrations, storage duration, interval until transplantation, cell counting, viability determination and so forth were reported. Among those centers responding 13% stored not only autologous but also allogeneic marrow. There was no consensus regarding patient consent for duration of storage, coverage of cost for cryopreservation or utilization of stored marrow after a patient's death. Additional studies will be necessary to correlate in vitro methods of marrow storage with clinical transplantation results, and to determine the cost/benefit ratio of this approach to various diagnoses. This should provide the basis for the establishment of standards and should facilitate the approach to various ethical questions.

Bone Marrow↗
PubMed1990

Automated isolation of mononuclear cells using the Fenwal CS3000 blood cell separator.

We describe a method for in vitro isolation of mononuclear cells from peripheral blood or bone marrow using a Fenwal CS3000 Apheresis device without employing density gradients or sedimenting agents. The automatic processing program requires minimal operator intervention and no subjective operator decisions. A mean of 67% of starting mononuclear cells were recovered in a 100 ml product having 95% mononuclear cells and less than 1% of the original red blood cells. The average processing time was 35 minutes.

Bone Marrow Cells↗
PubMed1990

Cryopreservation and storage of human bone marrow: a survey of current practices.

As bone marrow transplantation is being used with increasing frequency, problems of storage space and cost, inventory control and disposal have arisen. Issues such as maximum storage time and acquisition of consent for marrow disposal need to be addressed before a large inventory is accumulated. Consideration should also be given to using non-infused marrows for research purposes. Eighty-three bone marrow transplant centers were surveyed in an attempt to establish a data base with regard to guidelines for storage of cryopreserved human bone marrow. Fifty-two centers (62.7%) responded to the questionnaire, 5 of which did not have an active cryopreservation program. The remaining 47 centers freeze and store autologous marrow from patients with leukemia, lymphoma, neuroblastoma and a large diversity of other conditions including solid tumors. Twelve centers (25.5%) specify maximum storage times of up to 5 years, but only 9 centers (19.1%) require the donor to sign a specific consent form for marrow disposal if it is not used for transplantation within a given time. Eighty-five percent of the responding centers reinfuse at least half of the marrows they freeze within 12 months of harvesting. It appears that at least 90% of marrows that are being reinfused have been stored for three years or less. However, the storage time of non-infused marrows extends even further, and autologous marrow has been reinfused successfully as long as eight years after storage.

Bone Marrow Transplantation↗
PubMedDate not supplied

Bulk cryopreservation of lymphocytes in glycerol.

The authors describe a method for freezing large amounts of peripheral blood lymphocytes (PBL) in a 20 percent glycerol solution. Between 0.6 and 4.3 X 10(9) cells in autologous plasma were frozen in polyethylene freezing bags in a final volume of 50 ml. The recovery after thawing averaged 89 +/- 14 percent with a mean viability by trypan blue dye exclusion of 80 +/- 7 percent (n = 11). In aliquots of fresh and frozen-thawed PBL from the same subjects radiolabeled with 111In, the radiolabeling efficiency for both fresh and thawed cells was 49 +/- 15 percent (p = 0.98, n = 5). The mitogen mean stimulation indices for glycerol-frozen cells (471 with phytohemagglutinin-M, 176 with pokeweed mitogen, and 380 with concanavalin A) were superior to those of cells frozen by a standard technique with dimethylsulfoxide (DMSO) (141, 47, and 123; p less than 0.05) and comparable to those of fresh PBL (403, 75, and 147). In a mixed lymphocyte culture, glycerol-frozen PBL showed significantly greater responsiveness to a pool of stimulator cells than did PBL frozen in DMSO (p = 0.03). Thawed cells are viable and functional as demonstrated by their response to mitogens and their ability to stimulate and respond in mixed lymphocyte culture.

Blood Preservation↗