Society for Cryobiology Abstract Submission Template IMPORTANT 1) Please ensure that you have filled out the Title, Authors, Affiliations, Contact email and Abstract sections. 2) The maximum number of words allowed in your entire abstract is 500 words. This does not include the Title, Authors and Affiliations. 3) Figures, tables and subheadings are NOT allowed. 4) Authors must declare at the bottom of the abstract any actual or potential conflicts of interest. 5) The source of funding must be declared at the bottom of the abstract. 6) Provide any acknowledgments at the end of your abstract. 7) Cited references should be included in the body of the text, and NOT listed at the end. 8) Use the abbreviation Me2SO, not DMSO. 9) Save the completed document for upload using Microsoft Word 2003 or a lower version. Do NOT submit templates saved in Word “docx” OpenXML format, as these cannot be processed. 10) Abstracts of oral and poster presentations given at the meeting will be published in the December issue of Cryobiology – Vol. 65 (3).
Title (The title should be in bold type followed by one return) Peripheral blood derived hematopoietic progenitor cells (HPC): An overview of a successful application of cryobiology
Authors (Authors should be in normal type followed by one return. Presenter must be marked * in
front of his/her name and the corresponding author must underline her/his name in the list of authors)
*Andreas Sputtek1, Evgeny Klyuchnikov2; Nikolaus Kröger3, Sven Peine 1, Arthur W. Rowe 3
Affiliations (ALL authors’ affiliations should be in italic type followed by one return) 1
Department of Transfusion Medicine, University Medical Center HamburgEppendorf, Hamburg, Germany 2 Clinic for Stem Cell Transplantation, University Medical Center Hamburg-Eppendorf, Hamburg, Germany 3 New York University School of Medicine, New York, NY, USA
Contact email (The journal would like to include the email address of the corresponding authors of abstracts published in Cryobiology. Please give the email address if you are happy to see this published with your abstract)
[email protected]
Abstract body
IMPORTANT: Your abstract text must fit into the box provided. The font should be Arial 12pt with
single-line spacing. You may alter these values only to add symbols or superscripts, etc. Use Symbol font for Greek and other special characters. Do NOT include tables, figures or references. These will be removed before your abstract is published.
Hematopoietic progenitor cells (HPC) are primitive pluripotent cells capable of self renewal as well as of differentiation and maturation into all hematopoietic lineages. They can be found in bone marrow, in fetal liver, in umbilical cord blood, and in the mononuclear cell fraction of circulating blood. They are characterized by their colonyforming capacities in different in vitro cell culture assays and by the surface antigen marker CD34. Today, HPC are successfully cryopreserved using methods based on a dimethyl sulphoxide (Me2SO) method proposed by Ashwood-Smith (1961) for bone marrow. Cryopreserved peripheral HPC (in combination with patient high-dose chemotherapy or irradiation) have become a “standard” blood component for the treatment of several malignant diseases in more than 10,000 patients in Europe per year, e.g. lymphoma, myeloma, leukemia, and germ cell tumors. Nowadays HPC are usually obtained by apheresis from peripheral blood after stimulation with a cytokine named G-CSF (granulocyte colony stimulating factor). During cooling, heat is removed either by computer-controlled and liquid nitrogen (LN2) operated machines or in mechanical (–80 °C) refrigerators. Stiff et al. (1983) have demonstrated that the addition of 6% hydroxyethyl starch (HES) reduced the “original” concentration of Me2SO (10%) by half. A serious problem regarding frozen peripheral HPC is the danger of clotting after thawing. Although it is highly advisable to use as little anticoagulant - mostly ACD-A (acid-citrate-dextrose, formula A) or heparin – as possible during the apheresis procedure from the patient’s point of view, this may lead to problems during the following processing and after thawing. So if low anticoagulant concentrations have been used during the apheresis procedure, we recommend adding additional ACD-A to the final apheresis product. There are reports in the literature (e.g., Douay et al., 1982; Goldman et al., 1978) on Me2SO toxicity at room temperature. As a consequence of these and other reports, in clinical protocols diluted and precooled Me2SO solutions are usually added at 0 ° to 4 °C. In an investigation with highly pure Me2SO (pharmaceutical grade), however, no impairment (colony assay) within the first hour was found when 5% or 10% of Me2SO were added at either 4 ° or 37 °C (Rowley and Anderson, 1993). Cool-down kinetics depend on several parameters: geometry (“undefined,” cylindrical, or plate shaped), sample thickness, composition (type and concentration of cryoprotectants), and thermal properties (heat capacity, heat conductivity) of the freezing bag and (if used) the surrounding metal envelope. Therefore, temperature time-histories measured in small reference samples (e.g., tubes) may differ significantly from those measured in the corresponding product bags. With regard to cryoprotectant concentration and cooling rates, we did not find significant differences in cell recovery and clonogenicity (Sputtek et al., 1997), provided at least 5% Me2SO was present and cooling rates did not exceed 5 °C/min. Our most recent data support the conclusion that a reliable –50 °C freezer is as suitable for long-term storage of HPC as is storage in the vapor phase over LN2. There was no systematic decline in viability measured in terms of 6 different parameters after more than 16 months storage in a –150 °C freezer (Sputtek et al. 2011). In our hands cell counts dropped significantly within 5 h after thawing compared to a high recovery when post thaw storage was performed at 20 °C and 0 °C, respectively. Therefore, we recommend to continue the common practice of thawing the frozen HPC units at the patient’s bedside. (Conflict of interest: The study on storage temperatures was supported by Ewald Innovationstechnik GmbH, Bad Nenndorf, Germany. Source of Funding: None.)
