A Feasibility Study for Cryopreserving Peripheral Blood Stem Cell Collects at High Cell Concentration / 대한수혈학회지

BACKGROUND: For autologous hematopoietic stem cell transplantation (HSCT), the volume of infused and DMSO contained in graft are the major causes of complications related to infusion. In this study, we evaluated feasibility of cryopreserving peripheral blood stem cell collects (PBSCC) at high cell concentration. METHODS: PBSCC from 40 patients with multiple myeloma or lymphoma were split and cryopreserved at two different concentrations of TNCs; one for standard concentration (SC) (2x108 cells/mL) and the other for high concentration (HC) (3x108 cells/mL). The viability of total nucleated cells and CD34+ cell count were examined before cryopreservation and after thawing. CFU-GM was examined with thawed products. Data were analyzed as two groups between good mobilizer (GM) and poor mobilizer (PM). RESULTS: There were no differences in TNC viability between SC and HC of all patients (P=0.0656) and PM (P=0.9658), however HC of GM showed significantly lower viability than SC (P=0.0314). CD34+ cell viability did not differ between SC and HC. CD34+ cell recovery was decreased in HC of all patients (P=0.459) and GM (P=0.0164), but no differences between SC and HC in PM (P=0.9658). CFU-GM clonogenic efficiency between SC and HC was not different in all patients (P=0.0635) and PM (P=0.8984), but was decreased in HC of GM (P=0.0427). CONCLUSION: Cryopreservation of PBSCC at 3x108 cells/mL seems to have minimal adverse effect on the quality of PBSC after thawing, particularly in PM. This approach may help to reduce infusion related complications while decreasing the cost of processing and storage of PBSCC.

The Influence of Plateletpheresis Donors' Attitudes on Their Willingness to Give Future Donations and to Recommend Donation to Others / 대한수혈학회지

BACKGROUND: In order to facilitate public participation in platelet donation, it is important to encourage current donors to give future donations and to recommend others to donate. The aim of this study was to examine the influence of the attitudes of plateletpheresis donors' toward their willingness to give further donations and to recommend others to donate. Understanding the factors influencing the donors' behavioral patterns toward donation would help determine a plan for how to increase the recruitment of donors and manage platelet resources effectively. METHODS: A questionnaire-based survey was carried out on a total of 198 plateletpheresis donors recruited from university hospitals and blood centers of the Korea National Red Cross. The questionnaire contained 29 items, which consisted of 10 items related to the perception of donation, 7 items to their level of satisfaction in donating, 2 items related to their willingness to give future donations and recommend others to donate, 6 items on how to improve the quality of donation services, and 4 items related to the donor's general characteristics. Multiple-regression analysis was used to analyze the data. RESULTS: The plateletpheresis donors with higher perception and satisfaction scores were found to be more willing to give future donations and to recommend others to donate. The number of voluntary donors was higher than that of non-voluntary donors both in the university hospital and in blood centers. The scores of perception and satisfaction, along with the willingness to make future donations, were much higher in the blood centers than in the hospitals. The misperception about blood donation was found to be the major cause of the low donation rate. CONCLUSION: Since the behavioral patterns of plateletpheresis donors are influenced by their attitudes toward donation, more efforts and administrative supports will be needed to improve the quality of plateletpheresis services and the public perception of donation.

Therapeutic Plasma Exchanges in Patients with Thrombotic Thrombocytopenic Purpura/Hemolytic Uremic Syndrome / 대한임상병리학회지

BACKGROUND: Thrombotic thrombocytopenic purpura/hemolytic uremic syndrome (TTP/HUS) is a disease entity defined by the presence of thrombocytopenia and microangiopathic hemolytic anemia with or without fever, neurologic and renal symptoms. Therapeutic plasma exchange (TPE) has proven to be an effective treatment for TTP/HUS and has decreased mortality. We evaluated the effectiveness of TPE for TTP/HUS at the Department of Clinical Pathology, Samsung Medical Center during the last 6 years. METHODS: We assessed retrospectively the chief complaints, the clinical course, the treatment and the outcome in 17 TTP/HUS patients treated with TPE from December 1994 to May 2001. Minimal diagnostic criteria for TTP/HUS were unexplained thrombocytopenia and microangiopathic hemolytic anemia, with or without fever, neurologic, and renal symptoms. The range of ages of the patients was 15 to 63 years and the female to male ratio was 2:1. RESULTS: The most frequent clinical presentation was a renal problem (71%), followed by fever (53%) and neurologic symptoms (24%). The causes of TTP/HUS followed in the order of frequency: idiopathic (41%), suspicious for Escherichia coli O157: H7 infection (24%), systemic lupus erythematosus (18%), mitomycin C induced (12%), and preeclampsia (6%). A total of 229 TPE procedures were performed for 17 patients (mean: 13 procedures). The replacement fluids for TPE were fresh frozen plasma (59%) and cryosupernatant (41%). Thirteen patients (76%) survived and three of them relapsed (23%); however, they responded to further treatment. In comparing the laboratory results between pre and post TPE, significant changes were found in the white blood cells and platelet counts, creatinine, total bilirubin, and lactic dehydrogenase. The initial symptoms did not indicate a recurrence rate and a variety of drugs were used, except for corticosteroid administration. CONCLUSIONS: TTP/HUS patients responded well to TPE. The overall efficacy of TPE for TTP/HUS was 76%. The causes of TTP/HUS, the administered drugs and the replacement fluid did not affect the patient's prognosis.

Evaluation of COBE Spectra "Leukocyte Reduction System (LRSTM)" for the Production of Leukocyte-Reduced Platelets / 대한수혈학회지

BACKGROUND: Leukocytes have been shown to be an undesirable contaminants in platelet transfusions because these contaminants may develop various adverse consequences. Current platelet products by plateletpheresis are heavily contaminated with leukocytes. Recently, new platelet apheresis system (COBE Spectra LRSTM) was designed to make it possible to collect platelets with very low leukocytes contamination. We evaluated the COBE Spectra LRSTM by comparing it with COBE Spectra. METHODS: Plateletpheresis procedures were performed on 75 normal donors; 45 procedures for COBE Spectra LRSTM and 30 procedures for COBE Spectra. We evaluated platelet yields, processing times, efficiency, and leukocytes content on two apheresis machines. RESULTS: Comparative results of COBE Spectra LRSTM with COBE Spectra were as follows: the mean processing time per unit was 97 min and 91 min, the efficiency per unit was 38.4 +/- 11.5% and 46.9 +/- 12.1%, the mean leukocytes contamination per unit was 6.1x104 and 2.1x106 respectively (p0.05). CONCLUSIONS: Platelet collections with COBE Spectra LRSTM demonstrated comparable platelet yields and strikingly low WBC contamination. This study indicate that the COBE Spectra LRSTM is an efficient and reliable system for the collection of platelets with very low residual WBC levels. It seems that leukocyte reduction filter for platelet products by COBE Spectra LRSTM is not necessary for further removal of leukocytes to prevent alloimmunization, non-hemolytic transfusion reactions, certain viral and bacterial infections.