Gary Moroff

Cell loss and recovery in umbilical cord blood processing: a comparison of postthaw and postwash samples

BACKGROUND: Engraftment after umbilical cord blood (UCB) transplantation is highly dependent on nucleated cell (NC) and CD34+ cell content. Current standard postthaw (PT) processing includes a wash step to remove dimethyl sulfoxide (DMSO), lysed red cells, and stroma. The contribution of the wash step to cell loss and ultimately the dose of cells available for transplant have yet to be systematically reported. This study examines the effect of the wash step as well as that of PT storage on various quality control variables of UCB units.

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.

Retention of cellular properties of PBPCs following liquid storage and cryopreservation

BACKGROUND: G–CSF‐mobilized PBPCs are routinely cryopreserved within 24 hours of collection. The ability to hold PBPCs for extended time would offer increased flexibility for patients and hospitals. Retention of PBPC properties following overnight shipping, extended liquid storage at 1 to 6°C, and cryopreservation was evaluated.

Multiple-laboratory comparison of in vitro assays utilized to characterize hematopoietic cells in cord blood.

BACKGROUND:  Understanding the variability in results obtained by multiple laboratories is important because cord blood units are distributed worldwide for transplantation.

The influence of simulated shipping conditions (24- or 30-hr interruption of agitation) on the in vitro properties of apheresis platelets during 7-day storage.

BACKGROUND: Platelet (PLT) components undergo interruption of agitation during shipment. Studies have demonstrated maintenance of PLT quality of whole blood–derived PLT concentrates during a 24‐hour interruption of agitation, but data are not available for apheresis PLTs in 100 percent plasma.

Storage of pools of six and eight platelet concentrates

Platelet concentrates (PCs) prepared from units of whole blood are routinely stored singly at 20 to 24 degrees C and pooled prior to transfusion. Studies have been conducted to evaluate the in vitro properties of pools of six (n = 19) and eight (n = 17) ABO‐identical PCs after storage, with comparative studies involving single units (n = 33). The pools were prepared using the sterile connecting device. One‐ day‐old and 3‐day‐old PCs were pooled and stored for a total of 5 days in a container system consisting of two 1000‐mL polyolefin containers. The pooled platelet suspension was divided approximately equally between the two containers. The platelet count was reduced by less than 5 percent during storage of the pools, which is similar to the reduction found with storage of control units of single PCs. The volume loss due to pooling was 9.6 +/− 1.9 percent (mean +/− 1 SD). The pH of the PC pools was approximately 7.0 after 5 days of storage, with no pool having a pH below 6.2. In vitro platelet properties, such as morphology score, extent of shape change induced by ADP, total ATP, aggregation response to ADP and collagen, response to hypotonic stress, lactate dehydrogenase discharge, and beta‐thromboglobulin release, were similar for pools and control single PCs. In addition, comparable low levels of thymidine uptake were detected in the mononuclear leukocyte fraction of pooled and unpooled PCs that were stored for 5 days at 20 to 24 degrees C, which indicates that the mixing of lymphocytes in the pool did not stimulate in vitro immunologic reactions. Culturing of samples at the conclusion of storage did not show evidence of bacterial contamination. These studies demonstrate that pools of ABO‐identical PCs have satisfactory in vitro platelet properties after storage.

Extended storage of AS-1 and AS-3 leukoreduced red blood cells for 15 days after deglycerolization and resuspension in AS-3 using an automated closed system.

BACKGROUND:  The utilization of cryopreserved red blood cell (RBC) units had been limited by a maximum postdeglycerolization storage of 24 hours at 1 to 6°C until the recent development of a closed system for the glycerolization and deglycerolization process.

Assessment of cord blood hematopoietic cell parameters before and after cryopreservation.

BACKGROUND: The testing of cord blood (CB) progenitor and stem cell units for transplantation suitability involves enumeration of total nucleated cells before freezing. CD34+ cell counts may also be a means of determining suitability. Studies have been conducted to evaluate how specific storage conditions influence cell counts.

Effect of an 8-hour holding period on in vivo and in vitro properties of red cells and factor VIII content of plasma after collection in a red cell additive system.

Extension of the holding time for whole blood units from 6 to 8 hours at ambient temperature should provide enhanced flexibility in the preparation of platelet concentrates (PCs). A paired study was conducted to evaluate the characteristics of stored red cells (RBCs) and plasma prepared from whole blood collected into a red cell additive system (CPD‐ADSOL) after an extended holding time. An individual donated a unit of whole blood on two occasions; 1 unit was held for 6 hours before processing and the other for 8 hours. Autologous RBC 24‐ hour survival levels after 42 days of storage were comparable. Laboratory A, using a 99mTc‐51Cr technique, found mean survival levels of 79 percent (6‐hour hold) and 78 percent (8‐hour hold) (n = 8). Analysis by the single‐label procedure found the mean levels to be 82 and 81 percent. Laboratory B, using an albumin 125I‐51Cr technique, found mean survival levels of 74 and 72 percent (n = 10). Mean hemolysis and ATP levels were found to be comparable after 42 days of storage following 6‐ and 8‐hour holding periods. 2,3 DPG levels were reduced to a greater degree during the longer hold. The factor VIII levels in plasma frozen for at least a month after 6‐ and 8‐hour holding periods were comparable; thawed plasma contained mean levels of 0.77 and 0.76 units per mL (n = 21). These studies indicate that components prepared by using a CPD‐ADSOL system after holding periods of 6 and 8 hours have comparable properties.

The risk of posterior subcapsular cataracts in granulocyte donors.

BACKGROUND: Therapeutic use of adrenal corticosteroids is a risk factor for the development of posterior subcapsular cataract (PSC). Because corticosteroids are given to donors of apheresis granulocytes (PMNs) to improve yield, this study was performed to determine the prevalence of PSCs in PMN donors relative to a matched control group of apheresis platelet (PLT) donors.