Liquid preservation of highly purified human granulocytes

Effects of storage and incubation conditions on human granulocyte phagocytic, bactericidal, and chemotactic functions

This study was undertaken to determine the effects of different incubation conditions on human granulocyte (PMN) bactericidal, phagocytic, and chemotactic functions. Specifically, (1) how long may a patient's blood be held before assay and maintain original PMN function, and (2) how long may isolated PMNs be incubated for the purpose of exposure to various agents and still maintain original function? PMNs isolated following storage of whole heparinized blood at 4 degrees C for 24 and 48 hr phagocytized as well as fresh cells and their bactericidal activity was 96 and 85% of control values after 24 and 48 hr, respectively. Chemotaxis decreased to 62% of control after 24 hr. The bactericidal capacity of isolated PMNs stored at 4 degrees C for 24, 48, and 72 hr decreased to 85, 81, and 78% of controls, respectively. Phagocytosis after 24 hr storage was equal to controls. Chemotaxis was decreased to 59 and 34% of controls after 24 and 48 hr, respectively. Isolated PMNs incubated at 37 degrees C demonstrated impairment in phagocytic capacity after only 4 hr.

Changes in neutrophil aggregation and chemotaxis response during 18-hour cold storage

Providing neutrophil transfusions to septic neonatal patients with depleted neutrophil reserves can be troublesome and require unscheduled blood donations. Buffy coats from stored whole blood are a potential source of neutrophils provided they remain viable during the interval between the whole blood collection and the buffy coat production. This study determined neutrophil function during storage of whole blood at 4 degrees C for 18 hours. Whole blood pH, hematocrit, platelet, and white cell counts remained unchanged. Chemotactic response to formyl methionyl leucyl penylalanine (FMLP) declined from 172.5 +/- 29 units (mean +/- SD) to 125 +/- 48 at 9 hours and 63.6 +/- 48 (p less than 0.05) at 18 hours. Aggregation response to FMLP remained normal for 9 hours but dropped to 15.5 percent of normal after 18 hours. Neutrophil response to cytaxins was maintained for at least 9 hours during storage of whole blood at 4 degrees C but seriously declined within 18 hours. Limiting 4 degrees C storage of whole blood to 9 hours prior to preparing buffy coats may provide flexibility needed for urgent provision of neutrophil transfusions.

Neutrophil migration in canines: in vivo comparison of granulocyte function following 24-hour storage at 6 or 20 degrees C of leukocyte concentrates or of granulocytes purified by counterflow centrifugation--elutriation

The use of granulocyte-rich concentrates from leukaphresis purified by counterflow centrifugation--elutriation to obtain pure granulocytes for transfusion studies in cyclophosphamide-induced neutropenic animal models is reported. Our data for granulocyte-rich leukapheresis concentrates indicate that room temperature (20 degrees C) appears to be preferred to 6 degrees C for short-term granulocyte storage. The data also indicate that although the granulocytes isolated by counterflow centrifugation--elutration may retain in vitro functions of chemotaxis, phagocytosis, and bactericidal activity, the in vivo function of migration into skin chambers for isolated granulocytes is seriously impaired after storage for 18 to 24 hr at both 6 and 20 degrees C. This loss of in vivo function of stored granulocytes occurs in isolated granulocytes obtained by both counterflow centrifugation--elutriation and dextran sedimentation, and it is not observed in the leukocyte concentrates held at 20 degrees C. The results of these studies are four-fold. First, freshly isolated granulocytes display no apparent loss of either in vivo or in vitro function. Second, granulocytes isolated by counterflow centrifugation--elutriation or dextran sedimentation and stored at 6 or 20 degrees C are severely impaired in terms of their in vivo chemotactic function but display no loss of in vitro efficacy. Third, 20 degrees C storage of granulocyte-rich leukapheresis concentrates for 18 to 24 hr is superior to 6 degrees C storage. Fourth, in vitro analysis may be limited in its ability to indicate in vivo function as a measure of success in granulocyte preservation studies.