Liquid preservation of human neutrophils stored in synthetic media at 22
degrees C: controlled observations on storage variables
L Glasser, RL Fiederlein and DW Huestis
The purpose of this study was to use a chemically defined medium to
identify essential substances and optimal conditions for the liquid storage
of neutrophils at 22 degrees C. Several commercially available synthetic
media were evaluated: L-15, McCoy's 5a, M199, minimum essential medium,
Dulbecco's MEM, NCTC135, and RPMI 1640. Proteins, glucose, pH, and
neutrophil concentration were systematically studied. Neutrophils were
harvested by centrifugal cell separators or phlebotomy, and their
maintenance was evaluated by monitoring cell counts, dye exclusion,
phagocytosis, bacterial killing, and chemotaxis. Neutrophils stored equally
well in all synthetic media except L-15; however, chemotaxis was poorly
maintained in synthetic media as compared with autologous plasma. RPMI 1640
was arbitrarily selected as a basal medium to evaluate storage variables.
RPMI 1640 supplemented with albumin to a concentration of 1% improved
chemotaxis and was equivalent to plasma as a storage medium with regard to
the in vitro functions tested. Cohn fractions IV-1, IV-4, and gamma
globulin were not effective substitutes for albumin. Glucose is essential
for neutrophil storage; its absence from the medium correlated with poor
cell function. Optimal glucose requirements depend on the cell
concentration. High glucose concentrations were toxic to neutrophils; at
1,000 mg/dL, chemotaxis was depressed by 58%. Glucose utilization was
dependent on the initial pH of the medium and on the cell concentration. A
wide range of hydrogen ion concentrations was tolerated, and the optimum pH
range was 7.2 to 7.8. Cell concentration is an important variable because
it affects the pH of the medium as well as glucose utilization.
Volume 66,
Issue 2,
pp. 267-272,
08/01/1985
Copyright © 1985 by The American Society of Hematology
