Evaluation of solutions for the storage of granulocyte colony-stimulating factor-mobilized granulocyte concentrates

Background High cell counts in granulocyte colony-stimulating factor (G-CSF )mobilized granulocytes are detrimental to concentrate storage. An eightfol d dilution with autologous plasma improves storage, but this method is impr actical, The purpose of this study was to identify an infusible solution th at could be used in place of autologous plasma to dilute and store granuloc ytes. Materials and Methods Granulocytes collected from donors given dexamethason e (8 mg per os) and/or G-CSF (5 mug/kg subcutaneously [SQ]) were diluted ei ghtfold in the following cell culture media: X-Vivo 10, Dulbecco's modified Eagle's minimal essential medium (DMEM) or Iscoves modified Dulbecco's med ium (IMDM); or in the following infusible solutions: Plasma-Lyre A; Normoso l R; lactated ringers, supplemented with 1% human serum albumin and 50 mM h istidine (LRAH); or Plasma-Lyre A supplemented with 50 mM histidine buffer or 25 mu HEPES buffer plus 1% human serum albumin. The granulocytes were st ored for 48 h at room temperature. White blood cell (WBC) counts, WBC viabi lity and pH were measured after approximate to 2 h, 24 h and 48 h of storag e. Results Cell counts, viability and pH were maintained after 2 h, 24 h and 4 8 h in cells stored in the three cell culture media. The pH fell slightly a fter 48 h to 68.6 +/- 0.10 in granulocyte concentrates diluted in LRAH, but fell to a greater extent after 24 h and 48 h, to 6.36 +/- 0.23 (48-h value ) in granulocyte concentrates diluted in Plasma-Lyre A and to 6.40 +/- 0.19 (48-h value) in granulocyte concentrates diluted in Normosol R. The cell c ounts of concentrates diluted in LRAH were stable for 48 h, but fell in gra nulocyte concentrates stored in Plasma-Lyre A and Normosol R. Plasma-Lyre A supplemented with histidine maintained the pH of diluted granulocyte conce ntrates better than Plasma-Lyre A supplemented with HEPES; 6.91 +/- 0.10 an d 6.65 +/- 0.11, respectively, after 24 h. Cell counts were maintained best in granulocyte concentrates diluted in Plasma-Lyre A supplemented with alb umin and one or both of the buffers. Conclusions Culture media were best for granulocyte storage, but they are n ot approved for in vivo use. Infusible solutions are not buffered adequatel y and lack sufficient protein, but infusible solutions, such as lactated Ri nger's solution or Plasma-Lyte A supplemented with buffers and albumin, hol d promise as effective and licensable solutions for granulocyte storage.