Background: The objective of this study was to establish a mobilization and apheresis regimen for collection of two consecutive polymorphonuclear neutrophil (PMN) concentrates from the same donor.
Study design and methods: In this prospective study, 111 healthy unrelated volunteers underwent either one (Group 1, n = 57) or two consecutive granulocyte apheresis procedure (Group 2, n = 54) using the a cell separator (Spectra). Both Group 1 and 2 donors were initially mobilized with glycosylated G-CSF 6.0 micro g per kg (range, 5.2-7.0 micro g/kg) subcutaneously plus oral dexa-methasone (DXM, 8 mg) and underwent granulocyte apheresis (GA-1) 16 hours (range, 13-18 hr) after initial G-CSF+DXM. Group 2 donors were remobilized with a second DXM dose of 8 mg (n = 13), 4 mg (n = 15), 1.5 mg (n = 13), or none (n = 13), and a second apheresis (GA-2) was run 40 hours (range, 37-42 hr) after G-CSF+DXM administration and 12 hours after remobilization with DXM alone.
Results: Based on equivalent median preapheresis WBC and PMN counts of around 35 x 10(9) WBCs per L and 33 x 10(9) PMNs per L after initial mobilization the GA-1 yields were 85 x 10(9) PMNs per U (range, 34-150) in Group 1 and 75 x 10(9) PMNs per U (range, 35-135) in Group 2 (p = 0.14, NS). In Group 2, median preapheresis values of 19.6 x 10(9) WBCs per L (range, 9.5-37.0) and 16.6 x 10(9) PMNs per L (range, 8.8-34.8) were measured after remobilization and GA-2 yields of 49 x 10(9) WBCs per U (range, 26-113) and 42 x 10(9) PMNs per U (range, 21-95) were obtained. Borderline statistical differences in the GA-2 yields were observed from the remobilized donors: 8 mg: 36 x 10(9) PMNs per U (range, 23-60); 4 mg: 47 x 10(9) PMNs per U (range, 21-56) (p </= 0.04); 1.5 mg: 45 x 10(9) PMNs per U (range, 23-79); placebo: 36 x 10(9) PMNs per U (range, 26-95) (p </= 0.04).
Conclusion: Two consecutive neutrophil concentrates for transfusion can be obtained after single stimulation with Lenograstim+DXM. A second application of DXM alone is necessary, but of limited value.