The function and structure of granulocytes collected using the IBM 2997 separator.

Area of Science:

• Hematology
• Transfusion Medicine
• Pharmacology

Background:

• Granulocyte collection via apheresis is crucial for treating conditions like neutropenia.
• Optimizing granulocyte yields is essential for effective patient outcomes.
• The use of sedimenting agents and pre-medications requires evaluation for efficacy and safety.

Purpose of the Study:

• To investigate the impact of oral methylprednisolone and hydroxyethyl starch on granulocyte recovery, morphology, and function.
• To determine if methylprednisolone enhances granulocyte yields during apheresis.
• To assess the safety and functional integrity of granulocytes collected under these conditions.

Main Methods:

• A volunteer donor program utilizing the IBM 2997 apheresis system.
• Processing of 10 liters of whole blood with an average procedure time of 2.4 hours.
• Comparison of granulocyte yields, morphology, and function in donors with and without methylprednisolone pre-medication, in the presence of hydroxyethyl starch.

Main Results:

• Donors receiving oral methylprednisolone showed significantly higher mean granulocyte yields (2.0 X 10(10)) compared to controls (1 X 10(10)) (P < 0.05).
• No significant differences were observed in packed cell volume or platelet contamination between groups.
• Light microscopy, ultrastructural studies, and functional assays (migration, chemotaxis, phagocytosis, intracellular killing) revealed no detrimental effects of methylprednisolone or hydroxyethyl starch on granulocytes.

Conclusions:

• Donor premedication with methylprednisolone significantly enhances granulocyte yields during apheresis when hydroxyethyl starch is used as a sedimenting agent.
• Neither methylprednisolone nor hydroxyethyl starch demonstrated any observable negative impact on granulocyte morphology or function.
• This combination represents a safe and effective strategy for improving granulocyte collection efficiency.