In vitro granulocyte function as affected by filter loading time and tapping during filtration leukapheresis

Area of Science:

• Hematology
• Immunology
• Cellular Biology

Background:

• Polymorphonuclear cells (PMNs) are crucial for immune response.
• Filtration leukapheresis (FL) is a method for collecting PMNs.
• The impact of collection methods on PMN function requires further investigation.

Purpose of the Study:

• To evaluate the effect of manual tapping (MT) during FL on PMN function.
• To determine if filter loading time (FLT) influences PMN function after collection.

Main Methods:

• Harvesting PMNs from 16 healthy subjects using FL with varying FLTs (30 min to 4 h).
• Assessing PMN function in vitro using chemotaxis, phagocytosis, and bactericidal assays.
• Comparing PMNs collected with and without MT.

Main Results:

• Manual tapping during PMN elution significantly compromised PMN function in vitro.
• Compromised function was observed regardless of the filter loading time.
• PMNs collected without MT exhibited near-normal function compared to controls.

Conclusions:

• Manual tapping during filtration leukapheresis negatively impacts PMN function.
• Collecting PMNs without manual tapping preserves their functional integrity.
• Optimizing leukapheresis techniques is essential for obtaining functional immune cells.