Norbert Ahrens

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Articles (9)

Background More granulocyte concentrates (GCs) could be produced for more patients from the same donor if apheresis bags were split and stored for longer periods of time. Hence, we tested the hypothesis that splitting and extension of storage of GCs do not impair granulocyte function or viability. Study Design and Methods Granulocyte apheresis concentrates were produced using modified fluid gelatin as a separation enhancer, split into two portions, and stored for 24 and 48 h. Granulocyte function, represented by cell migration, reactive oxygen species (ROS) production, and neutrophil extracellular trap formation (NETosis), was measured by live‐cell imaging. ROS production, adhesive surface protein expression, and viability were measured by flow cytometry. Results Splitting had no effect on any of the tested parameters. After 24 h of storage, live‐cell imaging showed no significant difference in migration, time to maximum ROS production, time to half‐maximum NETosis, viability, or CD11b expression, but ROS production induced by phorbol 12‐myristate 13‐acetate (PMA) decreased from an initial median fluorescence intensity of 1775–590 artificial units. After 48 h, PMA‐induced ROS production, viability, and migration declined, as reflected by decreases in median total distance (119 vs. 63.5 μm) and median Euclidean distance (30.75 vs. 14.3 μm). Conclusion Splitting GC products has no effect on granulocyte viability or function, but extended storage >24 h does compromise granulocyte function. The findings confirm that GCs should be transfused within 24 h of collection. Longer storage cannot be recommended.

Year:

2022

Background and Aims Platelets are prone to activation from handling; they are therefore transported as gently as possible, most commonly by courier. Speedier methods like pneumatic tube system (PTS) transport could improve patient care but may subject platelets to mechanical stress. To test the impact of mechanical stress caused by transport, we compared a PTS with a conveyor box and courier transport on apheresis platelet function. Methods Fourteen apheresis platelet concentrate triple donations were analyzed by light transmission aggregometry (LTA), rotational thrombelastometry (ROTEM), and flow cytometry before and after indoor transport over 800 m by PTS, conveyor, and courier, respectively, while recording shocks and vibrations with a high‐frequency acceleration data logger. Shock index scores were calculated as shock intensity (g‐force) times frequency. Results The shock index was 81 for courier, 6279 for conveyor, and 9075 for PTS. Flow cytometry revealed no significant difference in platelet surface expression of CD62p before (16%) and after transport via courier (15%), conveyor (14%), or PTS (16%). LTA with adenosine phosphate and thrombin receptor‐activating peptide‐6 resulted in comparable platelet aggregation for courier, conveyor, and PTS. ROTEM assays showed no relevant differences in coagulation time, clot formation time, and maximum clot firmness between transport modes. Conclusion Though the mechanical challenge was smallest with courier transport, there were no significant differences in platelet activation or aggregation between the three transport modes. These data contradict restrictions on the use of PTSs for platelet concentrate transport.

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2022

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2022

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2022

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2021

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2021

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2021

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2020

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2020

Collaborators (3)

James Hutchinson

Professor of Transplant Immunology

University Hospital Regensburg

GERMANY
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Michael Gruber

Head of the Lab

University Hospital Regensburg

GERMANY
View details

Viola Hähnel

-

GERMANY
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