High Autophagy Patterns in Swelling Platelets During Apheresis Platelet Storage

Area of Science:

• Blood banking and transfusion medicine
• Cellular biology
• Biochemistry

Background:

• Platelets exhibit significant morphological and functional changes during storage.
• The relationship between platelet structural heterogeneity and autophagy remains poorly understood.

Purpose of the Study:

• To investigate platelet autophagy in vitro during routine storage.
• To explore the role of reactive oxygen species (ROS) in regulating platelet autophagy.

Main Methods:

• Flow cytometry to assess ROS and autophagy levels.
• Western blot to measure autophagy-associated proteins (LC3I, LC3II, Beclin1, Parkin, PINK1).
• Transmission electron microscopy (TEM) for morphological analysis.

Main Results:

• Stored platelets showed increased total and mitochondrial ROS.
• Autophagy marker LC3 was amplified, correlating with increased mitochondrial ROS.
• Large, swollen platelets displayed higher LC3 levels and enhanced autophagy.
• Beclin1 and LC3 II/LC3 I ratio increased, while Parkin and PINK1 levels remained stable.

Conclusions:

• Platelet autophagy is associated with increased mitochondrial ROS during storage.
• A subpopulation of large, swollen platelets exhibits distinct autophagy patterns.
• These findings suggest swelling platelets have a higher autophagy rate during storage.