Evaluating stored platelet shape change using imaging flow cytometry.

What is the context? Platelets for transfusion are currently stored for 5­7 days at room temperature, increasing the risk for bacterial growthCold storage reduces the risk for bacterial growth but reduces circulation timeStored platelet quality can be assessed by the light microscopy-based Morphology Score, first described in the 1970sDownsides of the Morphology Score include subjectivity, extensive training, and reduced availability in platelet laboratories.What is new? In this study, we provide data showing that the Morphology score is reduced to a binary spheres versus discs response in cold-exposed plateletsWe developed an imaging flow cytometry-based approach to quantify platelets' response to cold based on the two-dimensional projection of the three-dimensional shapes, i.e., fusiform (discoid) versus circular (discoid and spherical)We provide validation of this approach in mouse and human plateletsWhat is the impact?This study provides an easy and unbiased tool for laboratories working on circumventing the cold-induced storage lesion or documenting spherical shape change in general.