A comparative study between light transmission aggregometry and flow cytometric platelet aggregation test for the identification of platelet function defects in patients with bleeding

Figures

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  Fig. 1. Flow cytometric platelet aggregation of a healthy control. Dot plots showing platelets in unstimulated (t=0 min) and ADP-stimulated state (t=10 min) in a healthy control (left and right, respectively). The platelets are gated on a log forward (FSC) and side scatter (SSC) (upper panel) and examined on CD31-FITC and CD31-PE combination (lower panel). The double-colored events (Q2) represent the platelet aggregates, Q1 represents the CD31-PE-labeled platelets, Q4 represents the CD31-FITC-labeled platelets, and Q3 represents the unstained events (plasma, debris, etc.). The % double-colored events in this control in unstimulated t=0 min and ADP-stimulated platelet mix at t=10 min are 1.8% and 41.4% respectively.

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  Fig. 2. Scatter diagrams showing the distribution of test results. The % maximum amplitude of response to ADP, collagen, and ristocetin in light transmission aggregometry (A) and the % double-colored events of ADP-, collagen-, and ristocetin-stimulated platelet mix on flow cytometric platelet aggregation assay of healthy controls and patients are shown (B).

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  Fig. 3. Scatter plots showing the test results of patients 1, 2, 3, and 4 with a GT-like pattern on light transmission aggregometry (LTA). (A) % aggregation of LTA and (B) % aggregation of flow cytometric platelet aggregation to agonists ADP, collagen, and ristocetin are plotted. Note that patient 1 in the Fig. 3A has superimposed ADP and collagen values.

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  Fig. 4. Flow cytometric platelet aggregation assay of a patient with Glanzmann thrombasthenia (GT). Dot plots showing platelets in unstimulated (t=0 min) and agonist-stimulated state (t=10 min) in a GT patient. The % double-colored events in this patient in unstimulated t=0 min and ADP-, collagen-, and ristocetin-stimulated platelet mix at t=10 min are 0.6% and 0.7%, and 14.3% and 29.9% respectively.