Abstract Number: PB0970
Meeting: ISTH 2021 Congress
Theme: Platelets and Megakaryocytes » Platelet Function and Interactions
Background: Platelets within one individual display heterogeneity in reactivity, size, age, and expression of surface receptors. We and others have shown that larger platelets show increased responsiveness to activating stimuli compared to smaller platelets. Next to that, it is considered that the RNA content in juvenile platelets is associated with higher reactivity.
Aims: To investigate the combined intra-individual contribution of platelet size, platelet age, and receptor expression levels on the reactivity of platelets.
Methods: Fractions of large and small platelets from healthy donors were separated by differential centrifugation. Multicolour flow cytometry with subsequent automated high-dimensional clustering analysis (FlowSOM) was used to identify and phenotype platelet subpopulations formed in response to different doses of CRP-XL, TRAP6, and ADP. Platelet age correlations were assessed by co-staining of labelled oligo-dA/T with either anti-glycoprotein (GP)VI or anti-HLA-I antibodies. Whole blood reconstituted with size-separated platelet fractions were perfused over a collagen-coated surface to assess thrombus formation.
Results: Clustering analysis of the flow cytometric data showed that highly reactive platelet populations are characterised by highest GPVI and HLA-I (marker for juvenile platelets) expression (Figure 1A). Platelets with high expression of GPVI also show a higher RNA content (Figure 1B). Highly reactive juvenile platelets were found to be enriched in the large platelet fraction (Figure 1C). Even when adjusted to the same platelet mass, the larger platelet fraction resulted in faster adhesion to collagen under flow and the formation of larger thrombi, compared to the small platelet fraction.
Conclusions: High GPVI expression is a feature of highly reactive juvenile platelets, which are predominantly found among large platelets and likely promote thrombus formation.
Funded by Landsteiner Foundation for Blood Transfusion Research
To cite this abstract in AMA style:
Veninga A, Handtke S, Tullemans BME, Brouns SLN, Greinacher A, Heemskerk JWM, van der Meijden PEJ, Thiele T. Highly Reactive Juvenile Platelets Express Higher Levels of GPVI in a Size-related Manner [abstract]. Res Pract Thromb Haemost. 2021; 5 (Suppl 2). https://abstracts.isth.org/abstract/highly-reactive-juvenile-platelets-express-higher-levels-of-gpvi-in-a-size-related-manner/. Accessed March 21, 2024.« Back to ISTH 2021 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/highly-reactive-juvenile-platelets-express-higher-levels-of-gpvi-in-a-size-related-manner/