High-Dimensional Single-Cell Mass Cytometry Demonstrates Differential Platelet Functional Phenotypes in Infants With...

Area of Science:

• Hematology
• Pediatric Cardiology
• Immunology

Background:

• Congenital heart disease (CHD) is linked to hematologic issues, including bleeding and clotting risks.
• Previous studies show conflicting results on platelet activation in CHD patients.
• Understanding platelet behavior in infants with CHD is crucial for managing complications.

Purpose of the Study:

• To develop a mass spectrometry method for characterizing single platelets in infants with CHD.
• To identify the reasons behind conflicting findings on platelet activation in CHD.
• To analyze platelet subpopulations and their functional characteristics in infants with CHD.

Main Methods:

• Enrolled 19 infants with CHD and 21 controls.
• Utilized single-cell mass cytometry to analyze platelet surface markers in whole blood.
• Performed plasma cytokine analysis for 52 vascular and inflammatory markers.

Main Results:

• Infants with CHD displayed significant differences in platelet activation and functional markers compared to controls.
• Identified 8 platelet subpopulations, with P1, P4, and P5 being more abundant in CHD infants and showing reduced aggregation but altered secretion.
• Observed increased hypogranular platelets and elevated plasma cytokines (e.g., IL-6, IL-8, VWF) in CHD infants.

Conclusions:

• Developed a mass cytometry approach to reveal platelet phenotypic heterogeneity in infants with CHD.
• Found distinct platelet subpopulations with reduced aggregation and secretory dysfunction in infants with CHD.
• Hypothesize that platelets in infants with CHD may be exhausted due to chronic stimulation, explaining vascular complications.