# A platelet transcriptomic signature of thromboinflammation predicts cardiovascular risk

## TL;DR

This study identifies a platelet RNA signature that predicts cardiovascular risk by capturing thromboinflammatory activity linked to immune signaling.

## Contribution

The study introduces TIPS, a novel 42-gene platelet RNA signature for cardiovascular risk stratification and therapeutic targeting.

## Key findings

- MPAhi individuals showed increased platelet activation markers and immune signaling pathways.
- TIPS correlated with MPA levels and predicted future cardiovascular events in revascularization patients.
- TIPS was elevated in patients with COVID-19 and myocardial infarction and was modifiable by ticagrelor.

## Abstract

Platelets are increasingly recognized as active participants in immune signaling and systemic inflammation. Upon activation, platelets form monocyte platelet aggregates (MPA) representing the crossroads of thrombosis and inflammation. We hypothesized that platelet transcriptomics could capture this thromboinflammatory axis and identify individuals at elevated cardiovascular risk.

Platelets were isolated and sequenced. Individuals were categorized as MPAhi or MPAlo based on consistently high or low MPA levels across time points.

Among 149 participants (median age 52 years, 57% female, 50% non-White), MPAhi individuals exhibited increased expression of platelet activation markers P-selectin (P < 0.001), PAC-1 (P = 0.021), and CD40L (P < 0.001) and enriched immune signaling pathways. Informed by MPA levels and derived from the platelet transcriptome, we developed a 42-gene thromboinflammation platelet signature (TIPS), which correlated with MPA levels in multiple cohorts and was reproducible over time. TIPS was elevated in patients with COVID-19 (P = 0.0002) and myocardial infarction (Padj = 0.008), and as in predicted future cardiovascular events in patients who underwent lower extremity revascularization after a median follow-up of 18 months (adjusted for age, sex, race, and ethnicity [adjHR] 1.55, P = 0.006). Notably, TIPS was modifiable by ticagrelor (P = 0.002) but not aspirin.

These findings establish MPA as a biomarker of thromboinflammation and introduce TIPS, a platelet RNA signature, that captures thromboinflammation and provides a promising tool for cardiovascular risk stratification and a potential therapeutic target.

NCT04369664

NIH R35HL144993, NIH R01HL139909, and AHA 16SFRN2873002 to JSB, DFG Walter-Benjamin-Programme 537070747 to AB.

Monocyte platelet aggregates are a biomarker of thromboinflammation. We created and validated a platelet RNA signature, that captures platelet-immune activity and associates with cardiovascular risk.