PB0122 - Circulating Immature Platelet Fraction is Associated with Increased Platelet Activity

Sunday, June 25, 2023

18:30 – 19:30 ET

Room: Exhibition

Presenting Author(s)

Ariel Schaap, MD

Fellow
New York University Grossman School of Medicine
New York, New York, United States

Co-Author(s)

EL

Elliot Luttrell-Williams

Associate Research Scientist
New York University Grossman School of Medicine
New York, New York, United States
YX

Yuhe Xia

MS
NYU Grossman School of Medicine
New York, New York, United States
AA

Adedoyin Akinlonu

Postdoctoral Fellow
New York University Grossman School of Medicine
New York, New York, United States
MF

Maja Fadzan

Clinical Research Coordinator
New York University Grossman School of Medicine
New York, New York, United States
MJ

Manila Jindal

Clinical Assistant Professor
New York University Grossman School of Medicine
New York, New York, United States
HI

Homam Ibrahim

Clinical Assistant Professor
New York University Grossman School of Medicine
New York, New York, United States
Tessa J. Barrett, PhD

PhD
NYU Grossman School of Medicine
New York, New York, United States
JB

Jeffrey S. Berger

Associate Professor of Medicine and Surgery
New York University Grossman School of Medicine
New York, New York, United States

Background: Immature (reticulated) platelets are newly released from the bone marrow. They are larger, and contain more RNA than mature platelets. Many techniques used to measure immature platelets via flow cytometry are costly, time consuming, and prone to laboratory-based variability. Recently, improved automated methods to measure circulating immature platelet fraction (IPF) have emerged.

Aims: To evaluate the association between IPF and other well-established markers of platelet activity.

Methods: One hundred and eleven participants (median age 53 years, 59.4% female) had platelet activity measures performed. IPF was determined using an automated hematology analyzer (Sysmex XN-1000, Sysmex America Inc, Lincolnshire, IL). IPF is expressed as a percentage of the total platelet population. Because it was not normally distributed, IPF was log transformed. Platelet surface expression of P-selectin, activated integrin αIIbβ3 (PAC-1), CD40 receptor, and CD40 ligand (CD40L) in the basal state and following thrombin (0.025 U/ml) stimulation were measured by flow cytometry. Pearson’s correlation coefficient was calculated for the relationship between IPF and platelet activity.

Results: After adjustment for age, sex, race, and ethnicity, circulating IPF was associated with markers of platelet activity in both the basal state and following stimulation with thrombin. Following multivariable adjustment, IPF was associated with P-selectin (p=0.055), CD40 (p=0.006), and CD40L (p=0.073). When stimulated with thrombin, platelet expression of P-selectin (p=0.003), PAC1 (p=0.003), CD40 (p=0.018), and CD40L (p=0.002) all significantly correlated with IPF.

Conclusion(s): Circulating IPF is associated with platelet expression of P-selectin, PAC1, CD40, and CD40L – all of which are markers of increased platelet activity. Our data suggest that IPF could be considered a readily accessible surrogate of platelet activation.