Whole Blood Analysis of Leukocyte‐Platelet Aggregates

Abstract

In inflammatory and thrombotic syndromes, platelets aggregate with circulating leukocytes, especially monocytes and neutrophils. The platelet binding is initiated primarily through platelet surface expression of P‐selectin (CD62P) following activation‐dependent degranulation. The levels of P‐selectin involved can be low enough to make direct measurement difficult, but detection of leukocyte‐platelet aggregates is relatively simply by whole‐blood flow cytometry. Light scatter and at least one leukocyte‐specific antibody are used to gate the desired population, and the presence of associated platelets is detected by immunostaining for abundant platelet‐specific markers.

Platelets induce neutrophil extracellular traps in transfusion-related acute lung injury

“…It is known, however, that approximately 10%-20% of neutrophils circulate as neutrophil-platelet aggregates (ref. 22 and data not shown). Therefore, NET formation induced by TRAP alone may be explained by preexisting neutrophil-platelet aggregates present in the neutrophil preparation.…”

Circulating Platelet-Neutrophil Aggregates Play a Significant Role in Kawasaki Disease

“…Approximately 10-20% of neutrophils circulate as platelet-neutrophil aggregates. 31 Platelet-neutrophil aggregates can be mediated via P-selectin aggregates in patients with KD complicated with CAA have a greater potential for activation than those in patients without CAA and may contribute to thrombosis and prolonged inflammation, increasing the severity of coronary outcomes. In contrast, no significant differences in the rates of platelet-neutrophil aggregates were seen between the IVIG responders and nonresponders before IVIG treatment.…”

Design, formulation and sensory evaluation of a polyphenol-rich food placebo: an example of aronia juice for food intervention studies

“…The platelet activation markers (P-selectin and GPIIbIIIa) and platelet-leukocyte aggregates were measured by whole-blood flow cytometry according to a previously published protocol (Michelson et al 2000;Krueger et al 2002;Barnard et al 2003). For the determination of platelet activation, aliquots of whole blood dissolved (1:10) in Hepes-Tyrode Buffer (HTB) were incubated with peridinin chlorophyll protein (PerCP)-conjugated anti-CD61, phycoerythrine (PE)-conjugated CD62P (anti-P-selectin) and fluorescein isothiocyanate (FITC)-conjugated PAC1 (antiGPIIb-IIIa) monoclonal antibodies with or without a suboptimal concentration of platelet agonists (0.5 lM adenosine diphosphate, ADP) for 20 min in the dark, at room temperature.…”