Journal Article

An Intense and Short-Lasting Burst of Neutrophil Activation Differentiates Early Acute Myocardial Infarction from Systemic Inflammatory Syndromes

Cianflone, Domenico, Slavich, Massimo, Tremoli, Elena, Manfredi, Angelo A., Figini, Filippo, Baldissera, Elena, Campana, Lara, Godino, Cosmo, Camera, Marina, Evangelista, Virgilio, Rovere-Querini, Patrizia, Baldini, Mattia, D’Angelo, Armando, Maseri, Attilio, Demetrio, Monica, Bartorelli, Antonio, Maugeri, Norma, Coppi, Giovanni, Sabbadini, Maria Grazia, Marenzi, Giancarlo

2012

Overview

Neutrophils are involved in thrombus formation. We investigated whether specific features of neutrophil activation characterize patients with acute coronary syndromes (ACS) compared to stable angina and to systemic inflammatory diseases. The myeloperoxidase (MPO) content of circulating neutrophils was determined by flow cytometry in 330 subjects: 69 consecutive patients with acute coronary syndromes (ACS), 69 with chronic stable angina (CSA), 50 with inflammation due to either non-infectious (acute bone fracture), infectious (sepsis) or autoimmune diseases (small and large vessel systemic vasculitis, rheumatoid arthritis). Four patients have also been studied before and after sterile acute injury of the myocardium (septal alcoholization). One hundred thirty-eight healthy donors were studied in parallel. Neutrophils with normal MPO content were 96% in controls, >92% in patients undergoing septal alcoholization, 91% in CSA patients, but only 35 and 30% in unstable angina and AMI (STEMI and NSTEMI) patients, compared to 80%, 75% and 2% of patients with giant cell arteritis, acute bone fracture and severe sepsis. In addition, in 32/33 STEMI and 9/21 NSTEMI patients respectively, 20% and 12% of neutrophils had complete MPO depletion during the first 4 hours after the onset of symptoms, a feature not observed in any other group of patients. MPO depletion was associated with platelet activation, indicated by P-selectin expression, activation and transactivation of leukocyte β2-integrins and formation of platelet neutrophil and -monocyte aggregates. The injection of activated platelets in mice produced transient, P-selectin dependent, complete MPO depletion in about 50% of neutrophils. ACS are characterized by intense neutrophil activation, like other systemic inflammatory syndromes. In the very early phase of acute myocardial infarction only a subpopulation of neutrophils is massively activated, possibly via platelet-P selectin interactions. This paroxysmal activation could contribute to occlusive thrombosis.

• Publisher: Public Library of Science,Public Library of Science (PLoS)
• Subject: Acute coronary syndromes / Adult / Aged / Angina / Angina pectoris / Angina, Unstable - immunology / Angina, Unstable - metabolism / Animals / Arteritis / Arthritis / Autoimmune diseases / Autoimmune Diseases - immunology / Autoimmune Diseases - metabolism / Biology / Blood platelets / Cardiac patients / Cardiomyopathy / Cardiovascular disease / Cell activation / Cytometry / Depletion / Diabetes / Disease Models, Animal / Disorders / Female / Flow cytometry / Fractures / Glycoproteins / Heart attack / Heart attacks / Heart failure / Humans / Infarction / Infection / Infectious diseases / Inflammatory diseases / Integrins / Ischemia / Kinases / Leukocytes / Leukocytes (neutrophilic) / Ligands / Male / Medical research / Medicine / Mice / Middle Aged / Monocytes / Myocardial infarction / Myocardial Infarction - immunology / Myocardial Infarction - metabolism / Myocardium / Neutrophil Activation - immunology / Neutrophils / Neutrophils - immunology / Neutrophils - metabolism / P-selectin / P-Selectin - metabolism / Patients / Pattern recognition / Peroxidase / Peroxidase - metabolism / Platelets / Rheumatoid arthritis / Rheumatoid factor / Sepsis / Systemic vasculitis / Thromboembolism / Thrombosis / Vasculitis / White blood cells