title: Circulating platelet-leukocyte aggregates: a marker of microvascular injury in diabetic patients.
abstract: Diabetes is associated with multiple disorders including metabolic, cellular and blood disturbances leading to vascular complications. Increased circulating levels of platelet-leukocyte aggregates (PLA) have been described in several thrombotic diseases. In this study, we have evaluated circulating PLA in diabetic patients and we have investigated whether they may be a marker of vascular complications. Using flow cytometry assay, we have quantified PLA percentages in 65 diabetics including 20 patients with type I and 45 with type II diabetes, and 25 healthy subjects. Specific labelling identified platelet-polymorphonuclear aggregates (PPA) and platelet-monocyte aggregates (PMA). We have observed a significant increase of PPA and PMA levels in diabetics (22+/-12% and 45+/-18%, respectively) compared to controls (7+/-4% and 19+/-10%, respectively) (p<0.01). However, both PPA and PMA values were similar in the two diabetes types. Circulating PPA and PMA were significantly enhanced in diabetics with vascular lesions (PPA: 24+/-13%; PMA: 50+/-18%) than in diabetics without vascular lesions (PPA: 18+/-8%; PMA: 38+/-15%) (p<0.05 and p<0.01). Patients with PPA>18% and/or PMA>38% showed a more important vascular injury (OR: 6; 95% CI: 1.6-23). Increased PMA circulating rate is particularly correlated to retinopathic injury (OR: 19; 95% CI: 2.3-154). Our findings established a relationship between increased circulating PLA levels, particularly PMA, and the incidence of microvascular complications in diabetes. They reinforce the concept of pro-inflammatory cells involvement in diabetic retinopathy pathogenesis and their link with thrombotic process.
authors.affiliation: Service d'Hématologie Biologique, Hôtel-Dieu, 1 Parvis Notre Dame 75181, Paris Cedex 04, Université Pierre et Marie Curie (Paris VI), France. ismail.elalamy@tnn.aphp.fr
authors.forename: I
authors.initials: I
authors.lastname: Elalamy
authors.forename: T
authors.initials: T
authors.lastname: Chakroun
authors.forename: G T
authors.initials: GT
authors.lastname: Gerotziafas
authors.forename: A
authors.initials: A
authors.lastname: Petropoulou
authors.forename: F
authors.initials: F
authors.lastname: Robert
authors.forename: A
authors.initials: A
authors.lastname: Karroum
authors.forename: F
authors.initials: F
authors.lastname: Elgrably
authors.forename: M-M
authors.initials: MM
authors.lastname: Samama
authors.forename: M
authors.initials: M
authors.lastname: Hatmi
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers; D001792:Blood Platelets / Q000473:pathology*; D002449:Cell Aggregation; D003920:Diabetes Mellitus / Q000097:blood*; D003930:Diabetic Retinopathy / Q000097:blood* / Q000150:complications; D005260:Female; D006801:Humans; D007962:Leukocytes / Q000473:pathology*; D008297:Male; D008833:Microcirculation / Q000473:pathology; D008875:Middle Aged; D010974:Platelet Aggregation; D014652:Vascular Diseases / Q000097:blood* / Q000150:complications