POS1146 LOW MOLECULAR WEIGHT HEPARINS INTERFERE WITH NEUTROPHIL ACTIVATION AND NET GENERATION IN HIGH-RISK PREGNANT PATIENTS WITH ANTIPHOSPHOLIPID SYNDROME

Background Neutrophil activation and the generation of neutrophils extracellular traps (NETs) contribute to vascular damage thrombosis in antiphospholipid syndrome (aPS). We reported that Low molecular weight heparin (LMWH) prevent neutrophil induced by P-selectin expressed activated platelets [1, 2] jeopardize healthy subjects ability generate NETs mobilize granule contents [3]. Objectives To investigate whether LMWH, used on empirical bases high-risk patients, regulate neutrophil/platelet interaction pregnant women. Methods Here we report preliminary data from a prospective monocentric study which was assessed sixteen women treated with LMWHs, or without aPS at 12, 24 32 weeks gestation. Patients were studied again when feasible after pregnancy completion. Sixteen women, ten outside Systemic Lupus Erythematosus served as controls. Results Platelets activated, increased expression tissue factor. All patients successfully completed pregnancy. Abnormalities evident pathological assessment placentae despite treatment LMWHs. The associated significantly reduced: i) platelet/neutrophil interaction, heterotypic aggregates; ii) factor; iii) platelet prototypic DAMP, HMGB1; iv) accumulation blood byproducts NET formation/catabolism, such myeloperoxidase-DNA complexes. was, contrast, unaffected. Conclusion results indicate activation/interaction, may reflect detrimental intravascular immune events leading complications, abate References [1]Maugeri N et al. Prevention platelet-polymorphonuclear leukocyte interactions: new clues antithrombotic properties parnaparin, low heparin. Haematologica. 2005; 90(6):833-9. [2]Maugeri Parnaparin, low-molecular-weight heparin, prevents P-selectin-dependent formation platelet-leukocyte aggregates human whole blood. Thromb Haemost. 2007 Jun;97(6):965-73. doi: 10.1160/th06-12-0680. [3]Manfredi AA heparins induction autophagy traps. Pharmacol Res. 2017 Sep;123:146-156. 10.1016/j.phrs.2016.08.008 Acknowledgements: NIL. Disclosure Interests None Declared.