Soluble factors in plasma from chronic lymphocytic leukemia (CLL) patients prime neutrophils to release extracellular traps (NETs)

PODAZA E; SABBIONE F; RISNIK D; BORGE M; ALMEJUN B; COLADO A; FERNANDEZ GRECCO H; BEZARES F; TREVANI AS; GAMBERALE, R; GIORDANO, M

Congreso; II Congreso Franco-Argentino de Inmunología.; 2015

We have previously reported that neutrophils from CLLpatients (CLL-PMN) were more prone to form neutrophil extracellular traps (NETs) in vitro compared to neutrophils from healthy donors (HD-PMN). Given that NET formation depends on the production of reactive oxygen species (ROS), we evaluated if CLL-PMN show a higher capacity than HD-PMN to generate ROS in response to PMA. We found no differences in ROS formation evaluated by flow cytometry (n=7). Therefore we explored the possibility that factors in plasma from CLL-patients could prime neutrophils to release NETs. To this aim HD-PMN were isolated by standard procedures and preincubated with plasma from age-matched-HD or CLL-patients for 30 minutes before stimulation with PMA (25 ng/ml) for 4 h. We found higher concentrations of DNA and increased elastase activity in supernatants from PMA-stimulated-HD-PMN incubated in the presence of plasma from CLL patients (PMA alone versus CLLplasma plus PMA: p