PB1348 - Impact of Neutrophil extracellular traps (NETs) on endothelial cell behavior and procoagulant proteins up-regulation

Tuesday, June 25, 2024

13:45 – 14:45 ICT

Room: Exhibition Hall

Co-Author(s)

SM

Shahsoltan Mirshahi

Main Researcher
Prospective Research, Diagnostica Stago
Gennevilliers, Ile-de-France, France
MS

Mehenni Safaa

Researcher
CAP-Paris Tech., INSERM U1275, Université Paris Cité, Hôpital Lariboisière
Paris, Ile-de-France, France
AD

Ahamada Dorian

resercher
Prospective Research, Diagnostica Stago
Gennevilliers, Ile-de-France, France
AI

Aldybiat Iman

Researcher
CAP-Paris Tech., INSERM U1275, Université Paris Cité, Hôpital Lariboisière
Paris, Ile-de-France, France
Cs

Crepaux sullyvan

Resercher
Prospective Research, Diagnostica Stago
Gennevilliers, Ile-de-France, France
SJ

Soria Jeannette

Researcher
CAP-Paris Tech., INSERM U1275, Université Paris Cité, Hôpital Lariboisière
paris, Ile-de-France, France
GC

Geneviève Contant

Prospective Research Director
R&D - Diagnostica Stago
Gennevilliers, Ile-de-France, France
MP

Marc Pocard

Researcher,
CAP-Paris Tech., INSERM U1275, Université Paris Cité, Hôpital Lariboisière
75010, Ile-de-France, France

Presenting Author(s)

Massoud Mirshahi, M. D., Ph. D

Team Director
CAP-Paris Tech., INSERM U1275, Université Paris Cité, Hôpital Lariboisière
Paris, Ile-de-France, France

Background: Cancer-related thrombosis is the second leading cause of death among patients with malignant diseases. However, the mechanisms involved in the occurrence of thrombotic events remain unexplored.

Aims: To clarify the impact of the histone H3 of NETs on endothelial cell behavior for their abaility to modulate the phenotype of human endothelial cells, the main regulator of hemostasis.

Methods: Plasma cancer patients with peritoneal carcinomatosis were enrolled from Pitie-Salpetriere hospital. Human endothelial cells (HUVEC) were used, purified Histone-3 was purchased from Sigma and Human H3 and H4 ELISA assays (CliniSciences) were performed on patient’s plasma. NET formation from whole blood was obtained by LPS activation. The impact of nuclear protein on HUVEC cell was performed by Real-time cell proliferation (Xcelligence). Cytotoxicity of H3 on HUVEC was analyzed by TUNEL. Impact of nuclear protein on HUVEC (in serum free) was analyzed by proteomic analysis.

Results: Endothelial cells that are co-cultured with histone H3 change their form and their contract. This co-culture is associated with cell detachment after 24 hours of treatment. Purified H3 as well as plasma of patients with high content in H3, exert a cytotoxic effect on HUVEC endothelial cells in vitro, through an apoptosis induction. H3 switches the profile of endothelial cells towards a procoagulant phenotype. By proteomic analysis, a total of 5387 proteins were identified across all patient samples. Among these proteins, 115 cytosol proteins and 49 membrane proteins were overexpressed in the presence of histone H3 on endothelial cells. Among these proteins: complement subunits, FXII, Kininogen, KrasGTPase, IgG heavy chain, Apolipoprotein, Plastin, uPA and serine protease inhibitors were up regulated.

Conclusion(s): Our study highlights the capacity of histone H3 to modulate both 1) the procoagulant cell phenotype and 2) the cause of damage and detachment of endothelial cells from the blood vessel wall, thereby altering the vascular structure.