PB0172 - Interleukin 1 – beta increases fibrin polymerization potential and increases ex vivo clot density

Sunday, June 23, 2024

13:45 – 14:45 ICT

Room: Exhibition Hall

Co-Author(s)

Arun Saini, MD MS

Associate Professor
Baylor College of Medicine
Houston,, Texas, United States
LG

Luis Gardea

Research Assistant
Department of Pediatrics/Division of Critical Care Medicine/Baylor College of Medicine/Texas Children's Hospital/CTRID
Houston, Texas, United States
JC

Justin Courson

Instructor
Baylor College of Medicine/CTRID
Houston, Texas, United States
SR

Stefanie Rivera

Research Assistant
Baylor College of Medicine/CTRID
Houston, Texas, United States
DS

Deepika Subramanyam

Post Doctoral Associate
Baylor College of Medicine/CTRID
Houston, Texas, United States
MM

Marina Martinez-Vargas

Instructor
Baylor College of Medicine/CTRID
Houston, Texas, United States
KV

K. Vinod Vijayan

Associate Professor
Baylor College of Medicine/CTRID
Houston, Texas, United States
Miguel A. Cruz

Professor
Baylor College of Medicine/CTRID
Houston, Texas, United States

Presenting Author(s)

Trung C. Nguyen

Associate Professor
Department of Pediatrics, Division of Critical Care Medicine, Baylor College of Medicine/Texas Children's Hospital/CTRID
Houston, Texas, United States

Background: Interleukin-1beta (IL-1ß) is significantly elevated in sepsis. IL-1ß can bind to fibrin(ogen), and this binding increases IL-1ß inflammatory activities (1). Previously, we showed that ex vivo clots from COVID-septic patients are denser & more lysis-resistant compared to those of non-COVID sepsis (2). We hypothesize that IL-1ß will directly bind to fibrin(ogen) to potentiate fibrin polymerization and increase the fibrin clot’s structure to a denser clot.

Aims: To investigate if IL-1ß can bind to and alter the structure of fibrin clot.

Methods: Fibrin polymerization assays were conducted to evaluate the potential of fibrin clot formation with and without human recombinant IL-1ß at concentrations of 0, 500, 1000, and heat denatured 500 pg/mL. Ex-vivo clots were formed by adding 100 and 200 pg/mL of human recombinant IL-1ß and fluorescent fibrinogen (Alexa Fluor 647) to healthy donor plasma. These clots were then incubated with fluorescent anti-IL-1b antibodies (Alexa Fluor 488) and washed with a wash buffer before being observed under a Laser Scanning Confocal Microscopy.

Results: We found maximum fibrin clot formation potential was increased by 15% (p < 0.01) and 19% (p < 0.01) with 500 and 1000 pg/mL of IL-1ß, respectively, compared to control (Fig 1). Denatured 500 pg/mL of IL-1b did not increase fibrin clot formation potential (p=0.08). We observed increased clot density with increasing concentrations of 100 and 200 pg/mL of IL-1ß, and incorporated IL-1ß (Red dots) was visualized into ex-vivo fibrin clots (Fig 2).

Conclusion(s): IL-1ß can directly engage with fibrin clot, increase fibrin clot formation potential and increase the density of the fibrin clot. These studies suggest that IL-1ß can have a direct role in the clot formation during sepsis-induced coagulopathy. Clinical trial of inhibiting IL-1ß in sepsis-induced multiple organ dysfunction is underway (NCT05267821).

1 PMID:15039285; 2 PMID:35170535