OC 43.3 - Thrombin Shanghai Mutant Grafted by Bacteria-engineered Porous Sponge for Perioperative Bleeding

Monday, June 24, 2024

15:15 – 15:30 ICT

Room: Ballroom B3

Presenting Author(s)

ke Zhang, MS

Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine
shanghai, Shanghai, China (People's Republic)

Co-Author(s)

Xi Wu, MD

Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
Shanghai, Shanghai, China (People's Republic)
LB

Luhan Bao

Ph.D
Department of Orthopaedics, Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 197 Ruijin 2nd Road, Shanghai, 200025, P. R. China.
Shanghai, Shanghai, China (People's Republic)
Changming chen, PhD candidate

Technician
Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
Shanghai, Shanghai, China (People's Republic)
WC

Wenguo Cui

Professor
Department of Orthopaedics, Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 197 Ruijin 2nd Road, Shanghai, 200025, P. R. China.
Shanghai, Shanghai, China (People's Republic)
JD

Jing Dai

Professor
Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
Shanghai, Shanghai, China (People's Republic)

Background: Thrombin directly activated the downstream of the clotting cascade, promptly promoting platelet activation and clot formation. Thrombin Shanghai mutant found in thrombus patients was demonstrated a decreased ability to activate the anticoagulation pathway of protein C, therefore displayed a biased activity toward coagulation compared with wild-type thrombin.

Aims: In this study, by grafting thrombin Shanghai mutant onto nanocellulose, a topical hemostatic wound dressing was developed for therapeutic intervention of coagulation dysfunction to minimize intraoperative and postoperative blood loss.

Methods: Oxidized bacterial nanocellulose (OBNC) was obtained by fermentation of Komagataeibacter xylinus and TEMPO oxidation, then further grafted with thrombin by prokaryotic expression through an amide bond. Hemostatic capacity was evaluated by in vitro hemostatic assay and in vivo liver trauma model. Regeneration ability was assessed by in vitro cell assay and full-thickness skin injury model.

Results: In vitro experiments showed that OBNC-thrombin absorbed water at a rate of 1.70 g/s with a high total pore area, and rapidly enriches platelets and other components to form a barrier and accelerate hemostasis at an early stage. In rat liver trauma model, in vivo coagulation experiments showed that OBNC-thrombin had stronger procoagulant effect than routinely used collagen-hemostatic sponge (COL), and OBNC-thrombin Shanghai had the least blood loss compared to WT and other dressings (Fig. 1). In rat skin injury model, wounds macroscopically recovered better after OBNC-thrombin treatment (Fig. 2A, B). Immunofluorescence and histologic staining demonstrated higher levels of neovascularization and mature blood vessels and a slightly stronger inflammatory response (Fig. 2C-F), as well as a larger collagen volume fraction, indicating the revascularization and re-epithelialization of the wound.

Conclusion(s): OBNC-thrombin Shanghai hemostatic sponge promotes coagulation in the early stage of bleeding and angiogenesis in the long term, which effectively prevents severe perioperative bleeding through intraoperative hemostasis and postoperative repair.