HtrA1의 혈전 특이적 단백분해 활성은 본래의 구조 단백질, 상처 혈전 및 상처 치유 과정을 방해하지 않는다 = The Thrombus-Specific Proteolytic activity of HtrA1 without disrupting native structural proteins, wound clots, and wound healing process

다국어 초록 (Multilingual Abstract)

Thrombus formation is central to cardiovascular and cerebrovascular diseases, yet current thrombolytic agents such as tissue-type plasminogen activator (tPA) are limited by a narrow therapeutic window and serious side effects, including intracerebral hemorrhage and impaired wound healing. These drawbacks arise from plasmin’s nonspecific proteolysis of fibrin, fibrinogen, and extracellular matrix (ECM) proteins.
Here, we explored high-temperature requirement protein A1 (HtrA1) as a potential plasmin-independent thrombolytic enzyme. In silico analyses suggested that HtrA1 binds fibrin but not fibrinogen, and that ECM components differentially inhibit HtrA1 through its PDZ domain, whereas they activate plasmin. Biochemical and enzyme kinetics assays further indicated that HtrA1 selectively degrades fibrin without affecting fibrinogen or vascular proteins, in contrast to plasmin.
Functionally, ex vivo assays showed that HtrA1 efficiently lysed both fresh (12 h) and aged (24 h) clots, while Alteplase lost activity in older clots. Tail bleeding and wound healing models suggested that HtrA1 preserved normal hemostasis and clot integrity, unlike Alteplase. In a photothrombotic mouse ischemic stroke model, HtrA1 appeared to restore cerebral blood flow (CBF), reduce infarct volume, preserve neuronal morphology, and minimize intracerebral hemorrhage compared with Alteplase at equivalent doses.
These findings suggest that HtrA1 may function as a thrombus-specific thrombolytic enzyme with activity against aged clots and a potentially improved safety profile, highlighting its promise as a candidate for next-generation thrombolytic therapy.

목차 (Table of Contents)

• List of Figures ii
• Abbreviation list iii
• Abstract iv
• Introduction 1
• Materials and methods 4
• Results 13
• Discussion 27
• References 30
• Figures 39
• 국문 초록 57