A novel cryoprecipitate-enriched PRP (Cryo-PRP) gel with enhanced mechanical strength and regenerative capacity accelerates enterocutaneous fistula healing.

INTRODUCTION

Enterocutaneous fistula (ECF) remains a major clinical challenge due to its complex pathophysiology, high recurrence, and limited non-surgical options. Platelet-rich plasma (PRP) has demonstrated regenerative potential, but its limited mechanical strength restricts its application in high-output fistulas. To overcome this limitation, we developed a cryoprecipitate-enriched PRP (Cryo-PRP) with enhanced fibrinogen content and gel stability.

METHODS

Cryo-PRP was prepared by cryoprecipitation of conventional PRP. Characterization included fibrinogen quantification, thromboelastography (TEG), and scanning electron microscopy (SEM). Therapeutic efficacy was assessed in a rat ECF model by evaluating fistula closure, histological changes, and expression of angiogenic and inflammatory markers.

RESULTS

Cryo-PRP exhibited significantly higher fibrinogen levels (5.26 ± 0.78 g/L vs. 2.58 ± 0.49 g/L, P < 0.001) and greater clot firmness (TEG-MA: 37.8 ± 2.2 mm vs. 28.7 ± 1.3 mm, P < 0.001) compared with standard PRP. SEM revealed a denser and more organized fibrin network in Cryo-PRP gels. In vivo, Cryo-PRP accelerated wound healing, enhanced epithelialization, preserved crypt architecture, and reduced inflammation. Immunostaining demonstrated increased neovascularization (CD34), upregulation of regenerative markers (α-SMA, CD31, VEGF, PCNA), and suppression of TNF-α expression.

DISCUSSION: Cryo-PRP demonstrates superior mechanical and biological properties over conventional PRP, effectively promoting tissue regeneration and reducing inflammation in an ECF model. These findings support Cryo-PRP as a safe, autologous, and minimally invasive therapeutic strategy for ECF management.