Exploring the Impact of Extraplatelet Content on Fibrin-Based Scaffold Performance for Regenerative Therapies

Abstract

This study investigated the impact of increased extraplatelet content on the tissue regenerative capacity of platelet-rich plasma (PRP)-derived fibrin scaffolds. Comparative analyses were performed between a "balanced protein-concentrate plasma" (BPCP) and a standard PRP (sPRP), focusing on platelet and fibrinogen content, scaffold microstructure, and functional performance. Growth factor (GF) release kinetics from the scaffolds were quantified via ELISA over 10 days, while scaffold biomechanics were evaluated through rheological testing, indentation, energy dissipation, adhesion, and assessments of coagulation dynamics, biodegradation, swelling, and retraction. Microstructural analysis was conducted using scanning electron microscopy (SEM), with fiber diameter and porosity measurements. The results demonstrated that BPCP scaffolds released significantly higher amounts of GFs and total protein, especially beyond 24 h (* p < 0.05). Despite a delayed coagulation process (** p < 0.01), BPCP scaffolds exhibited superior structural integrity and cushioning behavior (* p < 0.05). SEM revealed thicker fibers in BPCP scaffolds (**** p < 0.0001), while adhesion and biodegradation remained unaffected. Notably, BPCP scaffolds showed reduced retraction after 24 h and maintained their shape stability over two weeks without significant swelling. These findings indicate that enhancing the extraplatelet content in PRP formulations can optimize fibrin scaffold performance. Further preclinical and clinical studies are warranted to evaluate the therapeutic efficacy of BPCP-derived scaffolds in regenerative medicine.

Keywords: biodegradation; biomaterial; biomechanic; fibrin scaffold; platelet-rich plasma.

Figure 1

Morphological analysis of sPRP and BPCP scaffolds. (A) SEM images of sPRP (left) and BPCP (right). Scale bar 10 µm. (B) Fiber diameter size in sPRP and BPCP is expressed in nm. (C) Porosity is represented by the number of pores per µm². Fiber diameter and number of pores were measured using the software ImageJ v 1.51W. Error bars = standard deviation (n = 4). Statistically significant differences were calculated using Student’s t test (**** p < 0.0001).

Figure 2

Coagulation kinetics of sPRP and BPCP scaffolds. The duration of the different phases of the clotting process is shown in the figure: start of coagulation (A), clotting process (B) and end of coagulation (C). Time is expressed in minutes in all graphs. Error bars = standard deviation (n = 9). Statistically significant differences were calculated using Student’s t test (** p < 0.01; **** p < 0.0001).

Figure 3

Mechanical properties of sPRP and BPCP scaffolds. The graphs show the sweep amplitude data showing the tanδ score (viscoelasticity) (A), Young’s modulus (stiffness) (B), the dissipation energy (cushioning) (C), the adhesion capacity (D) of the sPRP and BPCP formulations. Error bars = standard deviation (n = 4–7). Statistically significant differences were calculated using Student’s t test (* p < 0.05; ** p < 0.01).

Figure 4

Retraction and swelling ratios of sPRP and BPCP scaffolds. The retraction ratio (%) of sPRP and BPCP scaffolds was measured up to 24 h (A), and swelling ratio (%) were determined up to 240 h (B). Error bars = standard deviation (n = 5–11). Statistically significant differences were calculated using Student’s t test (* p < 0.05; ** p < 0.01).

Figure 5

Biodegradation rates of sPRP and BPCP scaffolds. The PRP formulations were exposed to 0.25 μg mL⁻¹ tissue plasminogen-activator (tPA) for one week. Error bars = standard deviation (n = 5). Statistically significant differences were calculated using Student’s t test.

Figure 6

Total protein released from sPRP and BPCP scaffolds. Total protein concentration (g dL⁻¹) released from both plasma fibrin clot formulations over a 10-day period are shown. Error bars = standard deviation (n = 3). Statistically significant differences were calculated using Student’s t test (* p < 0.05; ** p < 0.01).