Exploration of the Therapeutic Protocols and Underlying Molecular Mechanisms of Autologous Platelet-Rich Plasma in the Treatment of Deep Second-Degree Burns.

BACKGROUND

Platelet-rich plasma (PRP) has been widely applied in burn wound management due to its high concentration of bioactive growth factors. However, inconsistent clinical outcomes and the lack of standardized protocols regarding timing, frequency, and leukocyte content limit its broader clinical adoption.

AIMS: This study aimed to evaluate the therapeutic efficacy of PRP under different application protocols in patients with deep second-degree burns and to explore the underlying molecular mechanisms, with the goal of informing standardized, evidence-based PRP treatment strategies.

PATIENTS/

METHODS

Thirty-three patients with deep second-degree burns were enrolled and randomly assigned to five groups: a standard PRP group, a saline control group, an early intervention PRP group, a high-frequency PRP group, and a leukocyte-poor PRP group. Clinical outcomes included wound healing time, wound coverage rates at 2 and 3 weeks, bacterial culture positivity, and Vancouver Scar Scale scores at 3 months. Wound tissue and exudate samples were collected at predefined time points for immunohistochemical analysis of macrophage phenotypes (M1/M2) and quantification of growth factors (VEGF, PDGF, TGF-β).

RESULTS

Compared with the control group, PRP treatment was associated with a shorter wound healing time, increased early wound coverage, reduced bacterial culture positivity, and improved scar outcomes. Early PRP intervention and the use of leukocyte-poor PRP appeared to further enhance healing efficiency, which may be related to accelerated polarization of macrophages from the pro-inflammatory M1 phenotype toward the anti-inflammatory M2 phenotype. In contrast, high-frequency PRP administration resulted in higher local growth factor levels but did not translate into additional clinical benefit; this lack of efficacy may be attributable to excessive expression of transforming growth factor-β (TGF-β), which could potentially counteract optimal tissue repair.

CONCLUSIONS

PRP is an effective adjunctive therapy for small-area deep second-degree burns. Early application and leukocyte-poor PRP appear optimal, whereas indiscriminately increasing treatment frequency is not recommended. Controlled modulation of PRP-derived growth factors may be key to maximizing therapeutic benefit.