Journal of Asia Pacific Aesthetic Sciences

Abstract: Articular cartilage defects affect millions globally, with 50% progressing to post-traumatic osteoarthritis within 20 years. Current treatments require invasive bone marrow or adipose tissue harvesting, increasing patient morbidity and costs. Peripheral blood-derived mesenchymal stromal cells (PB-MSCs) offer a minimally invasive alternative through simple blood collection yet remain underexplored. This study investigates the synergistic potential of PB-MSCs combined with platelet-rich plasma (PRP) for hyaline cartilage regeneration in a scaffold-free approach, advancing accessible regenerative medicine. New Zealand White rabbits (N=30) with bilateral full-thickness cartilage defects (4mm diameter) were randomized into five groups: PB-MSC alone, PRP alone, PB-MSC+PRP combination, defect control, and normal control. PB-MSCs were validated through immunophenotyping and tri-lineage differentiation against bone marrow-MSCs and adipose tissue-MSCs. PRP was prepared, achieving 5-fold platelet concentration. Intra-articular injections (1×10⁶ cells) were administered weekly for three weeks. Outcomes were assessed at 3 and 6 months using Modified Brittberg and Modified O'Driscoll histological scoring (H&E, Safranin-O, type II collagen immunohistochemistry) and quantitative morphometric analyses by four blinded observers. PB-MSCs demonstrated positive MSC characteristics with high CD90 expression (>99%) and successful tri-lineage differentiation, validating their therapeutic potential. Combinatorial PB-MSC+PRP treatment achieved superior cartilage regeneration with progressive improvement from 3 to 6 months. At 6 months, the combination therapy achieved Modified O'Driscoll scores of 21.00±1.36 compared to defect controls (8.00±1.00, p<0.0001), significantly outperforming individual PB-MSC (19.00±0.88) and PRP (13.00±1.26) therapies. Histological analyses confirmed hyaline-like cartilage formation with positive type II collagen expression and proteoglycan deposition, demonstrating near-complete defect filling. This scaffold-free, blood-based approach represents a significant advancement in orthopedic regenerative medicine, offering accessible, cost-effective treatment through minimally invasive procedures. The validated synergistic efficacy establishes immediate clinical translation potential, addressing global healthcare challenges particularly in resource-limited settings.