Subconjunctival Injection of Mesenchymal Stem Cells for Corneal Wound Healing After Chemical Injury: Impact on Epithelial Coverage, Limbal Ischemia, and Ocular Surface Inflammatory

Purpose: Previous studies in animal models have demonstrated that mesenchymal stem cells (MSCs) are beneficial for reconstructing the ocular surface during corneal wound healing; however, clinical evidence remains scarce. This study aimed to evaluate the clinical safety, feasibility, and preliminary outcomes of subconjunctival umbilical-cord delivered-MSC (UC-MSC) injection as an adjunctive therapy for severe corneal chemical injuries.

Methods: This prospective, single-arm clinical case series enrolled six patients with severe corneal chemical injuries. Human UC-MSCs at passages 5–6 were cultured and verified. A total sample of 4 × 10⁶ cells suspended in 400 μL of 1 × Hanks’ Balanced Salt Solution (HBSS) were subconjunctivally delivered adjacent to the limbus using a 360° circumferential injection technique. Concurrently, all patients underwent amniotic membrane transplantation (AMT) and received a standard 4-week topical regimen (Tobradex, recombinant human epidermal growth factor, and Solcoseryl). Clinical safety, limbal ischemia, inflammatory indices, and epithelial defect areas were assessed through a digital slit-lamp examination.

Results: No localized or systemic adverse events, such as anterior uveitis, progressive ulceration, intraocular infection, or immunological rejection, were observed in any participant. By 4 weeks post-injection, active ocular surface inflammation had significantly decreased in all eyes. Of the five patients with baseline limbal ischemia, four achieved complete revascularization and resolution; the fifth exhibited a marked reduction in ischemia from 100 to 20%. Furthermore, stable corneal re-epithelialization was achieved in five of six eyes, including one with complete paracentral epithelial coverage.

Conclusion: Subconjunctival UC-MSC delivery is a safe and feasible adjunctive therapy for managing severe corneal chemical injuries. This cell-based intervention synergizes with conventional therapies to suppress acute inflammation, rescue limbal perfusion while potentially mitigating subsequent corneal neovascularization, and accelerate the structural reconstruction of the ocular surface microenvironment.