Subcutaneous Injection of Allogeneic Adipose-Derived Mesenchymal Stromal Cells in Psoriasis Plaques: Clinical Trial Phase I

OBJECTIVE: Mesenchymal stromal cells (MSCs) play immunomodulatory role in various autoimmune diseases. Previous pre-clinical and clinical studies have shown that MSCs could be a therapeutic modality for psoriasis. However, the mechanisms of treatment and its possible side effects are under investigation. In this study, the safety and probable efficacy of injecting allogeneic adipose-derived mesenchymal stromal cells (ADSCs) in psoriatic patients were evaluated. MATERIALS AND METHODS: In this phase I clinical study with six months of follow-up, total number of 1×10(6) or 3×106 cells/cm(2) of ADSCs were injected into the subcutaneous tissue of each plaque as a single dose in three males and two females (3M/2F) with a mean age of 32.8 ± 8.18. The primary outcome was safety. Changes in clinical and histological indexes, the number of B and T lymphocytes in local and peripheral blood, and serum levels of inflammatory cytokines were assessed. Paired t test was used to compare variables at two time points (baseline and six months after injection) and repeated measures ANOVA test was utilized for variables at three time points in follow-up visits. RESULTS: No major adverse effects such as burning, pain, itching, or any systemic side effects were observed following ADSCs injection, and the lesions showed slight to considerable improvement after injection. The mRNA expression levels of pro-inflammatory factors were reduced in the dermis of the patients after injection. The increased expression level of Foxp3 transcription factor in the patient blood samples suggested modulation of inflammation after ADMSCs administration. Six months after the intervention, no major side effects were reported, but skin thickness, erythema, and scaling of the plaques, as well as the PASI score, were decreased in majority of patients. CONCLUSION: Our study suggested that ADSC injection could be considered as a safe and effective therapeutic approach for psoriatic plaques (registration number: IRCT20080728001031N24).