Abstract: Objective · To analyze the value of multi-parametric magnetic resonance imaging (MRI) of knee cartilage in evaluating the efficacy of allogeneic human adipose-derived mesenchymal progenitor cells (haMPCs) on the treatment of osteoarthritis. Methods · Twenty-two patients with knee osteoarthritis were treated with haMPCs and randomly divided into three dose groups, low, medium and high, according to the medication dose. Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score and carotid multi-parametric MRI scans which include 3D-SPGR, T2-mapping, T2*-mapping, T1ρ-mapping and DWI were performed before and after 48 weeks’ treatment. The WOMAC score, cartilage volume, T2 value, T2* value, T1ρ value and apparent diffusion coefficient (ADC) value were recorded. The index changes and the inter-group differences were compared. Results · A total of 18 candidates completed the WOMAC score evaluations and MRI examinations twice. After treatment, except for cartilage volume, WOMAC score, T2 value, T2* value, T1ρ value and ADC value of all subjects were significantly different those before treatment (PPPP0.026) while there was no significant changes in cartilage volume (P>0.05). The inter-group comparisons showed that there was no significant difference before treatment (P>0.05), but there was a significant difference of T1ρ in cartilage between the high-dose group and the low-dose group (P0.012) after treatment. Conclusion · Multi-parametric cartilage MRI can be used to evaluate the efficacy of haMPCs treatment on osteoarthritis, which may be more sensitive than cartilage volume assessment.

Key words: knee osteoarthritis, magnetic resonance imaging (MRI), mesenchymal progenitor cell