Liver Regeneration Following Thermal Ablation Using Nanocarrier Mediated Targeted Mesenchymal Stem Cell Therapy

Purpose: To test the efficacy of nanocarrier (NC) mediated mesenchymal stem cell (MSC) therapy for liver regeneration following thermal ablation of porcine livers.

Materials and methods: Liver radiofrequency ablation was performed in 18 swines divided into MSC, MSC + NC and control groups. The test groups received infusion of MSC or MSC + NC labeled with enhanced green fluorescent protein (eGFP) via hepatic artery. MSC + NC group had MSCs coated with dendrimer nanocarrier complexed with I-Domain of lymphocyte function-associated antigen-1 (LFA-1). Nanocarriers direct homing of MSCs by binding to its counterpart protein, intercellular adhesion molecule-1 (ICAM-1), which is overexpressed at the periablation margins from inflammation. Ablation cavity reduction by CT volumetry was used as surrogate marker for liver regeneration. Cell proliferation was assessed with Ki67 and HepPar-1 stains. GFP identified MSC derived cells.

Results: Total number of ablations in control animals were 13 across 4 animals. In the MSC group, there were 23 ablations across 6 animals, and in MSC + NC group there were 21 ablations across 6 animals. Ablation cavity volume reduction from day 0 to 30 were 64.4 ± 15.0%, 61.5 ± 12.9% and 80.3 ± 9.4% for control, MSC and MSC + NC groups, respectively (MSC + NC vs MSC: p < 0.001, MSC + NC vs. control: p = 0.001). GFP⁺ cell count at margins was 426.8 ± 193.2 for MSC group and 498.6 ± 235.2 for MSC + NC group (p = 0.01). The mean Ki67 and HepPar-1 staining at margins were 9.81 ± 4.5% and 6.12 ± 4.2% for MSC + NC group versus 7.59 ± 3.7% and 5.09 ± 3.7% for MSC group, respectively (P < 0.001 and P = 0.09, respectively).

Conclusion: Nanocarrier-mediated MSC therapy promotes liver regeneration by engrafting MSCs at ablation margins, potentially making liver-directed therapy viable for patients with severe liver dysfunction. This technology may also benefit other solid organs.