Intrarenal injection of mesenchymal stem cell for treatment of lupus nephritis in mice - a pilot study

The current project is to explore feasibility of direct intra-renal injection of human bone marrow derived mesenchymal stem cells (hMSC) for treatment of lupus nephritis in mice. The treatment protocol involved aged male BXSB (20 weeks) injected with 1 × 10⁶ hMSC unilaterally under the renal capsule. Mice were harvested after 10 weeks follow-up for postmortem exam. Controls included untreated age matched male BXSB and healthy C57Bl/6. At the end of follow-up period, the survival of treated BXSB was 10 folds higher at 62.5% compared to survival of untreated control at 6.3%. The survival of C57Bl/6 remained at 100% with or without similar treatment. The renal pathology review was most significant for decreased tissue inflammation in treated BXSB compared to untreated controls. Renal tissue expression of IL-1b, IL17 were decreased and CTLA-4 was increased by RT PCR among treated compared to untreated BXSB. Thus, direct delivery of hMSC by intrarenal injection is a promising route for treatment of lupus nephritis as shown in this xenogeneic model. Further studies -using expanded numbers of mice to include other lupus strains- are warranted to investigate the mechanisms involved and to optimize treatment protocol for safety and efficacy.