Pilot trial of intravenous autologous culture-expanded mesenchymal stem cell transplantation in multiple sclerosis.

BACKGROUND: Mesenchymal stem cells (MSCs) exhibit immunomodulatory, tissue-protective, and repair-promoting properties in vitro and in animals. Clinical trials in several human conditions support the safety and efficacy of MSC transplantation. Published experience in multiple sclerosis (MS) is modest. OBJECTIVE: To assess feasibility, safety, and tolerability and explore efficacy of autologous MSC transplantation in MS. METHODS: Participants with relapsing-remitting multiple sclerosis (RRMS) or secondary progressive multiple sclerosis (SPMS), Expanded Disability Status Scale score 3.0-6.5, disease activity or progression in the prior 2 years, and optic nerve involvement were enrolled. Bone-marrow-derived MSCs were culture-expanded and then cryopreserved. After confirming fulfillment of release criteria, 1-2 × 106 MSCs/kg were thawed and administered IV. RESULTS: In all, 24 of 26 screened patients were infused: 16 women and 8 men, 10 RRMS and 14 SPMS, mean age 46.5, mean Expanded Disability Status Scale score 5.2, 25% with gadolinium-enhancing magnetic resonance imaging (MRI) lesions. Mean cell dosage (requiring 1-3 passages) was 1.9 × 106 MSCs/kg (range, 1.5-2.0) with post-thaw viability uniformly ⩾95%. Cell infusion was tolerated well without treatment-related severe or serious adverse events, or evidence of disease activation. CONCLUSION: Autologous MSC transplantation in MS appears feasible, safe, and well tolerated. Future trials to assess efficacy more definitively are warranted.

Interplay of glucagon-like peptide-1 and transforming growth factor-beta signaling in insulin-positive differentiation of AR42J cells.

The differentiation of pancreatic exocrine AR42J cells into insulin-expressing endocrine cells has served as an important model for both endogenous in vivo beta-cell differentiation as well as potential application to beta-cell engineering of progenitor cells. Exogenous activin, possibly working through intracellular smad 2 and/or smad 3, as well as exogenous exendin-4 (a long-acting glucagon-like peptide-1 agonist) have both been shown to induce insulin-positive/endocrine differentiation in AR42J cells. In this study, we present evidence of significant interplay and interdependence of these two pathways as well as potential synergy between the pathways. In particular, insulin-positive differentiation seems to entail an exendin-4-induced drop in smad 2 and elevation in smad 3 in RNA levels. The latter appears to be dependent on endogenous transforming growth factor (TGF)-beta isoform release by the AR42J cells and may serve as a mechanism to promote beta-cell maturation. The drop in smad 2 may mediate early endocrine commitment. The coapplication of exogenous exendin-4 and, specifically, low-dose exogenous TGF-beta1 led to a dramatic 20-fold increase in insulin mRNA levels, supporting a novel synergistic and codependent relationship between exendin-4 signaling and TGF-beta isoform signaling.