Mesenchymal Stem Cell Injection in Crohn’s Disease Strictures: A Phase I–II Clinical Study

Background and Aim Mesenchymal stem cells [MSCs] have anti-inflammatory and anti-fibrotic properties and could be a potential therapy for Crohn’s disease [CD] strictures. In this phase I–II pilot trial, we assessed safety and efficacy of local MSC injection to treat CD strictures. Methods CD patients with a short [less than 5 cm in length] non-passable stricture accessible by ileocolonoscopy were included. Allogenic bone-marrow derived MSCs were injected in the four quadrants of the stricture. Adverse events and clinical scores were evaluated at each follow-up visit and endoscopy and magnetic resonance enterography were performed at baseline, Week [W]12 and W48. The main judgement criterion for efficacy was the complete [defined by the ability to pass the ileocolonoscope] or partial [defined by a diameter increase] resolution of the stricture at W12. Second efficacy criteria included assessment of the stricture at W48 and evolution of clinical scores at W12 and W48. Results We performed 11 MSC injections in 10 CD patients [three primary and seven anastomotic strictures; one stricture injected twice]. MSC injections were well tolerated but four hospitalisations for occlusion were reported. At W12, five patients presented a complete or partial resolution of the stricture [two complete and three partial]. Seven patients were re-evaluated at W48 [one dilated, one operated, and one lost to follow-up] and four patients had a complete resolution. The evolution of clinical scores between W0, W12, and W48 was not statistically significant. Conclusions MSCs injection in CD stricture was well tolerated and may offer a benefit.

Stem Cell, Fibrin Glue, and Normal Saline on Partially Torn Tendons: A Randomized Controlled Trial

Background: Tendons have limited reparative ability and perform a relatively simple mechanical function via the extracellular matrix. Thus, the injured tendon might successfully treated by stem cell transplantation. We performed a randomized, controlled study to investigate the effects of mesenchymal stem cell injection for treating partial tears in the supraspinatus tendon.Methods: We enrolled 24 patients with shoulder pain lasting more than 3 months and partial tears in the supraspinatus tendon. Participants were assigned to three groups: stem cells in fibrin glue, normal saline/fibrin glue mixture, and normal saline only, with which intra-lesional injection was performed. Pain at activity and rest, shoulder function and tear size were evaluated. For safety measures, laboratory tests were taken and adverse events were recorded at every visit. Participants were followed up at 6, 12 weeks, 6, 12 months and 2 years after injection. The primary outcome measure was the improvement in pain at activity at 3 months after injection. Results: Twenty-three patients were included in the final analysis. Primary outcome did not differ among groups (p = 0.35). A mixed effect model revealed no statistically significant interactions. Only time significantly predicted the outcome measure. All participants reported transient pain at the injection site. There were no differences in post-injection pain duration or severity. Safety measures did not differ between groups, and there were no persistent adverse events.Conclusions: Stem cell injection into supraspinatus partial tears in patients with shoulder pain lasting more than 3 months was not more effective than control injections. (ClinicalTrials.gov Identifier: NCT02298023)

First Immunohistochemical Evidence of Human Tendon Repair Following Stem Cell Injection: A Case Report and Review of Literature

Current clinical treatment options for symptomatic, partial-thickness rotator cuff tear (sPTRCT) offer only limited potential for true tissue healing and improvement of clinical results. In animal models, injections of adult stem cells isolated from adipose tissue into tendon injuries evidenced histological regeneration of tendon tissue. However, it is unclear whether such beneficial effects could also be observed in a human tendon treated with fresh, uncultured, autologous, adipose derived regenerative cells (UA-ADRCs). A specific challenge in this regard is that UA-ADRCs cannot be labeled and, thus, not unequivocally identified in the host tissue. Therefore, histological regeneration of injured human tendons after injection of UA-ADRCs must be assessed using comprehensive, immunohistochemical and microscopic analysis of biopsies taken from the treated tendon a few weeks after injection of UA-ADRCs.