Stem cell transplantation for induction of remission in medically refractory Crohn's disease

Safety and efficacy of stem cell therapy for Crohn's disease: an umbrella review of systematic reviews

BACKGROUND

Crohn's disease is a chronic, relapsing form of inflammatory bowel disease marked by severe gastrointestinal inflammation and a broad range of debilitating symptoms. Despite advances in medical treatments, achieving sustained remission remains challenging for many patients. This umbrella review aims to consolidate evidence from various systematic reviews to evaluate the efficacy and safety of stem cell therapies in treating Crohn's disease.

METHODS

This review followed the Joanna Briggs Institute methodology and adhered to PRISMA guidelines. A literature search of PubMed, Web of Science, Embase, and the Cochrane Library covered records up to 20 April 2024. Only systematic reviews and meta-analyses on stem cell therapy for Crohn's disease were considered. Data were extracted and analyzed for clinical efficacy indicators like remission induction and safety metrics, including adverse events and mortality rates.

RESULTS

Sixteen systematic reviews were included, spanning studies conducted between 2009 and 2023. Stem cell therapy showed a pooled risk ratio (RR) of 1.299 (95% CI: 1.192-1.420) for clinical remission, indicating a 29.9% increased likelihood of remission compared to controls. The pooled RR for healing perianal Crohn's disease was 1.358 (95% CI: 1.13-1.631), suggesting a 35.8% increased likelihood of healing. A pooled RR of 1.481 (95% CI: 1.036-2.116) shows a 48.1% higher immediate fistula closure rate with stem cell therapy. For long-term outcomes, a RR of 1.422 (95% CI: 1.091-1.854) indicates a 42.2% increased likelihood of maintaining closure. However, stem cell therapy did not significantly impact Crohn's Disease Activity Index (CDAI) (RR: 1.154, 95% CI: 0.193-6.883) and Perianal Disease Activity Index (PDAI) scores (mean difference at 12 weeks: -0.505, 95% CI: -2.481 to 1.471; mean difference at 24 weeks: -0.338, 95% CI: -1.638 to 0.963). The safety profile was comparable to conventional therapies, with a pooled RR of 0.972 (95% CI: 0.739-1.278) for adverse events and 1.136 (95% CI: 0.821-1.572) for serious adverse events.

CONCLUSION

Stem cell therapy offers significant progress in treating Crohn's disease, particularly in complex cases, by improving fistula closure rates and suggesting potential as a supplementary therapy. Its safety profile aligns with conventional treatments, yet ongoing clinical trials are crucial to optimize its use. Continual research will enable healthcare providers to tailor more effective treatment strategies for this challenging condition.

Efficacy and safety of stem cell therapy for fistula management: an overview of existing systematic reviews

BACKGROUND

Fistulas, abnormal connections between two anatomical structures, significantly impact the quality of life and can result from a variety of causes, including congenital defects, inflammatory conditions, and surgical complications. Stem cell therapy has emerged as a promising alternative due to its potential for regenerative and immunomodulatory effects. This overview of systematic reviews aimed to assess the safety and efficacy of stem cell therapy in managing fistulas, drawing on the evidence available.

METHODS

This umbrella review was conducted following the Joanna Briggs Institute (JBI) methodology to assess the efficacy and safety of stem cell therapy for treating various types of fistulas. A comprehensive search was performed across multiple electronic databases including PubMed, Embase, Cochrane Register, and Web of Science up to 5 May 2024. Systematic reviews focusing on stem cell therapy for fistulas were included, with data extracted on study design, stem cell types, administration methods, and outcomes. The quality of the reviews was assessed using the AMSTAR 2 tool, and meta-analyses were conducted using R software version 4.3.

RESULTS

Nineteen systematic reviews were included in our umbrella review. The stem cell therapy demonstrated by significant improvements in clinical remission rates, with a relative risk (RR) of 1.299 (95% CI: 1.192-1.420). Stem cell therapy enhanced fistula closure rates, both short-term (RR=1.481; 95% CI: 1.036-2.116) and long-term (RR=1.422; 95% CI: 1.091-1.854). The safety analysis revealed no significant increase in the risk of adverse events with stem cell therapy, showing a pooled RR of 0.972 (95% CI: 0.739-1.278) for general adverse events and 1.136 (95% CI: 0.821-1.572) for serious adverse events, both of which indicate a safety profile comparable to control treatments. Re-epithelialization rates also improved (RR=1.44; 95% CI: 1.322-1.572).

CONCLUSION

Stem cell therapy shows promise as an effective and safe treatment for fistulas, particularly in inducing remission and promoting closure of complex fistulas. The findings advocate for further high-quality research to confirm these benefits and potentially incorporate stem cell therapy into standard clinical practice for fistula management. Future studies should focus on long-term outcomes and refining stem cell treatment protocols to optimize therapeutic efficacy.

Hyperbaric oxygen therapy ameliorates intestinal and systematic inflammation by modulating dysbiosis of the gut microbiota in Crohn's disease

BACKGROUND

Dysbiosis of the gut microbiota is pivotal in Crohn's disease (CD) and modulated by host physiological conditions. Hyperbaric oxygen therapy (HBOT) is a promising treatment for CD that can regulate gut microbiota. The relationship between HBOT and the gut microbiota in CD remains unknown.

METHODS

CD patients were divided into an HBOT group (n = 10) and a control group (n = 10) in this open-label prospective interventional study. The fecal samples before and after HBOT were used for 16 S rRNA gene sequencing and fecal microbiota transplantation (FMT). A colitis mouse model was constructed using dextran sulfate sodium, and intestinal and systematic inflammation was evaluated. The safety and long-term effect of HBOT were observed.

RESULTS

HBOT significantly reduced the level of C-reactive protein (CRP) (80.79 ± 42.05 mg/L vs. 33.32 ± 18.31 mg/L, P = 0.004) and the Crohn's Disease Activity Index (CDAI) (274.87 ± 65.54 vs. 221.54 ± 41.89, P = 0.044). HBOT elevated the declined microbial diversity and ameliorated the altered composition of gut microbiota in patients with CD. The relative abundance of Escherichia decreased, and that of Bifidobacterium and Clostridium XIVa increased after HBOT. Mice receiving FMT from donors after HBOT had significantly less intestinal inflammation and serum CRP than the group before HBOT. HBOT was safe and well-tolerated by patients with CD. Combined with ustekinumab, more patients treated with HBOT achieved clinical response (30%vs.70%, P = 0.089) and remission (20%vs.50%, P = 0.160) at week 4.

CONCLUSIONS

HBOT modulates the dysbiosis of gut microbiota in CD and ameliorates intestinal and systematic inflammation. HBOT is a safe option for CD and exhibits a promising auxiliary effect to ustekinumab.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR2200061193. Registered 15 June 2022, https://www.chictr.org.cn/showproj.html?proj=171605 .

Efficacy and safety of stem cell therapy for Crohn's disease: a meta-analysis of randomized controlled trials

PURPOSE

Small-scale clinical trials have provided evidence suggesting the effectiveness of stem-cell therapy (SCT) for patients diagnosed with Crohn's disease (CD). The objective of the research was to systematically assess the effectiveness and safety of SCT for individuals diagnosed with CD through a comprehensive review and meta-analysis.

METHODS

A search was conducted in Medline (PubMed), CENTER (Cochrane Library), and Embase (Ovid) to find randomized controlled trials (RCTs) that assessed the impact of SCT on the occurrence of clinical remission (CR) and severe adverse events (SAE) among patients diagnosed with CD. The Cochrane Q test and estimation of I2 were used to assess heterogeneity among studies. After incorporating heterogeneity, a random-effects model was employed for data pooling.

RESULTS

Overall, 12 RCTs involving 632 adult patients with medically refractory CD or CD-related fistula were included. In comparison with placebo or no treatment, SCT showed a greater likelihood of CR (odds ratio [OR] 2.08, 95% CI 1.39-3.12, p < 0.001) without any notable heterogeneity (I2 = 0%). Consistent results were observed in subgroup analyses based on study design, patient diagnosis, source and type of stem cells, and follow-up durations, with all p-values for subgroup analyses being greater than 0.05. The occurrence of SAE was similar among patients assigned to SCT and the placebo/no treatment cohorts (OR 0.70, 95% CI 0.37-1.33, p = 0.28; I2 = 0%).

CONCLUSIONS

For patients with medically refractory CD or CD-related fistula, SCT may be an alternatively effective and safe treatment.