Background/Objectives: Evidence is needed on the real-world outcomes of upadacitinib in patients with ulcerative colitis. This systematic review and meta-analysis evaluated the real-world effectiveness of upadacitinib for active UC. Methods: The primary outcome was clinical remission evaluated at week 8. Secondary outcomes included response, steroid-free remission, biochemical remission, colectomy, and safety. A random-effects meta-analysis model was used to calculate the pooled effect sizes (percentages or incidence rates) of effectiveness and safety outcomes. Results: Twenty-four studies with 1388 patients were included. Ninety-four percent of patients had previously failed biologics or Janus kinase inhibitors (JAKi), including 53.2% with tofacitinib. Clinical remission at week 8 was achieved in 68.4% of patients (95% confidence interval 55.5–80.2). Clinical remission was achieved in 48.3%, 71.1%, and 64.6% of patients at weeks 2 to 6, 12 to 16, and 24 to 36, respectively. Response was achieved in 72.6%, 82.1%, and 78.7% of patients at weeks 2 to 6, week 8, and weeks 12 to 16, respectively. Steroid-free remission was achieved in 39% of patients at week 8. Upadacitinib results were unaffected by prior biologic or JAKi failure. Mean fecal calprotectin level decreased from 1485.0 µ/g at baseline to 454.8 µ/g post-treatment (p < 0.01). The mean CRP level decreased from 12.3 mg/L at baseline to 4.4 mg/L post-treatment (p = 0.02). The incidence rates of colectomy, serious adverse events, and herpes zoster were 13.3, 2.3, and 1.7 per 100 patient-years, respectively. Conclusions: This meta-analysis confirms the effectiveness and safety of upadacitinib in a highly treatment-refractory population of UC patients.

Background: Local injection of darvadstrocel, a suspension of expanded adipose‐derived allogenic mesenchymal stem cells, has been used for treatment‐refractory perianal fistulas in Crohn's disease (CD).Objective: This study aimed to investigate efficacy and safety of darvadstrocel for complex perianal fistulas in CD.Methods: A systematic search was conducted through April 2024 in relevant databases for observational studies evaluating darvadstrocel. A random‐effects meta‐analysis model was used to calculate the pooled effect sizes (proportions or incidence rates [IRs]) with 95% confidence intervals (CIs) of effectiveness and safety outcomes. The risk of bias was evaluated using the Joanna Briggs Institute Critical Appraisal Tool. The I² value assessed heterogeneity. Sensitivity and subgroup analyses were also conducted.Results: Twelve studies were included with 595 patients. The pooled rate of patients achieving clinical remission, defined as fistula healing, was 68.1% at month 6 (95% CI 63.4–72.7) and 77.2% (95% CI 70.1–83.8) at month 12. Combined remission, defined as clinical remission and absence of collections >2 cm confirmed by magnetic resonance imaging, was reported in 60.6% and in 69.7% of patients at months 6 and 12, respectively. The rate of patients with treatment failure, defined as no clinical remission at the last follow‐up (mean 18.7 months; SD 9.9), was 34.5%. Failure rate was independent of follow‐up time (p = 0.85). For effectiveness outcomes, between‐study heterogeneity was negligible. Subgroup analysis indicated that none of the covariates modified the treatment effect. Pooled IRs per 100 patient‐years of adverse events (AE), serious AEs, perianal abscesses, and reoperations were 19.6, 3.2, 16.9 and 7.1, respectively.Conclusion: Evidence from observational studies supports the efficacy and safety of darvadstrocel for complex perianal fistulas in CD. Studies have reported high fistula healing rates that can be sustained long‐term in most patients, with negligible between‐study heterogeneity, as well as a favorable safety profile.

Background: A causal relationship between Crohn's disease (CD) and asthma is reported, but the underlying mechanisms are not fully understood. We sought to investigate the role of IgE and IgE‐mediated pathways in the pathophysiology of CD. Methods: 20 CD patients, 10 allergic patients without inflammatory bowel disease, and 10 healthy donors (HD) were included in the study. Total serum IgE was quantified by ELISA. Circulating IgE ⁺ and FcεRIα ⁺ immune cells, as well as specific CD4 ⁺ T cell populations, were determined by flow cytometry. Gene set enrichment signatures from available single‐cell (sc)RNAseq datasets of the intestine from CD patients were analyzed. Purified plasmacytoid dendritic cells (pDCs) from CD patients were cocultured with naïve CD4 ⁺ T cells to assess Tregs generation. Results: CD patients, similar to allergic non‐CD patients, displayed significantly higher numbers of circulating IgE ⁺ or FcεRIα ⁺ immune cells than HD. The percentage of blood IgE ⁺ or FcεRIα ⁺ pDCs was significantly higher in CD than HD and similar to allergic non‐CD patients. CD patients showed significantly higher numbers of effector memory CD4 ⁺ T cells and lower numbers of FOXP3 ⁺ Tregs than HD. scRNAseq data from CD patients confirmed that Tregs imbalance and overactivation of IgE‐mediated pathways take place also in gut tissues of children and adults, suggesting IgE could interfere in the pDC‐Tregs axis. In vitro functional experiments demonstrated that IgE‐crosslinking on pDCs from CD patients impairs Treg generation, which was restored by the anti‐IgE mAb omalizumab. Conclusions: IgE might play an unprecedented role in CD by impairing the capacity of pDCs to generate Tregs, which could represent a novel mechanism contributing to CD to be exploited for alternative therapeutic interventions.

The adult mammalian heart has been demonstrated to be endowed with low but real turnover capacity, especially for cardiomyocytes, the key functional cell type. The source, however, of that turnover capacity remains controversial. In this regard, we have defined and characterized a resident multipotent cardiac mouse progenitor population, Bmi1+DR (for Bmi1+ Damage-Responsive cells). Bmi1+DR is one of the cell types with the lowest ROS (Reactive Oxygen Species) levels in the adult heart, being particularly characterized by their close relationship with cardiac vessels, most probably involved in the regulation of proliferation/maintenance of Bmi1+DR. This was proposed to work as their endothelial niche. Due to the scarcity of Bmi1+DR cells in the adult mouse heart, we have generated an immortalization/dis-immortalization model using Simian Vacuolating Virus 40-Large Antigen T (SV40-T) to facilitate their in vitro characterization. We have obtained a heterogeneous population of immortalized Bmi1+DR cells (Bmi1+DR^IMM) that was validated attending to different criteria, also showing a comparable sensitivity to strong oxidative damage. Then, we concluded that the Bmi1-DR^IMM population is an appropriate model for primary Bmi1+DR in vitro studies. The co-culture of Bmi1+DR^IMM cells with endothelial cells protects them against oxidative damage, showing a moderate depletion in non-canonical autophagy and also contributing with a modest metabolic regulation.