Introduction

Anti-tumor necrosis factor (anti-TNF) therapy can be safely withdrawn in a subset of patients with long-standing quiescent Crohn’s disease. However, accurately identifying which patients belong to this subset remains challenging. This study aimed to identify mRNA profiles associated with relapse risk and prolonged remission after anti-TNF withdrawal in CD patients in microscopic remission. Here, we leveraged the NanoString 360 Immuno Panel, which provides significant advantages over bulk sequencing by offering highly multiplexed, sensitive, and automated gene expression analysis of the tumor microenvironment without enzymatic amplification to contrast mucosal immune signatures in patients with and without three-year relapse following anti-TNF withdrawal.

Aims & Methods

Patients in the CEASE cohort with mucosal biopsies at anti-TNF withdrawal who later relapsed were matched to those in sustained remission based on biopsy location (ileum or colon).¹ For patients with a relapse, only biopsies corresponding to the site of disease activity at relapse were selected for mRNA analysis. Microscopic remission at baseline was confirmed by a blinded expert pathologist. Relapse was defined as endoscopically confirmed inflammation, while sustained remission was defined as no relapse during follow-up. 785 mRNA’s of the nCounter Host Response Profiling panel were measured, and corrected to the expression of household genes (IO 360 panel). The 3 most up- and downregulated relapse-associated mRNAs were identified by first selecting on significance (p<0.05), followed by ranking based on log2 fold change. mRNA levels were normalized to the cohort mean, and the score was calculated as the sum of the most upregulated divided by the sum of the most downregulated mRNA’s. Hence, a Cox regression and ROC analysis were performed to examine the relationship between the score and relapse.

Results

Eleven patients who relapsed were matched to 11 in sustained remission based on biopsy location (7 colon, 4 ileum). Median age was 40 years, 45% male, with median anti-TNF exposure of 5.2 years. Baseline characteristics were comparable between groups; of note, 6/11 (55%) in the relapse group vs 4/11 (36%) in sustained remission received concomitant immunomodulators (p=0.67). Median follow-up was 3.3 years (IQR 2.6) and median time to relapse 15.8 months (IQR 9.5). The score, based on the 3 most up- and downregulated mRNAs (IFITM1, PIK3CA, RBPJ, IRF3, THOP1, NEU1), was higher in the relapse group (median 2.94 (IQR 1.2-6.0) vs 0.36 (IQR 0.24-0.56), p = 0.001) and associated with relapse risk (HR per one-point 1.25, 95% CI 1.08–1.45). The AUC was 0.89, with the best cut-off of 0.98 based on the Youden index, resulting in a sensitivity of 0.83 and specificity of 1.

Conclusion

This study identifies a specific mucosal mRNA profile associated with relapse risk after anti-TNF withdrawal in Crohn disease patients in clinical, endoscopic and microscopic remission. This profile reliably distinguishes high-risk patients in this case-control study but requires further validation. Furthermore, it provides insights in mucosal immune mechanisms, suggesting that strong innate immunity may protect against CD relapse, whereas adaptive immunity is associated with risk for relapse.

References

1. Ten Bokkel Huinink S, de Jong DC, Nieboer D, et al. Validation and update of a prediction model for risk of relapse after cessation of anti-TNF treatment in Crohn's disease. Eur J Gastroenterol Hepatol 2022;34:983-992.

Introduction

Despite recent advances in IBD therapy, there is a need for novel effective, safe oral drugs. Mufemilast has demonstrated sustained efficacy and safety in plaque psoriasis¹. Here we report the efficacy and safety of Mufemilast at 12 weeks from this phase 2 trial (NCT05486104).

Aims & Methods

Patients with moderate to severe UC were randomized (1:1:1) to placebo (n=31), mufemilast 45mg (n=31) or 60mg (n=30) twice daily (BD) for 12 weeks. Eligibility criteria required participants to have a modified Mayo score (mMS) of 4-9, including an endoscopy score of ≥ 2 , inadequate /loss of response to conventional therapy (5-ASA, Steroids, immunomodulators), or biologics (anti-TNF, anti-integrin, anti-interleukin 12/23). Stable co-treatment with oral 5'ASAs and corticosteroids was permitted if it was stable for at least ≥2 weeks before microscopy within the screening period and needed to remain stable for the duration of the study. Patients with positive Quantiferon tests were also eligible. Efficacy definitions were according to FDA guidance².

Results

Conclusion

Mufemilast efficacy and safety were consistent across subgroups regardless of previous biologic use, suggesting Mufemilast is a viable potential future treatment option in patients with moderate to severe UC that breaks through the current 20% ceiling for clinical remission. A phase 3 study will be conducted to confirm these results.

References

¹Jones, C.; Zhang, J.; Wang, L.; Dai, X.; Wang, H.; Bi, X.; Duan, X.; Meng, Z.; Tian, Z.; Xu, A.; et al. A Double-Blind, Placebo-Parallel Controlled Phase III Clinical Study of the Efficacy and Safety of Hemay005 Tablets in Patients with Moderate to Severe Chronic Plaque Psoriasis in China. Arthritis Rheumatol ACR Converg. 2023, 75.
² Food and Drug Administration. Ulcerative Colitis: Developing Drugs for Treatment. Guidance for Industry - Draft Guidance; 2022. Accessed May 11, 2025. https://www.fda.gov/media/158016/download

Introduction

Helicobacter pylori (H. pylori) infection is a major cause of gastric diseases, with the virulence factor CagA carried by exosomes playing a crucial role in regulating inflammation. Ferroptosis and M1 polarization are key mechanisms in promoting inflammation, yet the role of CagA in inducing macrophage ferroptosis and M1 polarization to exacerbate gastric mucosal inflammation remains unclear.

Aims & Methods

CagA-positive (CagA+) and CagA-negative (CagA-) H. pylori strains were co-cultured with gastric epithelial cells, and their supernatants were collected. Exosomes were isolated using ultracentrifugation to obtain CagA+Exo and CagA-Exo. Changes in macrophage M1/M2 polarization markers and ferroptosis markers were analyzed under CagA+Exo and CagA-Exo treatment. The activation of the JAK/STAT1 signaling pathway was assessed by Western blot, and STAT1 expression in the nucleus was evaluated using a nuclear protein extraction kit. Chromatin immunoprecipitation (ChIP) was used to identify the binding site of STAT1 on the SLC7A11 promoter. Biopsy samples from the gastric mucosa of gastritis patients infected with CagA+ or CagA- H. pylori were analyzed for macrophage polarization and ferroptosis markers.

Results

Exosomal CagA was found to induce macrophage M1 polarization and ferroptosis, with the ferroptosis inhibitor SLC7A11 playing a key role in CagA-induced ferroptosis. Exosomal CagA activated the JAK/STAT1 signaling pathway, leading to M1 polarization and ferroptosis. Additionally, CagA+Exo increased nuclear STAT1 expression, which subsequently bound to the SLC7A11 promoter to regulate its transcription. In gastric mucosa biopsies from CagA+ H. pylori-infected gastritis patients, increased levels of iNOS (a marker of M1 polarization) and decreased expression of SLC7A11 were observed.

Conclusion

Our findings indicate that exosomal CagA promotes macrophage M1 polarization and ferroptosis through the JAK/STAT1 signaling pathway. This study provides new insights and potential therapeutic targets for H. pylori-associated gastritis.