Two New Subtypes of Crohn's Disease: The Key to Personalized Therapy

Crohn's disease has long remained a mystery for scientists due to its diversity and complexity. However, recent research has enabled scientists to create a more accurate model of the disease, which will help overcome existing limitations in the development of new therapies. The discovery of two new subtypes of Crohn's disease brings us closer to creating personalized treatment methods tailored to each patient.

About the Study

In this study, scientists developed an innovative approach to studying Crohn's disease (CD) by creating patient-derived organoids (PDO). These miniature models of the intestine allowed for an in-depth analysis of the molecular mechanisms underlying the disease and opened new avenues for developing effective therapeutic strategies.

The study, conducted at the Inflammatory Bowel Disease Center at the University of California, San Diego, included 34 patients with CD, 10 patients with ulcerative colitis (UC), and 9 healthy volunteers. The ages of patients with CD ranged from 20 to 74 years, with 52% being male and 74% belonging to the Caucasian race. Most patients (64%) provided tissue samples from the colon or ileocolon, and 23% were biologically naïve. The Montreal classification was used to classify CD, revealing a predominance of subtypes B1 (35%), B2 (39%), and B3 (26%).

Researchers created organoids from adult stem cells obtained through colon biopsies from patients with CD. The resulting collection of organoids became a valuable resource for studying the disease. Scientists conducted a comprehensive analysis of the organoids using multi-omics approaches, including transcriptome and genome analysis. Additionally, data obtained from the organoid analysis were compared with clinical characteristics of patients and data on the organoids' responses to various drugs.

To deeply study the cellular mechanisms of the disease, high-throughput methods were employed, such as single-cell analysis and RNA sequencing. A total of 154,000 genetic variants associated with CD or inflammatory bowel diseases (IBD) were analyzed. Phenotyping of the organoids was assessed using light and quantitative fluorescence microscopy, immunofluorescence, trans-epithelial electrical resistance (TEER), transmission electron microscopy (TEM), confocal imaging, flow cytometry, enzyme-linked immunosorbent assay (ELISA), as well as methods for assessing cell proliferation, apoptosis, and aging.

The results of the study identified new molecular mechanisms underlying the development of CD and characterized various phenotypes of organoids reflecting the heterogeneity of the disease. The data obtained open new prospects for developing personalized therapeutic strategies aimed at correcting disrupted molecular processes in the intestines of patients with CD.

Study Results

Scientists were able to identify two distinct subtypes of the disease: immunodeficient infectious type (IDICD) and stress-induced aging fibrosthenotic type (S2FCD). Each of these subtypes is characterized by unique molecular features and pathophysiological mechanisms.

Immunodeficient Infectious Type (IDICD)

IDICD demonstrated a weakened immune response to bacterial infections. Organoids of this type are characterized by impaired function of Paneth cells, responsible for maintaining the intestinal microbiome, as well as increased cell proliferation and death. Mutations in the NOD2 and ATG16L1 genes, associated with an increased risk of developing CD, are often found in patients with IDICD.

Stress-Induced Aging Fibrosthenotic Type (S2FCD)

S2FCD exhibited significant oxidative stress and premature aging of intestinal cells. Organoids of this type demonstrate morphological changes such as thickening and narrowing of the intestinal wall, as well as mutations in the YAP1-IL-18 gene associated with inflammation.

Personalized Therapeutic Strategies

Researchers tested various drugs on both subtypes. For instance, pacritinib (a JAK inhibitor) successfully slowed the aging process in S2FCD organoids, while metformin showed a similar effect. On the other hand, the drug PAR5359 improved bacterial clearance in IDICD organoids but had no effect on aging. Probiotics and postbiotics also demonstrated a positive effect on intestinal barrier function.

Conclusion

The results of the study highlight the importance of a personalized approach to treating CD. The identification of different subtypes of the disease and understanding their molecular characteristics open new opportunities for developing more effective and safer therapeutic strategies. The use of organoids as a disease model allows for studying the effects of various drugs on patient cells and accelerating the process of developing new medications.