Application of Mouse Normal Small Intestinal Organoid Cytokine Panel in the Study of Crohn's Disease Mechanisms

I. The Value of Small Intestinal Organoids in Intestinal Disease Research

Small intestinal organoids are miniature tissue structures self-organized from small intestinal adult stem cells under three-dimensional culture conditions, capable of highly replicating the physiological structure and cellular composition of the intestinal epithelium, including intestinal stem cells, Paneth cells, goblet cells, enteroendocrine cells, and absorptive enterocytes, among others. This culture system mimics the in vivo stem cell microenvironment by adding specific cytokine combinations, maintaining the self-renewal and multi-directional differentiation potential of stem cells. Small intestinal organoid models hold significant value in the study of intestinal infections and the mechanisms of inflammatory bowel disease (IBD), and also provide an ideal in vitro research platform for analyzing host-microbe interactions in the gut. In basic research, using the mouse normal small intestinal organoid cytokine kit can simulate the growth microenvironment of small intestinal organoids, offering an important tool for studying the intestinal epithelium's response mechanisms to pathogens.

II. The Potential Association Between Crohn's Disease and Mycobacterium avium

Crohn's disease (CD), as a chronic recurrent inflammatory bowel disease, has always been a research focus in the field of intestinal diseases. Mycobacterium avium subspecies paratuberculosis (MAP) is considered a potential trigger, but the mechanisms linking the two and the early response patterns of the intestinal epithelium remain unclear. To explore the potential association between MAP infection and Crohn's disease, the research team constructed a MAP-infected mouse small intestinal organoid model. Transcriptome analysis and comparison with Crohn's disease patient-derived mouse models revealed a large number of overlapping differentially expressed genes and enriched pathways, confirming that infection can induce intestinal epithelium to produce inflammatory features highly similar to Crohn's disease. The study identified Mmp7 as a key molecular marker linking MAP infection to Crohn's disease-like pathology, with its mediated epithelial remodeling and inflammatory responses significantly activated in both models. Additionally, the TLR2 signaling pathway was found to regulate the directional recruitment of macrophages to infected organoids, providing new research insights and potential therapeutic targets for Crohn's disease.

III. Establishment of the Mouse Small Intestinal Organoid Infection Model

To investigate the potential association between MAP infection and Crohn's disease, the research team pioneered the construction of a mouse small intestinal organoid infection model. Successfully cultured mouse small intestinal organoids could stably expand and maintain in vitro. After co-culturing with fluorescently labeled MAP, live-cell confocal imaging showed that bacterial load within the organoids significantly increased over time; quantitative analysis further confirmed a progressive increase in MAP numbers. When MAP was directly microinjected into the Matrigel between two organoids, directional migration of basolateral cells toward the bacterial location was observed, indicating that epithelial cells possess the ability to sense and respond to bacterial stimuli. Cytoskeleton staining results verified that MAP could successfully invade and localize within mouse small intestinal organoids, establishing a reliable in vitro infection model for subsequent mechanistic studies. During this process, the mouse normal small intestinal organoid cytokine kit provided standardized conditions for the stable culture and expansion of organoids, supporting the construction and maintenance of the infection model.

IV. Cellular Response Mechanisms Induced by Mycobacterium avium Infection

MAP can actively invade intestinal epithelial cells and induce directional cellular migration. The study found that MAP can invade intestinal epithelial cells from the basolateral side and establish intracellular colonization, while also inducing directional migration of epithelial cells toward the bacterial location, revealing the active response capability of the intestinal epithelium to pathogens. This phenomenon suggests that intestinal epithelial cells are not just a physical barrier but can actively sense bacterial stimuli and respond directionally. Using the mouse small intestinal organoid infection model, the spatiotemporal dynamics of epithelial cell migration toward infection sites can be observed and recorded in real-time, providing a unique perspective for studying host-pathogen interactions. Organoids cultured with the mouse normal small intestinal organoid cytokine kit exhibit excellent physiological activity and response capability, making them an ideal tool for studying such cellular behaviors.

V. The Role of the TLR2 Signaling Pathway in Macrophage Recruitment

The study clarified that the TLR2 signaling pathway regulates the directional recruitment of macrophages to infected organoids. Macrophages can directionally migrate toward MAP-infected organoids, form clusters, and eventually infiltrate the organoids, a process regulated by the TLR2 signaling pathway, simulating early immune events of granuloma formation. This discovery reveals the molecular mechanism by which the innate immune system recognizes MAP infection and the interactions between immune cells and epithelial cells. In co-culture systems, observing the directional migration and infiltration of immune cells when macrophages are co-cultured with infected organoids provides a controllable in vitro model for studying early intestinal inflammatory events. The organoid culture system supported by the mouse normal small intestinal organoid cytokine kit can be used to establish such immune-epithelial co-culture models, exploring the molecular mechanisms of immune cell recruitment.

VI. Discovery of Mmp7 as a Key Molecular Marker

The study identified Mmp7 as a key molecular marker linking MAP infection to Crohn's disease-like inflammation. MAP infection can activate core inflammatory pathways such as TNF-α/NF-κB and IL-6/JAK/STAT3, with IBD signaling pathways significantly enriched in both infected organoids and Crohn's disease mouse models. Mmp7 was significantly upregulated in both models, with its mediated epithelial remodeling and inflammatory responses being core features shared by both, providing potential therapeutic targets for Crohn's disease. Transcriptome analysis revealed a large number of overlapping differentially expressed genes and enriched pathways between infected organoids and Crohn's disease models, confirming that infection can induce intestinal epithelium to produce inflammatory features highly similar to Crohn's disease. This discovery not only reveals the molecular link between infection and disease but also provides a theoretical basis for developing new therapeutic strategies.

VII. Which Manufacturers Provide the Mouse Normal Small Intestinal Organoid Cytokine Kit?

Nanjing UA-Bio Biotechnology Co., Ltd. (UA-Bio) has independently developed the "Small Intestinal Organoid Cytokine Set, Mouse", a high-performance cytokine kit specifically designed for constructing and maintaining mouse normal small intestinal organoids. This kit employs an optimized cytokine combination to simulate the microenvironment signals for small intestinal crypt stem cell proliferation and differentiation, supporting the long-term expansion and organoid formation of mouse small intestinal stem/progenitor cells. It provides standardized and reliable solutions for research in intestinal development, nutrient absorption mechanisms, and drug evaluation.

Nanjing UA-Bio Biotechnology Co., Ltd. is always committed to providing cutting-edge, high-quality core reagents and tools for immunology, cell therapy, and innovative drug development. For detailed technical parameters, validation data, or specific application inquiries regarding the "Small Intestinal Organoid Cytokine Set, Mouse" (Catalog No.: UA090043), please feel free to contact us.