Elucidating crosstalk between intestinal epithelium and immune cells using human gut derived organoids as a model

Intestinal epithelium is a very good model of normal physical cell environment and the complex interactions between different cell types like epithelial and immune cells. The epithelial layer is of great interest because it is made of different types of cells. The cellular building block of this enteric surface is composed of diverse cells: enterocytes adapted for absorptive metabolic and digestive functions; goblet cells, which secrete mucin and play a main role in the protection against infection. Paneth cells, at the bottom of the crypts, which secretes anti-microbial peptides and chemosensory epithelial cells known as Tuft cells. All of these epithelial cells are derived from the differentiation of the intestinal stem cell located at the bottom of the crypts.  Researcher culture stem cells from normal or diseased tissue and can be embedded with extracellular matrix to create mini-organs, called organoids.

Bildet kan inneholde: lilla, organisme, gj?re, fiolett, terrestrisk plante.

Figure 1: Human duodenum section: Stained for Lysozyme C in crypts ( Paneth cell marker-green color), Ulex Europaeus Agglutinin I (UEA I- red color) binds to α-linked fucose residues on Goblet cells, EPCAM – (Purple color) Epithelial cell adhesion molecule) and DAPI ( blue color) binds to nuclear DNA. 20-x tile scan of section was captured using Zeiss LSM 880 confocal microscope.  We routinely check expression of epithelial and immune cell markers in normal and metaplastic gut sections.

 

Organoids are an excellent tool to define epithelial effector responses. Specific features such as organoid size, morphology, and cellular composition are essential parameters. These parameters identify whether a particular treatment leads to induction of repair processes that are needed after the loss of tissue due to damage or infection. Macrophages reside in virtually all organs and play a key role in host defense and tissue homeostasis. Tissue macrophages are particularly important in the gut where they defend the body against a wide variety of pathogens and toxic substances. However, gut macrophages also contribute to pathology. Aberrant activation of macrophages plays an important role in disorders such as inflammatory bowel disease (Ulcerative colitis and Crohn's disease).

 

Main objectives for the master thesis project:

  1. Establishment of human gut organoids to study intestinal niche.
  2. Establishment of ex vivo model to study inflammation in organoids- macrophages co-culture system.

Study design and methods:

Here, we will use mixed methods research to combine quantitative and qualitative data analysis to investigate different research objectives. For example, RNA-seq analysis will be helpful to combine quantitative transcriptome analysis. In addition, confocal laser scanning microscopy will be employed for both qualitative observation and quantitative measurement of different parameters of human gut duodenal and colon organoids. In the last four years, I have gained the necessary expertise in these techniques to study mouse intestinal epithelium and thus, it will be a smooth transition to now do human gut epithelium tissue-based studies. "Overall, master students will learn organoids culture from human gut tissue, Immunofluorescence microscopy, Immunohistochemistry, flow cytometry, real-time qRT-PCR, Western blotting, RNA isolation method for RNA sequencing and other techniques." As well as student will learn how to proceed with bioinformatics analysis of the Immunofluorescence images and how to interpret the data.

 

Routine workflow in our laboratory and for this master thesis project:

We work at the Department of Pathology, Rikshospitalet Oslo. We study the human gut under both normal and cancer conditions. To do this, we get human gut tissue from the surgery department at Rikshospitalet. After that, we isolate different cell types from the duodenum and colonic tissue depending on the projects. For this project, I separate duodenal and colonic crypts from tissue as the project involves generating and maintaining human gut organoids. After establishing organoid cultures from different patient tissue, downstream analysis using RNA techniques, immunohistochemistry, Immunofluorescent staining of organoids, and other methods are performed.

Bildet kan inneholde: organisme, gj?re, musikk instrument.

Figure 2: Routine workflow for organoids generation from human gut tissue in our laboratory.

Supervisor for this project: Naveen Parmar Ph.D. email: naveen.parmar@medisin.uio.no

Current position: Postdoctoral Fellow, Rikshospitalet, Department of Pathology, University of Oslo

 Co-supervisor: Diana Domanska , Researcher                               

Group Leader:  Frode Lars Jahnsen

Please read here more about our research:

OUH - Mucosal Immunology and Cancer Research

Visit our laboratory website for more information

Publisert 4. apr. 2022 13:31 - Sist endret 11. apr. 2022 09:41

Veileder(e)

Omfang (studiepoeng)

60