Supervisors: Prof. David Gally, Dr Cristina Esteves, Dr Xavier Donadeu
Project Description:
Bacterial resistance to antibiotics is well recognised as a major threat to animal and human health and there is an urgent need to find alternatives to the generalized use of antibiotics. Approaches currently under consideration involve the use of novel antibacterials and the administration of compounds that boost the innate immune system. Excitingly, Mesenchymal Stem/Stromal Cells (MSCs) were recently found to possess antimicrobial activity as well as immunomodulatory and tissue healing effects [1]. As such, MSCs are now being actively explored as novel tools for combating infection in humans and, only recently, also in animals. However, the actual mechanism(s) responsible for the therapeutic effects of MSCs as well as the conditions under which MSCs display optimal antimicrobial activity remain largely unknown. We have shown in previous studies using the horse [2], a clinically relevant large animal model, that MSCs produce the antimicrobial Lipocalin-2 and express cytokines that can modulate the activity of innate immune cells (e.g. neutrophils and macrophages), and moreover that MSCs from different body sources have different antibacterial potential [1]. Therefore, elucidating the potential of MSCs as antimicrobials against strains which can commonly acquire antibiotic resistance (Escherichia coli and Staphylococcus aureus) may lead to novel strategies to combat this major problem in domestic animals as well as humans.
A limitation to the successful development of novel antimicrobial approaches is the lack of physiologically-relevant ex-vivo models of infection for testing new therapies without the need to use experimental subjects. In this regard, organoids, miniaturized versions of organs which resemble the physiology of the native tissue, provide a novel and exciting alternative [3]. Using such cutting-edge technology, this project will aim to generate organoids from tissues naturally targeted by infection in animals and humans (lung, uterus) which will then be use to model and test the effects of MSCs on infection caused by Escherichia coli and Staphylococcus aureus.
Using established large animals models in our laboratories (equine, bovine) this project will have the following specific objectives:
1) To compare the antibacterial properties of MSCs from different tissue origins (Bone marrow, lung and endometrium) and establish the conditions under which MSCs display optimal antimicrobial activity.
2) To develop ex-vivo infection models using organoids (from lung and uterus) in relevant large animal models (equine and bovine) by using E. coli and S. aureus (from endometrial and lung infections) modified genetically to stably integrate GFP.
3) To study the effects of MSCs on infection using organoids.
The student will build expertise in stem cell biology, organoid technology, microbiology and infection. He/she will become proficient in a wide variety of cell and molecular biology techniques including bacterial culture and genetic manipulation, MSCs and organoid culture, immunohistochemistry, western blot, enzyme-linked immunosorbent assays, gene expression analyses by next-generation sequencing, qPCR, siRNA and CRISP-Cas9 gene editing. The project brings together the complementary expertise of the co-supervisors in Microbiology and Infection (Prof. David Gally) and Stem Cell Biology and Reproductive Biology (Dr. Esteves and Dr. Donadeu).
References:
1. Cortés-Araya Y, K Amilon, BE Rink, G Black, Z Lisowski, FX Donadeu and CL Esteves. (2018). Comparison of antibacterial and immunological properties of Mesenchymal Stem/Stromal cells from equine Bone Marrow, Endometrium and Adipose tissue. Stem Cells and Development.
2. Rink BE, KR Amilon, CL Esteves, HM French, E Watson, C Aurich and FX Donadeu. (2017). Isolation and characterization of equine endometrial mesenchymal stromal cells. Stem Cell Research & Therapy 8:166.
3. Noel G, NW Baetz, JF Staab, M Donowitz, O Kovbasnjuk, MF Pasetti and NC Zachos. (2017). A primary human macrophage-enteroid co-culture model to investigate mucosal gut physiology and host-pathogen interactions. Scientific Reports 7:45270.
If you wish to apply for this project, please check this link and send your application to this email.
