Leishmania mexicana induced perturbations of macrophage metabolism

Rattigan, Kevin Michael (2017) Leishmania mexicana induced perturbations of macrophage metabolism. PhD thesis, University of Glasgow.

Abstract

The interaction between the Leishmania parasite and the macrophage is a bidirectional one of which the outcome of is important for determining if disease progresses or regresses. The parasite is able to modulate the host cell at epigenetic, transcript and metabolic levels. In the context of the latter, immune metabolism is a rapidly growing area of research, and its importance in the context of normal immune function and pathology is increasingly being recognised.
In this thesis a robust, untargeted metabolomics protocol has been developed in order to profile a classical in vitro model of immune metabolism, the inflammatory M1 macrophage. While previous studies use single or multiple M1 stimuli without dissecting their importance, a combinatorial approach is used here to dissect the contribution and interaction of two key M1 stimuli, interferon γ (IFNγ) and LPS. An obvious stimulus-specific response is obvious in our data.
We next used this untargeted metabolomics protocol in parallel with RNAseq to examine the cost of hosting a parasite to the macrophages metabolic and transcriptional profile. By using a heat-killed control it was possible to differentiate between general immune responses and response specific to the live parasite. Additionally, a FACS protocol coupled to untargeted metabolomics was used in order to focus on the infected cell. Furthermore, the inclusion of the above mentioned M1 control revealed that either live or heat-killed Leishmania failed to elicit as strong a response. Finally, stable isotope labelled metabolomics was used to validate key findings.
In summary, our untargeted metabolomics protocol has revealed immune- metabolic perturbations that are induced by IFNγ and LPS or their interaction. This information should be considered if targeting these pathways in a therapeutic context. Furthermore, by using an integrated metabolic- transcriptomics profiling approach, perturbations in glycerol-phospholipid metabolism, central carbon metabolism and arginine metabolism were found. Using stable isotope labelled metabolomics (U13C-Arginine) the current study has given unprecedented insight into how the parasite utilises this crucial amino acid, as well as confirm novel pathways.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Keywords: Leishmania mexicana, macrophage, metabolism, immunology.
• Subjects: Q Science > QR Microbiology
• Colleges/Schools: College of Medical Veterinary and Life Sciences > School of Infection & Immunity > Parasitology
• Funder's Name: Wellcome Trust (WELLCOME)
• Supervisor's Name: Barrett, Professor Michael and Goodyear, Dr. Carl
• Date of Award: 2017
• Depositing User: Mr KEVIN RATTIGAN
• Unique ID: glathesis:2017-8060
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 07 Apr 2017 11:36
• Last Modified: 02 Apr 2019 08:57
• URI: https://theses.gla.ac.uk/id/eprint/8060