MRI of brain immune cells
Research type
Research Study
Full title
Development of a diffusion MRI imaging technique sensitive to changes in microglial morphometry
IRAS ID
206920
Contact name
Neil A Harrison
Contact email
Sponsor organisation
Cardiff University
Duration of Study in the UK
3 years, 0 months, 0 days
Research summary
Depression is a psychiatric condition in which patients feel persistently sad and hopeless. It interferes with activities of daily life, and can be profoundly disabling. Unfortunately, one third of patients with depression fail to improve even with the best currently available treatments.
There is increasing evidence that the immune system, the system dedicated to fighting infections in our body, is in a state of ‘hyperactivity’ in some patients with depression. This ‘hyperactivity’ (also called inflammation) acts as if patients were fighting an infective agent, even though they do not have an on-going infection. Recently, we have also discovered that this inflammation can affect the brain and cause activation of brain immune cells known as microglia.
Currently, the only way to image microglia is with a type of brain imaging called positron emission tomography (PET) imaging. However, this technique is extremely expensive. It also involves the use of radiation and is very difficult to analyse which limits its usefulness as a clinical investigation.
This project aims to develop a new technique for imaging microglia using magnetic resonance imaging (MRI) which is widely available in all major hospitals. To do this we will use a special type of MRI technique called ‘diffusion imaging’ before and after activation of the immune system. We will activate the immune system by giving healthy volunteers a substance called lipopolysaccharide (LPS for short) which simulates the presence of an infection. This causes the body to activate the immune system even though no infection is actually present. It is safe and has been used in thousands of participants worldwide.
If successful, this project will provide a new tool for imaging effects of inflammation on the brain. This development would be of considerable value for monitoring response to novel antidepressant treatments targeting the immune system.
REC name
London - Queen Square Research Ethics Committee
REC reference
17/LO/0485
Date of REC Opinion
23 May 2017
REC opinion
Further Information Favourable Opinion