Effect of inhaled GM-CSF on human alveolar macrophage function
Research type
Research Study
Full title
INhaled Sargramostim In Groups of Healthy and inTensive care unit participants to study Alveolar Macrophage function - a clinical trial (INSIGHT-AM trial)
IRAS ID
319303
Contact name
John Simpson
Contact email
Sponsor organisation
Newcastle upon Tyne Hospitals NHS Foundation Trust
ISRCTN Number
ISRCTN78203402
Duration of Study in the UK
2 years, 11 months, 30 days
Research summary
Human lungs contain specialised cells (alveolar macrophages, AMs) that detect germs. In mice AM function depends on a molecule called GM-CSF. How GM-CSF influences human AM function is poorly understood. Older people and critically ill patients are at increased risk of pneumonia, potentially because their AMs function less well. It is therefore possible that inhaled GM-CSF could boost AM function and prevent pneumonia in people at high risk.
Twenty healthy young people who answer an advert and provide informed, written consent will inhale GM-CSF or a “dummy” treatment (placebo) on two consecutive days. Neither the participant nor the research team will know which has been inhaled. On the third day the participant’s lungs will be “washed” in hospital to retrieve AMs. These will be taken to a laboratory where their capacity to kill bacteria will be tested, with identification of molecules involved in these processes. After at least a month, participants will repeat this process, except if they inhaled GM-CSF last time they will inhale placebo next time (and vice versa).
Twenty healthy older people will complete exactly the same procedures described above.
Twenty critically ill patients will receive inhaled GM-CSF or placebo on two days and have their lungs washed on the third (i.e. they will undergo the procedures once only). Finally, we wish to determine whether laboratory-derived AM-like cells can faithfully mimic human AM function (if they can we could avoid washing peoples’ lungs to get AMs in future) – therefore, twenty healthy people will have a lung wash with no inhalation procedures and we shall compare function in AMs and AM-like cells.
The study will provide entirely novel information about human AM function. A beneficial, safe role for inhaled GM-CSF may suggest future trials assessing whether this treatment can safely prevent pneumonia in patients at highest risk.
REC name
Wales REC 6
REC reference
23/WA/0298
Date of REC Opinion
25 Oct 2023
REC opinion
Favourable Opinion