The Impact of Age on Adaptive Immunity in Adults Infected with RSV
Research type
Research Study
Full title
The Impact of Age on Adaptive Immunity in Adults Infected with Respiratory Syncytial Virus
IRAS ID
154109
Contact name
Christopher Chiu
Contact email
Sponsor organisation
Imperial College London Clinical Research Office
Research summary
Research Summary
Respiratory syncytial virus (RSV) is one of the most common causes of chest infection worldwide, with 64 million episodes and 160,000 deaths each year. Despite this, it remains an under appreciated health problem and there are currently no specific treatments or vaccines against it. Although RSV infection is most frequent in young children, the majority of deaths occur in older adults, particularly in those with underlying heart and lung disease. This is believed to be due in part to the aging immune system's reduced ability to protect against infection and symptomatic disease. However, little is known about the way human immune responses to RSV infection in older individuals differ from those of younger people. Further understanding of the mechanisms underlying immunity and potential impairments in these higher-risk people are therefore necessary. This project aims to study the role of T cells (which destroy virus-infected cells and are likely to be essential for recovery from infection) in healthy older volunteers after they have been given an RSV-induced common cold. Samples will be taken from the blood and respiratory tract in order to identify the differences in T cell responses that occur in older adults compared with their younger counterparts. Participants will be carefully screened to ensure they do not have any underlying health problems that might make them more at risk of severe disease and will be monitored closely throughout the course of infection. We anticipate that T cell function even in healthy older individuals will be impaired compared to young adults, thus contributing in those with additional health problems to more severe disease. By analysing the networks of genes that are switched on and off, we aim to identify the particular defects underlying these functional defects in order to ultimately define targets for novel treatments and T cell-stimulating vaccines.
Summary of Results
RSV is a viral infection that can cause serious illness in older adults, especially those who are frail or have heart, lung, or immune system problems. It also often affects young children. To understand why older people might be more vulnerable to this infection, healthy volunteers aged 60-75 were intentionally exposed to RSV in a controlled setting. About two-thirds of them got infected, mostly experiencing mild cold-like symptoms, and none became sicker than expected. We studied how their immune systems responded by looking at factors like white blood cells, antibodies, proteins, and gene activity in the blood, nose, and lungs. When compared to younger adults who were infected in the same way, the older participants developed higher levels of virus, but their symptoms were similar. Along with this, the immune responses in their nose and lungs differed in timing and intensity, although the differences in the blood were less pronounced. These results suggest that aging affects the immune system in different ways locally and systemically, and this knowledge could help in designing better treatments for older people that focus on the respiratory system.
REC name
London - Fulham Research Ethics Committee
REC reference
14/LO/1023
Date of REC Opinion
31 Jul 2014
REC opinion
Further Information Favourable Opinion