Altered Leucocyte Function in Normal Ageing (ALFNA)

Summary

When we are infected with bugs such as the ‘flu virus’, our immune system activates a number of mechanisms. The aim is to both clear the bug as quickly as possible, but also prevent us becoming infected in future. The immune system produces a number of white blood cells that can recognise the bug if it is seen again, and set up a much more rapid response to clear the bug before the infection takes hold. One of the best ways our immune system has of doing this is to produce antibodies, small proteins that recognise the bug and stick to the surface of the bug itself, or the cell of the body that is infected by it, and ‘flag-up’ the infection to the other white blood cells. This means that infections are recognised more rapidly and therefore the immune response to infection begins much more quickly.

We exploit this system of producing antibodies through vaccination. Vaccination works by introducing the immune system to the bug, altered so it cannot cause an infection, or just a key part of it. This stimulates the immune system to produce antibodies. This means that if the immune system is exposed to the bug at a later date, it can recognise it before it has time to produce the full-blown disease. The body either clears the bug completely without showing signs of infection, or the symptoms are milder.

As we get older, the system we have for recognising bugs and producing antibodies becomes weaker. and for this reason older people are routinely vaccinated to boost the immune system and try to prevent severe infections (for example the annual flu vaccination). Unfortunately this is not always successful and it is not clear which parts of the immune system are responding poorly to the vaccination.

In this study, we are interested in looking at the white blood cells that are involved in producing the antibodies. We are also interested in understanding how our white blood cells change with age, and what these changes mean for the response to vaccination. This will allow us to see if we can identify a particular change in these cells that might lead to this poor response, potentially allowing us to change the way we design vaccines to improve vaccine responses in older people.

Participation: For this study we recruited 69 healthy volunteers from the Cambridge BioResource to attend three appointments. At the first appointment they had the seasonal flu vaccine and gave a 50ml blood sample. Two further blood samples were given 7 and 42 days after the first visit. Study visits were run by the Cambridge BioResource team.

Organisation: This study is organised by Dr Michelle Linterman at the Babraham Institute. 

Publication: Human blood Tfr cells are indicators of ongoing humoral activity not fully licensed with suppressive function