Memory B/T cells

[biophysics]

I've learned about memory B and T cells. I'm wondering how many of each a person has for a specific antigen? How long do they live?

[Monique]

I don't know the exact numbers, but when you look at tetanus vaccinations you need to get a booster after 10 years. So they can live up to ten years.

Here a study who looked at it in detail: http://www.jimmunol.org/cgi/content/full/171/10/4969#F1
In this study, we demonstrate that smallpox vaccine-specific memory B cells last for >50 years in immunized individuals. Virus-specific memory B cells initially declined postimmunization, but then reached a plateau 10-fold lower than peak and were stably maintained for >50 years after vaccination at a frequency of 0.1% of total circulating IgG+ B cells. These persisting memory B cells were functional and able to mount a robust anamnestic Ab response upon revaccination.