Is there always a presence of activated T cells in a healthy host? - (Dec/18/2014 )
I understand that after and immunogenic response, you get T cell activation (marked by CD69 and CD25 expression), and that activated T cell numbers contract after a while. My question is that if you were to pull blood from a healthy individual and not include CD25+ Tregs in your analysis, would you expect to see CD25+ or CD69+ activated T cells?
Not being an immunologist, I may be completely wrong here:
My thoughts are - yes, you should. The body is constantly under assault by all sorts of antigens (e.g. in the gut and nasal passages), so there should be a small population of activated T cells all the time.