Memory T cells reside in bone marrow

When memory T cells form, where do they "hang out" until needed at a later time?  Scientists have debated this for some time.

Recent evidence recently published in the journal Immunity suggests an answer . . .

memory T cells prefer to reside in the bone marrow.

Until now, most immunologists believed that these cells circulate in the bloodstream.  So this is somewhat of a game-changer.  To me, this makes a lot more sense.  It seems that tucking memory cells away in the bone marrow conserves them more efficiently than free circulation would.

Here is a great article summarizing the discovery and its importance:

Home of immune memory found
Edyta Zielinska
The Scientist (NewsBlog) 7th May 2009

Here's a link to the original research article:

Professional Memory CD4+ T Lymphocytes Preferentially Reside and Rest in the Bone Marrow
Koji Tokoyoda, et al.
Immunity  07 May 2009

Click here for a FREE image showing red bone marrow in a fresh dissection of the humeral head . . . you can use it in a PowerPoint slide or in your syllabus or class notes.