Memory Cells

Beyond my intellectual horizens, entire fields of knowledge have been cleared, sown, and made productive.

In trying to learn more about what Zinkernagel has accomplished, I focused a websearch on "immunological memory" and uncovered something called a "memory cell."

I don't recall learning about those in college biology, and most of what I've picked up since then comes from Ozzy and Drix.

Fortunately, memory cells do their work despite my ignorance, memory lapses, and lack of seriousness. Here's what Wikipedia tells me about a type of memory cells called "memory B cells":

"Memory B cells are B cells that although activated by the immune system . . . are stored inside the circulatory system for later use, for long periods of time, possibly a whole lifetime. Like other cells such as helper T cells, killer T cells, and plasma cells[,] they never become directly involved in the immune response to foreign objects in a living body. If a pathogen [that] the body has already encountered invades, memory B cells can recognize the pathogen and start to divide. Quickly, they form a new generation of cells, and memory cells. The new generation kills off the pathogen so quickly [that] the body does not become noticeably ill."

I'm not sure what this wiki means when it says that "they form a new generation of cells, and memory cells." Possibly, this is badly edited, which happens with Wikipedia since it's the product of a multitude of hands (to which I've now added my own). My first guess is that it means that "they form a new generation of memory B cells." Yet if "they never become directly involved in the immune response to foreign objects in a living body," then it would have to mean something like "they form a new generation of antibodies to fight the pathogen, and new memory B cells are also formed." But I'm really only guessing, so don't take this as gospel.

Also, memory B cells are only one kind. There are also "memory T cells," about which, Wikipedia has nothing to say . . . except:

"Wikipedia does not yet have a page called Memory T cells."

Thanks for letting us know.

But a dead end is never the end. Just re-Google. I did and found this nice layman-friendly page by Peter Stevenson, who likes to use hyphens in telling me:

"There are two types of immune response: cell-mediated (CMI) associated with specialised blood cells called T-cells, and antibody mediated associated with specialised blood cells called B-cells. Both immune responses act on substances called antigens."

Belonging to the T-cell sort are:

"Memory T-cells -- which recognise the original invading antigen. When the antigen returns thousands of memory cells are available to initiate a far swifter reaction than occurred during the first invasion."

Got it. Now for those B-cells:

"B-cells that are activated but do not differentiate into plasma cells remain as memory B-cells, ready to respond more rapidly and forcefully should the same antigen reappear at a future time."

This helpful little article also informs us that whereas the T-cells move around throughout the body, B-cells stay put.

I guess that I'm more peripatetic T-cell than homebody B-cell myself, being a Gypsy Scholar and all, and as a historian, part of my job is to remember the past and prepare for the future.

Else what's a memory for?