How Long Does it Take for "Memory" Immune Cells to Form in Response to a Bacteria?

Wondering how long it takes, from infection, for your immune system to make enough B and T cells to ensure (or at least suggest) long term active memory.

If the question is nonsensical, note that I wondered it after reading this:

(Attributed to Dr. Andrew Weil, but don’t quote me on that. It’s going around Facebook, so it might have been said by a sufficiently verbose marmoset, for all I know.)

Made me wonder if there might be any value in allowing an infection to run a short course, to gain long term immunity, before treating with antibiotics. Or whether that long term memory process begins before or after symptoms appear/antibiotics are administered.

Trying to simplify here… The first time some part of the infection is recognized by any naïve lymphocyte it may take a few days, and then production of the first wave of antibodies start, but those are not as good, as efficient, and are not related to memory. Then, after perhaps closer to one week, enough lymphocytes recognize the infection and are attuned to it, and eventually some of them are set to become various kind of memory cells.

The second time around, it again may take a couple of days for the precise part of the infection to be recognized by the immune system. But once they do recognize it, the response is faster, and it’s already finely attuned against the invader (provided invader hasn’t mutated, natch).

Two things (at least) with the quote you mention:

First, by the time you feel sick, the immune system is already responding, your body is already trying to fight the assault. You know what happens if you do not have a response? Nothing, and then you’d die quick. But if you’re already feeling “ill”, then yea, your body is likely already responding to whatever it is.

Second, you really do not want the immune system to go overboard or to respond too soon, too fast, too strong. You’ll die that way too!

Short thing: The immune response is already working and the memory cells are being created and everything is being set in motion by the time you start feeling sick, for the most part.

Thank you for the response, KarlGrenze, and also thanks for simplifying. I know immunology is an incredibly complex field that I don’t come even close to fully understanding.

So do you think it fair to challenge the quoted line of thinking, because the immune system “becomes stronger” before we ever reach for the antibiotics?

I guess what I mean is…if I have, say, a particular strep infection, and my throat hurts, and I take an antibiotic for it and it goes away…will I titer positive for antibodies to that strep in six months? Will my long term immunity be any “stronger” if I don’t take antibiotics for it, and get better (after being more miserable longer, of course) anyhow?

Hmm… For the specific case of strep, I cannot tell. Certainly, for some diseases, your antibody titers remain strong for years (that is, after all, the desired outcomes for vaccines). It is also important, especially in diseases that are cured more by cell to cell interaction than via antibodies, to keep those memory cells alive (and hell, you need the antibody-producing memory cells too, of course).

(Wait a sec while I have visions of immunology figures and drawings)…

OK, the production of memory cells starts with the recognition of some part of the disease-causing organism (strep, virus, bacteria, fungi, any baddie, etc.). Once that part is recognized by some naïve lymphocyte, in the presence of the correct mileu of molecules and cell interactions, that lymphocyte is activated and starts producing/responding accordingly. The fight is on for that branch of the immune system. Mind you, this is likely before you have been prescribed anything, or at most, close to that time.

Now, lymphocytes are the adaptive branch of the immune response. They adapt and they have memory. This means that, once some part of the baddie is identified, the cells that can identify that part:

  1. Reproduce like crazy, man.

  2. Start deploying all sorts of weapons, like antibodies and other molecules.

  3. To better recognize the enemy, they fine-tune their detection system. They become able to better recogize it. This also requires lots of cell interaction and the correct environment. That’s why they also respond quicker the second time around, they have become better at it (of course, the enemy also usually improves).

  4. To recogize the enemy later on, they also start producing memory cells. Again, depending on the environment and location, some of those lymphocytes become memory cells. And really, there are quite a few types of memory cells. Some are short-term memory cells, some are long term, some remember some things, some remember others. Shudders It is at the same time a fascinating and complex area of research.

  5. They also fine tune their weapons. Those first wimpy antibodies are not the same as the antibodies produce later, which are better and more efficient. Also, the cells that produce them become more specialized (little antibody factories).

I think my take is that, if you go by “at the first sign of infection”:

  1. Once you notice you’re sick, your immune system is activated, cells are being recruited, most likely memory cells are already activated.

  2. Antibiotics are not, for the most part, a one shot cure. It’s more like assisting the body by reducing the numbers of enemies they have to deal with, but the immune system still has to eliminate them and clean up after the dead enemy.

  3. Yea, you may be able to sometimes skip antibiotics, just you will feel miserable for longer… BUT:

  4. Some diseases can go quickly from “able to be destroyed by the immune system” to “immune system loses, owner of said immune system also loses”.

  5. Chronicity brings its own set of problems. In some cases, you really do not want that organ or body part to be a war zone for too long. Better on the long term to cut the fight short with the aid of meds.

Again, thank you, thank you!

I think, given this explanation, I’m comfortable with explaining to people who ask that their immune system is still going to “get a workout” and make antibodies even when they take the antibiotics. It is a very simplified explanation, but it sounds essentially correct.

One thing to keep in mind too is that, depending on the disease, antibodies may not be the way to combat it. :wink: They are but one part in one of the branches of the immune system. For many diseases the body has determined (for better or worse) that antibodies are not the best way to combad them. So some disease responses do not rely on them that much.

But yea, in an otherwise healthy individual, for the simple and most common purpose, if there is a sign of infection, the immune system is getting a workout.

Thank you. Good thing this was not need answer fast.

gasp … Are you implying that something Andrew Weil said wasn’t 100% accurate?! :eek:

This is worth quoting for truth. The 1917-18 influenza epidemic killed mostly healthy adults with excellent immune systems for this reason. It provoked an overreaction (Cytokine storm) and that is what killed most of the people that ended up dying. A lot of the victims were strapping young men who had been recruited to fight in WW1.

A similar thing occurs with Toxic Shock Syndrome (IIRC) and a few other diseases, the molecule that is recognized by the immune system is also able to activate them easier than it should, bypassing the immune system’s checkpoints, stops, and counterbalances.