I've read that once T cells are triggered you get auto immune diseases and once they are triggered, that , my friend,is that!!
What I don't understand is... if you have cancer your T cells are triggered but survivors of cancer go on to live normal lives and don't get autoimmune disease.
So... how can it be that once T cells are triggered that is that?
Anna
oh geesh! YEars ago I studied T cells but am a loss right now...so sorry I am no help at all. But yes, it does have to do with "T" cells if I remember correctly.
When I began researching all that it got really complicated, you have to know the basis of cell structure and then go on to biology and so forth.
I did not have enough time during college to focus on that cause my daughter was just being DX with ADD, so I swithced my concentration over to ADD.....which was VERY TIME CONSUMING!!!!!!!!Hopefully some help will come along to explain.
I think this should be a serious thread. I'm constantly getting confuse with the basics of this disease.
Anybody interested in researching some of this info and posting it? Any beginning cellular biologists out there?
Pip
anna
that's the whole ,000 questions..why don't the T-cells/b-cells turn off once the need is past. At this point that question is not answered by the current level of research.
I'm sure when all is said and done its going to end up being some particular combination of genes, hormones and other body chemistries that keep those cells going when they should be stopping
Ok...I am a science teacher-but I am not sure. Your T cells are part ofhttp://www.ucl.ac.uk/~regfjxe/T.htm
Anna,
Heres something to ponder as we delve into this subject. And a good subject it is. Thank you for starting it.
K.
It's my understanding that each T-cell is programmed to identify a single antigen or type of invader. If you have TB, a certain "killer" cell will attach to it and present it to each T-cell it comes by until one of the T-cells recognizes the TB. The T-cell is then "activated" and then produces TNFs and other immune regulators (cytogens). The activated T-cell also sends the message to the B-cells in the bone marrow to produce an antibody to fight the infection. Therefore, T-cell activation is a must, and I believe is the problem with the virus that causes HIV, which actually attacks the activated T-cells and thus shuts down the whole immune activation system. I think the answer to your question is that once an invader is cleaned out, the immune response to that particular invader is then shut down. With RA, the particular T-cell keeps mistaking the synovium as an invader or the B-cells keep sending out antibodies to attack what is percieved to be an infection, but is only the synovium.
As a side point, those with RA who are infected with HIV will be "cured" of RA because the T-cell activation system is shut down. Some of the biologics (not enbrel and other TNF inhibitors) actually try to mimick this response in a limitted way by inhibiting certain T-cell activation systems (Orencia) or B-cell responses (Rituxan).
Rocckyd, I think B Cells are made from plasma cells not T Cells. To try to answer the initial question about cancer. In cancer The T cell or "cytotoxic" cell (in this case they are called CD8+) works by recognizing surface proteins that are different from the normal cells on the surface of the cancer cell, binding to the the cancer cell, and releasing granzymes, IL, TNF, and lysis factors etc. from it in order to poke holes in the cancer cell and kill it. As far as the normal cell goes, the T cell is turned off because when it binds to the normal cell in the human body it binds through a surface receptor called MHC. This MHC complex cell is present on all normally replicating cells in our body and is used to be able to differentiate self from non-self. Normal cells in the body sends a signal to the T-cell not to attack, whereas in the cancer this signal is not present and the T-cell will lyse it. In HIV the T cell is a different type of cell called a helper cell or a CD4+ cell. The T cell response is considered cytotoxic and cell-mediated because it attacks cancer and intracellular viruses, The B cell response is considered Humoral and extracellular because it produces antibodies, has memory, and attacks extra-cellular pathogens such as bacteria. Sorry for the long post, but I hope it is accurate and helps you to answer your question. With autoimmune diseases, it is important to remember that it is not just activated T-cells at work, but an entire system gone haywire. Macraphages and antibody-producing cells are also big players. Macrophages produces large amounts of the TNF ,IL1, and complement proteins that is seen in RA and many other autoimmune diseases, and may be responsible for a significant amount of inflammation and damage from the disease. I think justtoday is also right on in his post.
Contracting HIV will cure you of RA?
Maybe "cure" isn't the perfect word here - but all the symtpoms will go away and the progressive nature of RA will cease. Once you have no immune system, you can't have an autoimmune disease.According to The New Arthritis Breakthrough by Herny Scammell - there are no reported cases of RA or AIDS. Get one, can't get the other. I've never found run across info that counterdicts that statement.
Pip
isn't our immune system confusing???!!! hee hee"The importance of T cells in RA is underlined by the fact that indivuduals who contract AIDS experience almost complete remission of their arthritis-but at a very high price, of course."
I believe his primary point is that the T cells, specifically the Th1 "helper cells", are often the primary problems with the progression of RA. These T cells, along with macrophages, release the cytokines (TNF, etc) in the synovium, thus causing inflammation and joint destruction. When AIDS search and destroy these "helper" T cells, they will invariably destroy the ability of your body to make these cytokines.
Put simply - No immune system, no autoimmune disease.
Here is a good explanation along with the other cells. This site is pretty