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Oh wow, now we are really getting into the nitty-gritty - what a fantastic video - the immune system is so incredibly complex, thanks for sharing your understanding, more shady things please! My question is why don't the Tc cells do a very good job in cancer?
David, this is a very good question and I believe (in my logic) that the T cell can only do so much because T cell lymphocytes are not as plentiful in the body as say, neutrophils and T cells are called into battle way to late for it to overpower a mass of cancer cells. When a protein from a cancer is presented as shown in this video, the first defenses that come to the aid of the human body is the neutrophils and the body eventually gets bogged down by an overload of dying white blood cells. In the case of cancer, the wbc count skyrockets, and many people develop fevers and feel flu like symptoms and eventually this is what sends them to the doctors for a check up. T lymphocytes only make up about 20-40% of our wbc count and Eosinophils (1%-4% of all WBCs). There is some very exciting news however in the field of immunology however that may have found a potential cure for acute lymphoblastic leukemia (ALL)! If you read medical journals you hopefully came across a little girl named Emily Whitehead who was the first pediatric patient to receive an experimental T-cell therapy in April 2012.She was near death when they decided to give her an experimental treatment. She has been in remission since May 2012. What was most fascinating about this therapy was, she and a handful of other patients each had millions of T-cells removed. Using the disabled form of HIV, these were modified to attack cancer cells before being put back into their systems. So far, only Emily and two other adults have responded with complete remission, but this helps immunologists and oncologists think outside the box and gives them different avenues to venture! Truly exciting!
gw197234 wouldnt it be somehow possible to dope the abilities of t-cells or the concentration of them in our system? has anyone tried to do something like that?
+gagahami great questions. I'd also like to know if something like this can be done. The only reason, I've learned, that this might not be possible is because the body heavily regulates the availability of these immune cells. For example, they don't need such a high concentration of T cells, so even if we did somehow inject or duplicate them at a higher rate, other homeostatic regulations might reduce the amount anyway. So, we might have to design a method to retain these T-cells also. Also, the lifespan of CD8+ T cells aren't as long :(.
How does the B Lymphocyte "engulf" the pathogen? Is there some type of invagination like a phagocyte? Also, when it gets engulfed, does it just hang out in the cytoplasm or is there something like a phagozome to wait in before attaching to an MHC2? By the way, what does the "+" sign in CD4+ and CD8+ stand for?
Hey hey, in English subtitles somewhere around 7:26 it says "molecules like preference" instead of "perforins". I know it's been a while since the video was published but if you could correct it it'd be great :)
i have a doubt...this cell thts been infected like mentioned...fr eg: if hiv has infected a cell (in fact the first cell infected by it)...these cells recognize themselves that they are infected and then produce mhc1 complexed with the hiv antigen and present it on the surface... but for a cytotoxic t cell which has never encountered the antigen thats presented by this mhc 1,how can it hav recptors to bind...? like if it was the frst cancer cell too...how do they recognize it in the first place?
I dont understand cancer cells: can cientist take a piece of cancer (with MHC1), then get a CD8 cytotoxic cell from the patient which then make memory and effector cells?. Then get them to replicate a lot and infuse them back to a cancer patient (or inject directly on the tumor). Does that not destroy the cancer entirely for cure?
