Blog #8

T cell therapy is a treatment that is intended to allow the body to detect harmful cells in the body and identify them for destruction by the immune system. This is achieved by genetically altering T cells into CAR T cells and growing them in large numbers outside of a human host. These are then injected into the patient. This therapy is used in cancer treatment and specifically in the articles discussed in this blog, leukemia, which is cancer of the blood. The CAR cells mimic T cells and send signals in the body that provoke a similar response. This method of treatment has shown an large response rate from patients and has proven to be very effective in destroying cancerous cells. However, this treatment is not completely effective in curing leukemia. One article discusses some of the drawbacks of the treatment. One of the main issues is that upon relapse of the disease, the CAR cells are no longer effective against the new cancer cells because the cancer cells do not present the correct antigen. This same study set out to find the best way to alter this therapy to make it more effective against a wider variety of antigens in antigen presenting cells. By the end of the study they managed to find a CAR T cell to be effective against a larger variety of antigens while also being as least toxic as possible to the patient.

Another study examines many other issues presenting this type of therapy. One of those issues is making the CAR T cells specific enough to only target cancerous cells while also making them general enough to target a wide variety of cancerous cells. The article does emphasize that this therapy is a breakthrough in cancer treatment and has improved the life expectancy and the survival rate for those with leukemia. Down regulation to the CAR T cells is also a concern. Down regulation is when a receptor becomes less sensitive to a substance that binds to it because there is so much of that substance there. A natural example of this in the human body is a negative feedback loop. When enough of a neurotransmitter or hormone binds to a receptor the production of that substance is ceased. With my understanding of the article (which could be wrong) when this occurs during T cell therapy the body will stop supporting and sending the CAR T cells to the cancerous cells, which stops the killing of the cells before all the antigen presenting cells can be destroyed, and therefore causing the cancer to return.

While this therapy has a large success rate in the killing of cancerous cells there are still some problems facing patients who choose to go through this therapy. The major on is that the therapy can cause other diseases and side effects because it leaves the patient immunocompromised. One disease caused by this therapy is cytokine release syndrome which causes flu-like symptoms. This being said, I think that this an amazing break through in cancer treatment. I think it is amazing to use this as an alternative to chemotherapy because T cell therapy uses natural responses in the body to kill mostly harmful cells while chemotherapy kills both harmful and healthy cells in the body. I like this treatment because it feels more natural to the body rather than invading the body with harmful rays and substances. T cells are very familiar to the body and even though it can cause side effects for the patient that are uncomfortable, it is better than some of the side effects for chemotherapy. Overall, I am hopeful for this method of treatment for cancer and I hope of see advances into different types of cancer.