Your immune system keeps track of all the chemicals that are naturally present in your body. Any new chemical that the immune system does not identify sets up an alert, prompting the immune system to launch an attack.
Chimeric antigen receptor (CAR) T-cell therapy is a method of modifying immune cells called T cells (a kind of white blood cell) in the lab so that they can locate and destroy cancer cells. Because it includes changing the genes inside T cells to help them target cancer, CAR T-cell therapy is frequently referred to as a form of cell-based gene therapy.
Even when other therapies are no longer effective, this sort of therapy can be highly beneficial in curing some types of cancer.
Antigens and immunological receptors have a similar connection to a lock and key. Each foreign antigen has a unique immune receptor that may connect to it, similar to how a lock can only be opened with the appropriate key.
Antigens are found on cancer cells as well, but if your immune cells lack the appropriate receptors, they won’t be able to connect to the antigens and help eliminate the cancer cells.
Antigen receptors with chimeric antigens (CARs)
T cells are collected from the patient’s blood and genetically modified in the lab by adding a gene for a man-made receptor (called a chimeric antigen receptor or CAR). This aids in the identification of particular cancer cell antigens. After that, the CAR T cells are returned to the patient.
Because various tumours have distinct antigens, each CAR is tailored to the antigen of a given malignancy. The cancer cells in certain types of leukaemia and lymphoma, for example, carry an antigen called CD19. CAR T-cell treatments for certain malignancies are designed to bind to the CD19 antigen and will not work if the CD19 antigen is missing.
CAR T-cell treatment is a type of immunotherapy that uses a patient’s own cells to
CAR T-cell treatment might take many weeks to complete.
The T cells are being collected.
A process called leukapheresis is used to extract white blood cells (which contain T cells) from the patient’s blood. Patients generally lie in bed or recline in a reclining chair during this treatment.
During the operation, the patient must remain sitting or laying down for 2 to 3 hours. During leukapheresis, calcium levels in the blood might decrease, causing numbness, tingling, and muscular spasms. This is readily addressed by replenishing the calcium, which may be done either orally or intravenously.
CAR T cell production
T cells are isolated, transferred to the lab, and changed by adding the gene for the particular chimeric antigen receptor after the white cells have been removed (CAR). As a result, they are known as CAR T cells. In the lab, these cells are then cultivated and multiplied. The enormous number of CAR T cells required for this treatment can take many weeks to produce.
Getting a CAR T-cell injection
Chimeric antigen receptor T cells will be returned to the patient after enough have been created. The patient may be given chemotherapy a few days before the CAR T-cell injection to assist reduce the amount of other immune cells. This increases the chances of CAR T cells being activated and fighting cancer. Because CAR T cells operate best when there are cancer cells to target, this chemotherapy is typically not particularly powerful. When CAR T cells attach to cancer cells, their numbers grow, allowing them to help eliminate even more cancer cells.
CAR T-cell treatments that have been approved
The FDA has authorised CAR T-cell treatments to treat certain lymphomas and leukemias, as well as multiple myeloma. CAR T-cell therapy is usually utilised after other options have been exhausted.
CAR T-cell treatments that have been authorised thus far include:
Tisagenlecleucel, commonly known as tisa-cel, is a kind of stem cell (Kymriah)
Axicabtagene ciloleucel, or axi-cel, is a kind of axicabtagene ciloleucel (Yescarta)
Brexucabtagene autoleucel, commonly known as brexu-cel, is a kind of brexucabtagene autoleucel (Tecartus)
Lisocabtagene maraleucel, commonly known as liso-cel, is a kind of lisocabtagene maraleucel (Breyanzi)
Idecabtagene vicleucel, commonly known as ide-cel, is a kind of idecabtagene vicleucel (Abecma)
Possible adverse effects of Chimeric antigen receptor T-cell treatment
Chimeric antigen receptor T-cell treatment can be highly effective against certain types of difficult-to-treat malignancies, but it can also have significant or even fatal adverse effects. As a result, it must be administered at a medical facility that is particularly skilled in its usage, and patients must be continuously monitored for many weeks after receiving CAR T cells.
CAR T cells may produce huge amounts of molecules called cytokines into the bloodstream as they grow, which can stimulate the immune system. The following are serious adverse effects that may occur as a result of this release:
- Chills with a high temperature
- Breathing problems
- Symptoms include severe nausea, vomiting, and/or diarrhea
- Dizziness or lightheadedness Headaches
- a rapid pulse
- I’m really weary.
- Pain in the muscles and/or joints
- Doctors are learning how to detect CRS early and how to treat it as they acquire more expertise with CAR T-cell treatment.
- Nervous system issues: This therapy can have significant side effects on the nervous system, resulting in symptoms like:
- Consciousness changes
- Irritability or befuddlement
- Twitching or shaking (tremors)
- Speaking and comprehending difficulties
- Loss of equilibrium
- Adult patients are generally advised not to drive, operate heavy machinery, or engage in any other potentially risky activities for at least several weeks after receiving therapy due to the likelihood of these adverse effects.
- Other dangerous side effects include: Other potentially significant CAR T-cell treatment adverse effects include:
- During the infusion, allergic reactions may occur.
- Mineral levels in the blood that are abnormally low, such as potassium, sodium, or phosphorous levels
- A weaker immune system means you’re more likely to become sick.
- Low blood cell counts can lead to infections, tiredness, and bruising or bleeding, all of which can be dangerous.