Immunotherapy, also known as biologic therapy, is a type of treatment that helps the body's natural defences fight disease and infection. It improves or restores immune system function by using substances made by the body or in a laboratory. Our immune system aids in the fight against infections and diseases. It is made up of white blood cells as well as lymphatic organs and tissues.
- Our immune system is made up of organs, special cells, and substances that work together to protect us from infections and other diseases.
- Immune cells and substances travel through our bodies to protect us from infection-causing germs.
- The immune system monitors all of the substances that are normally found in the body. Any new substance that the immune system does not recognise sets off an alarm, prompting the immune system to launch an attack. Germs, for example, contain substances that are not normally found in the human body, such as certain proteins.
- The immune system recognises these as "foreign" and responds by attacking them. The immune response can destroy anything containing the foreign substance, such as germs or cancer cells.
- They can also help us fight cancer in some ways.
- However, the immune system's ability to fight cancer on its own is limited.
- Because cancer cells aren't sufficiently different from normal cells, the immune system doesn't always recognise them as foreign.
- The immune system may recognise cancer cells in some cases, but the response may not be strong enough to eradicate the cancer.
- Cancer cells can emit substances that prevent the immune system from detecting and attacking them. Immunotherapy is required to combat this.
- Immunotherapy has piqued the interest of researchers, clinicians, and pharmaceutical companies in recent years, owing to its potential to treat a variety of cancers.
- Immunotherapy aims to assist the immune system in recognising and attacking cancer.
- Rather than attacking the disease directly, as chemotherapy does in cancer, immunotherapy attempts to enlist the patient's own immune system in the fight.
- The immune system is a web of cells, tissues, and biochemicals secreted by them. It protects the body from viruses, bacteria, and other foreign invaders.
- Immunotherapy is a type of treatment that uses drugs to allow immune cells to fight cancer. These drugs interfere with a mechanism known as checkpoint. Cancer uses checkpoint to shut down the immune system.
- T-cells are deactivated by tumour cells binding to them. Tumor cells can deactivate T-cells, but immunotherapy drugs can prevent this.
APPLICATIONS OF IMMUNOTHERAPY:
- Recent use of immunotherapy in the treatment of AIDS: Scientists used two widely used anti-HIV antibodies that were injected into a test animal, a monkey, after it had been infected with a virus that was similar to HIV. In response to these anti-biotics, monkeys demonstrated improved immunity to the virus over a longer period of time.
- New immunotherapy breakthroughs have ushered in a new era in cancer treatment. Immunotherapy appears to be a promising new cancer treatment strategy. It has fewer side effects than chemotherapy and may be able to control tumour growth.
- Immune enhancement therapy is a subset of immunotherapy. Natural killer cells and other relevant immune cells from a person's own peripheral blood are expanded in vitro and then re-infused in autologous immune enhancement therapy.
- Hepatitis C and Chronic Fatigue Syndrome have been tested with the therapy.
- Suppression immunotherapy’s: Immune suppression dampens an abnormal immune response in auto-immune diseases or reduces a normal immune response to prevent rejection of transplanted organs or cells.
- Immunosuppressive medications aid in the management of organ transplantation and autoimmunity. Proliferation of lymphocytes is required for immune responses.
- Immune tolerance therapies aim to retrain the immune system so that it no longer attacks its own organs or cells in the case of autoimmune disease, or accepts foreign tissue in the case of organ transplantation.
- Allergies are treated with immunotherapy. While allergy medications (such as antihistamines or corticosteroids) treat the symptoms of allergies, immunotherapy can reduce sensitivity to allergens and thus reduce the severity of allergies.
SERIOUS SIDE EFFECTS
- All patients should be aware of some potentially life-threatening side effects of immunotherapy. High blood pressure, bleeding, blood clots, kidney damage, severe rashes, and other serious side effects have all been linked to monoclonal antibodies.
- CAR T-cell therapy can also result in cytokine release syndrome (CRS). High fevers and low blood pressure are common symptoms of CRS. Seizures, confusion, serious infections, low blood cell counts, and severe headaches are all possible side effects.
TYPES OF CANCER IMMUNOTHERAPY
- Checkpoint inhibitors: These drugs work by removing the immune system's "brakes," allowing it to recognise and attack cancer cells.
- T-cell therapy with chimeric antigen receptors (CAR): This therapy takes T-cells from a patient's blood, mixes them with a special virus that teaches the T-cells how to attach to tumour cells, and then returns the cells to the patient so they can find, attach to, and kill the cancer.
- Cytokines: This treatment stimulates immune cells to attack cancer by using cytokines (small proteins that carry messages between cells).
- Immunomodulators are a class of drugs that boost certain parts of the immune system in order to treat cancer.
- Vaccines for cancer: Vaccines are substances that are injected into the body to trigger an immune response to certain diseases. We usually think of them as something that is given to healthy people to help them avoid getting sick. However, some vaccines can aid in the prevention or treatment of cancer.
- Man-made versions of immune system proteins are known as monoclonal antibodies (mAbs or MoAbs). Because they can be designed to attack a very specific part of a cancer cell, mAbs can be very useful in cancer treatment.
- Oncolytic viruses are viruses that have been genetically modified in the lab to infect and kill tumour cells.
- Tregs, or regulatory T cells, are immune system brakes that keep our immune system from becoming overactive. Tregs are frequently found in large numbers in tumors, preventing other immune cells from eradicating the disease.
- CD25: A protein called CD25, which is abundant on the surface of Treg immune cells, is a distinguishing feature.
EVOLUTION OF IMMUNOTHERAPY
- Multiple anecdotal reports of tumours disappearing spontaneously or after an infection with concomitant high fever have been reported from ancient Egypt to the early nineteenth century.
- Galen, a Greek physician, was the first to describe the similarities between cancer and inflammation, noting that cancer could develop from inflammatory lesions.
- Two German physicians, Fehleisen and Busch, are credited with the first scientific attempts to modulate patients' immune systems in order to cure cancer. Both noticed significant tumour regression after erysipelas infection. They both described their observations and attempted to replicate them later, but to no avail. Fehleisen eventually identified the bacterial strain that was causing the erysipelas and tumour shrinkage as Streptococcus pyogenes.
- William Bradley Coley, dubbed the "Father of Immunotherapy," took the next significant step. In 1891, Coley was the first to try to use the immune system to treat bone cancer. For over fifty years, his accomplishments went largely unnoticed, despite several seminal discoveries in the field of immunology, such as the discovery of T cells and their critical role in immunity in 1967.
- Finally, in the 1980s, the field of immunotherapy re-emerged when the first vaccine based on a single cell surface antigen became available in the form of a hepatitis B vaccine (1). Optimism that immunotherapy could be used to treat a variety of diseases, including cancer, resurfaced, propelling research to where it is now.
In 2018, the Nobel Prize was awarded to James Allison and Tasuku Honjo for their meticulous work on checkpoint molecules as potential therapeutic targets. That work has resulted in the successful development of new checkpoint inhibitors, CAR T-cells, and oncolytic viruses, and the rapid pace of such progress provides the best hope for cancer treatment in the future.