Emily Whitehead, an American girl, was diagnosed with a leukemia kind in 2010 that is typically fatal. That time she was only five years old. After two years, she was the first pediatric patient to be given the opportunity to receive CAR-T treatment, which reprogrammes the immune system to target malignant cells. The therapy was effective. “Of Medicine and Miracles,” a documentary film, was released in 2022 and chronicled her journey.
The second of those m-words is not one that researchers employ lightly. However, the excitement seems justified by CAR-T therapy. Ten years after Emily’s therapy began, supporters of the approach are discovering that the cells causing a variety of other illnesses, such as heart problems and asthma, have features in common with cancer cells that may make them targets for similar therapies. Clinical trial results thus far seem promising.
The reason CAR-T treatment is effective is that the surface of many cancerous cells contains unique protein markers known as antigens. Immune system T-cells from a patient are removed, genetically modified to produce “chimeric antigen receptors” (the CAR in CAR-T) that recognize these antigens, and then the patient’s body is given back the altered T-cells. For example, a number of CAR-T cell therapies approved for the treatment of lymphoma and leukemia make use of T-cells modified with CARs that are able to recognize the protein CD19, which is present on the exterior of those cancer cells.
Scientists now believe that this form of treatment is also effective for other forms of diseases as well. Consider asthma. Every day in Britain, three individuals are killed by severe asthma attacks, despite the fact that millions of people are able to control their symptoms thanks to medications. This is frequently caused by an immune system that isn’t working properly, which sets off an inflammation response known as type 2. Eosinophils, which are hostile white blood cells released by the body as a defense against parasites, can irritate the airways and make it difficult for those with severe asthma to breathe.
The goal of asthma medications such as injectable antibodies and inhaled steroids is to decrease the amount of eosinophils in the blood, which in turn reduces inflammation and symptoms. It has now been demonstrated by Chinese researchers that CAR-T cells can be modified to perform better, at least in mice. They detailed how a single injection of the cells into rats designed to imitate the symptoms of asthma effectively cured the animals of the illness in a study published in May in Nature Immunology.
Some claim that CAR-T cells can even target aging itself, eliminating cells that have experienced a functional decline associated with aging. Analogous processes known as senolysis have been demonstrated to be effective in treating a variety of age-related chronic illnesses, such as cancer and liver impairment. Significantly for CAR-T therapy, researchers have identified an antigen: urokinase plasminogen activator receptor (uPAR) is a protein that many aging cells express in greater amounts. Researchers in the United States demonstrated that CAR-T cells designed to attach to uPAR might increase senolysis, with a range of benefits including enhanced metabolism and exercise ability, in a study published in January in Nature Aging. The researchers again used mice in their research.
Source: Economist
