By Rachel Fairbank, Texas Health Journalism Fellow
How the immunology revolution is reshaping our understanding and treatment of cancer, aging, long Covid and beyond
The immune system has long been considered a defender against microbes and viruses, with its dysfunction leading to either autoimmune or inflammatory disorders. However, during an HJ24 panel last month, Miriam Merad, an immunologist at the Icahn School of Medicine at Mount Sinai in New York, explained that the immune system plays a much larger role in maintaining our health than expected.
And there are numerous novel opportunities for treatments for cancers, aging, long COVID and many other conditions, she added. “The immune system is in fact, contributing to or shaping all diseases.”
How the immune system has evolved
The immune system, which infiltrates all the organs of the body, has evolved to respond to threats in the body. This evolution includes both external threats, such as microbes or viruses, and internal threats which includes damage to organs, such as cholesterol deposits in the arteries, damage in the kidneys or developing tumors.
One major commonality with many of these conditions is the presence of an immune response, such as the presence of inflammatory cells flocking to the site of a myocardial infarction, an inflammatory response in damaged kidneys or immune cells attacking developing malignancies. “You have this inflammatory component that is initially trying to help, and then is damaging,” Merad said. “The immune system can sometimes help, if you reactivate it, or it can damage, in which case you have to modulate it.”
Immunotherapy for cancer
The discovery of the checkpoint inhibitors that act as a brake for T cells, which help defend against microbes, viruses and cancer cells, and an antibody that blocks its “braking” action, led to the first immunotherapy for cancer.
The scientists who made this discovery, Jim Alison and Tasuku Honjo, were awarded the 2018 Nobel Prize in Physiology and Medicine for their work. As a result of these new therapies, the prognosis of certain types of cancers, such as a subset of patients with metastatic melanoma or lung cancer, has been transformed. “We have doubled their life expectancy,” Merad said.
Merad believes the various molecules found in the immune system represent opportunities to develop therapies against a number of conditions. “The checkpoint is targeting only two molecules of the immune system, but we know that there are 100s, if not 1000s of molecules that are regulating the immune system,” all of which can be potential therapeutic targets.
Aging and inflammation
Aging has also emerged as an inflammatory condition, with inflammation now considered a hallmark of aging. This phenomenon may result from the immune system’s response to the accumulated damage that is found in organs as time progresses, Merad said. “Because your organs are aging, there is more damage,” Merad added. “The immune system is constantly realizing it has to eliminate all these things,” which leads to higher levels of inflammation as time progresses.
Rachel Fairbank is an independent journalist based in Houston, Texas. She has written for outlets such as National Geographic, Nature, Texas Monthly, the Houston Chronicle, the Washington Post and the New York Times.
