Its name is derived from the Greek words for “big” and “eater”, and, as its name suggests, this type of cell has a fierce appetite<\/a> for cancer<\/a>.<\/p>\n Macrophages can even sound an “eat me” alarm<\/a> from within tumors, kicking other immune players like T Cells into action.<\/p>\n YouTube Thumbnail<\/p>\n They are a wonderful target for cancer research, but so far, next-generation therapies have largely failed to unlock their true potential.<\/p>\n A team led by scientists at the University of Southern California (USC) may have at last found the key.<\/p>\n They can now genetically engineer the cells that ultimately give rise to macrophages in the lab, or macrophage progenitor cells.<\/p>\n These are not stem cells<\/a>, but the cells that go on to form stem cells, and they seem to have a superpower up their sleeves:<\/p>\n They can make copies of themselves over and over.<\/p>\n “The prevailing view has been that long-term self-renewal in the blood system is primarily a property of the \u2026 stem cells that can generate any type of blood or immune cell,” explains<\/a> biologist Qi-Long Ying at USC.<\/p>\n “We found that, under the right conditions, [progenitors] can also self-renew, dividing extensively while keeping their identity and ability to produce functional immune cells.”<\/p>\n “That gives us a scalable starting point for engineering cell therapies for cancer, infectious disease, and potentially many other conditions.”<\/p>\n CAR-T is a famous and groundbreaking cancer therapy<\/a> that requires taking a patient’s T cells<\/a>, genetically engineering them to better fight cancer, and then infusing them back into the body’s circulation.<\/p>\n So far, versions of CAR-T have shown remarkable success, significantly extending the lives of patients in clinical trials<\/a>.<\/p>\n But while they work best for cancer in the blood<\/a>, they don’t work as well against solid tumors.<\/p>\n Typically, macrophages are the most abundant immune cells within a cancerous mass, but they are more challenging to engineer in the lab.<\/p>\n These white blood cells have also proven difficult to grow outside the human body, often failing to proliferate to necessary levels.<\/p>\n What’s more, they are tricky to freeze and store long-term.<\/p>\n But all hope is not lost for a therapy like CAR-M, which is similar to CAR-T<\/a>, but with macrophages instead of T-cells.<\/p>\n Subscribe to ScienceAlert’s free fact-checked newsletter<\/p>\n The progenitor cells of macrophages, called granulocyte-monocyte progenitors (GMPs), could be the ticket.<\/p>\n Using mouse and human GMPs, Ying and colleagues have figured out exactly what these cells need to eat to grow, feeding them a complex mix of chemicals at very specific stages.<\/p>\n The hope is that this endless supply of GMPs can now be used for future cancer immunotherapies.<\/p>\n In the lab, engineered GMPs generated potent CAR-Ms.<\/p>\n When these lab-grown GMPs were injected into mice with blood cancer and solid tumors, researchers found that the progenitor cells generated a steady supply of macrophages and other immune players.<\/p>\n Unlike injected macrophages, these GMPs spread throughout the rodent body and stalled the cancer’s progression in blood and in solid tumors.<\/p>\n “This method for the expansion and engineering of GMPs opens the door to numerous translational applications, much like T cell expansion and engineering,” says<\/a> biologist and collaborator Ravi Majeti from Stanford University.<\/p>\n “We have already demonstrated engineering of these cells to drive multiple potent functions, and there is a lot more to be explored.”<\/p>\n Related: New Immune System Discovery Could Help Beat a Sneaky Cancer Cell Trick<\/a><\/p>\n For many years, scientists have tried to determine which T cells are best to re-engineer for CAR-T therapies. This new research, however, suggests that targeting the progenitors of immune cells is a potentially better route to success, covering more bases all at once.<\/p>\n “Our study suggests that the future of immunotherapy may depend not only on designing better CAR receptors<\/a>, but also on choosing the right developmental stage of the cell,” concludes<\/a> Ying.<\/p>\n The study is published in Cell<\/a>.<\/p>\n This article was fact-checked by Jess Cockerill<\/a> and edited by Michelle Starr<\/a>. While we pride ourselves on our process, we are only human. If you spot a mistake, please let us know<\/a>.<\/p>\n![\"YouTube](\"https:\/\/www.newsbeep.com\/ie\/wp-content\/uploads\/2026\/07\/18d6d2549d427a118c33af4ba6bb4c5e.jpeg\"\/)
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Macrophages injected into mice did not proliferate around the body as GMPs did. (Yue et al., Cell<\/a>, 2026)<\/p>\n