When Michelle Krogsgaard's lab engineered T cells to recognize a single chemical tag on cancer cells, something remarkable happened: in mice with leukemia, the immune cells hunted down and eliminated the disease entirely. That 2023 breakthrough, published in Nature Communications, represented far more than a laboratory curiosity—it signaled a fundamental shift in how scientists might craft tomorrow's cancer treatments, moving away from one-size-fits-all approaches toward therapies tailored to each patient's unique tumor.
For decades, metastatic cancer meant chemotherapy, a blunt instrument that destroyed healthy cells along with malignant ones. Immunotherapy changed that calculus by enlisting the body's own T cells—the immune system's frontline defenders—to recognize and kill tumors. Yet the strategy harbors a deep vulnerability. Tumors are master deceivers. They mutate or hide the telltale protein flags, called antigens, that T cells use to identify cancer. Like burglars disabling an alarm system, cancer cells cloak themselves from immune recognition, rendering even powerful treatments helpless. "Immunotherapy has had a huge impact in fighting metastatic cancers and leukemias when no other treatments have worked," says Dr. Krogsgaard, an immunologist at NYU Langone Health's Perlmutter Cancer Center. "But we need to understand exactly how and why."
Her lab has spent recent years peering into that molecular darkness. In their 2023 study, Dr. Krogsgaard's team identified an unusual cancer marker: a fragment of protein bearing a phosphate—a tiny chemical tag that appears only on tumor versions, making it invisible to the immune system in healthy cells. When researchers engineered T cells specifically trained to recognize that tagged protein, the results in leukemia-bearing mice spoke for themselves: complete tumor elimination.
The discoveries have only accelerated. A 2024 Nature Communications paper unveiled another breakthrough: a cancer antigen created by genetic mutation that alters the protein's shape in ways that actually enhance T-cell recognition, supercharging the immune response. Concurrent research from Dr. Krogsgaard's lab employed biophysical imaging to reveal an elegant mechanism at work—mechanical forces and the natural movement of proteins within the cell membrane affect how T-cell receptors grip and flex, activating immune cells without altering what they recognize.
Yet understanding the mechanism is only half the battle. Tumors also deploy partner proteins to escape detection. Dr. Krogsgaard recently demonstrated that a protein called FGL-1 works alongside LAG-3, a well-known immune evasion factor, to help cancer cells dodge T-cell attacks. When clinicians combined three checkpoint inhibitors targeting these escape routes, patients responded better and experienced fewer side effects. But as Dr. Krogsgaard notes, nobody quite understood why. Deciphering these partnerships opens new therapeutic possibilities—identifying targets that hit multiple signaling pathways simultaneously, rather than blocking one protein at a time only to watch others step in, like a game of molecular Whac-A-Mole.
The implications ripple outward. "We can use this combined knowledge to design cancer cell antigens that are more recognizable and elicit efficient T-cell responses," Dr. Krogsgaard explains. "This approach could lead to safer therapies by boosting receptor interactions without manipulating them directly." Her vision points toward a future where immunotherapy becomes precision medicine: treatments engineered not against cancer in general, but against the specific antigenic signature of each patient's tumor. Recently, the Pew Charitable Trusts recognized the potential, awarding Dr. Krogsgaard and collaborator Richard L. Possemato a prestigious Innovation Fund grant to explore how nutrient scarcity in tumors weakens T cells. With each discovery, the path toward personalized cancer fighting grows clearer.