Cellular Architecture Has Major Influence on Cell Fate Decisions

Researchers from the Institute of Molecular Systems Biology at ETH Zurich have uncovered the pivotal role played by the subcellular spatial organization, or cellular architecture, of cytotoxic T cells in determining their fate.

The team combined high-throughput fluorescence microscopy with deep learning–based single-cell image analysis to analyze images of thousands of T cells from healthy volunteers. Their findings revealed unexpected differences in the cellular architecture of these immune cells, which could be classified into three distinct groups.

One group, characterized by T cells with nuclear invaginations, exhibited a remarkable ability to rapidly activate and transform into powerful effector cells, capable of proliferating quickly and eliminating pathogens. In contrast, the round T cells without nuclear invaginations followed a more leisurely path, eventually differentiating into long-lived memory cells that provide future protection against the same pathogen.

Benjamin Hale, lead author of the study published in Science, emphasized the significance of their discovery: "We didn't expect the platform to split the round cells into two different groups." Further investigation unveiled that the differences in cellular architecture between these two classes of round cells also had functional implications.

The cells with nuclear invaginations are designed to activate rapidly: many of them convert into bottle-shaped effector cells within 24 hours. They also mount a stronger response when activated—and they proliferate much faster than cells without nuclear invaginations. The researchers identified the molecular mechanism behind this heightened activation, attributing it to the increased influx of calcium ions facilitated by the unique cellular architecture.

While many questions remain unanswered, the researchers are excited about the potential applications of their findings, particularly in the realm of cancer therapies. "Many novel therapies use T cells to kill cancer cells," senior author Berend Snijder noted. "If we can find a way to specifically select and deploy these cellular architectures, we may be able to improve the clinical efficacy of such therapies."