Raising the Rae-1 flag

Raising a flag is a good way to send a message. In fact, that’s all it takes for a stressed-out, potentially cancerous cell to get the attention of the ever-watchful immune system. Until now, models of immune surveillance have assumed that only foreign danger signals or well-established inflammation could trigger a protective response.

But a new Yale study published in the February issue of Nature Immunology reports that cell-surface expression of Rae-1, a protein associated with milder forms of cell dysregulation, is enough to kick the immune system into action.

When the Rae-1 flag was raised in the skin cells of transgenic mice, local T cells and Langerhans cells became activated, changed their shape, communicated and moved out of the area to launch an immune response. It may be the earliest identified immune response to a potentially cancerous cell, says Michael Girardi, M.D., associate professor of dermatology, whose team worked with researchers from King’s College London School of Medicine and the University of Minnesota.

“Now that we have a starting point for the immune surveillance of cancer,” says Girardi, “we can begin to look at how it all unfolds.”