As part of their protective role in the immune system, T cells bind to foreign molecules in the body, known as antigens – a process now harnessed in immunotherapies to treat diseases like cancers. Exploring how receptors on the surface of T cells connect with antigens, researchers recently demonstrated that this process is highly sensitive to the spacing of antigens, and their closeness to the T cell. They designed an array of antigens (pictured, in red), whose positions could be manipulated with nanoscale precision; in this image, a T cell has contacted several antigens, generating a reaction shown in green. Antigens that were tightly packed and in closer contact with the T cell were more effective in triggering a response, as these arrangements force the protein CD45, which otherwise hinders binding, away from the receptors. Providing exceptionally-detailed insights into molecular mechanisms, these results have important implications for designing effective T-cell-based immunotherapies.
Written by Emmanuelle Briolat
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