Transmembrane domains and the regulation of trogocytosis in T cells

Interviewer: We're joined today by Dr. Stefano Barbera from Uppsala University who recently published a paper in Science Immunology, revealing how T cells can pass on chimeric antigen receptors to other T cells effectively equipping them with anti-tumor capabilities. Stefano, thank you very much for joining us today. Dr. Barbera: Thank you for having me. Interviewer: So to start, can you describe your key findings regarding the transfer of functional chimeric antigen receptors between T cells. Dr. Barbera: We have described in our recent publication that T cells can acquire chimeric antigen receptors from engineered CAR-T cells. This, in a nutshell, is what we have described. We've also shown that the chimeric antigen receptors remain functional on the recipient T cells, and we have seen that once the receiving T cells are equipped with the chimeric antigen receptors, they can target tumor antigens for which the CAR is specific to. In this way, they can trigger signaling pathways to activate themselves. This process was known that T cells could exchange molecules and antigen receptors, such as T cell receptors. This has also been shown for B cells. They can exchange B-cell receptors, and this phenomenon of molecules exchanged between immune cells is known as trogocytosis. Interviewer: Can you talk a little bit more about what you and your colleagues were able to show in this publication regarding the mechanisms underlying this transfer? Dr. Barbera: We have demonstrated mainly two key things. There are different hypotheses on how trogocytosis takes place.