T cells of the immune system found to self-activate via interaction of two proteins – B7 and CD28 – displayed on their surface
Our cell membranes look “like a coastline with lots of coves and bays” says Enfu Hui, lead of a team of scientists who recently found a secret on the shores of this T cell (highlighted with fluorescent stains). A vital step in our immune response, T cells respond when presented with suspicious proteins called antigens found on the outside of pathogens like viruses, or cancers. A protein called B7 triggers another called CD28 on the T cells and they set off in pursuit of the pathogen. The team found that T cells can make their own supply of B7 and, using the folds and crevices on their membranes, bring it into contact with CD28. This 'self-activation' might help scientists design drugs to 'top up' T cells with B7 while on protective missions inside our bodies, or even intercept overzealous T cells, such as those found in auto-immune diseases.
Written by
BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences the website aims to engage everyone, young and old, in the wonders of biomedicine. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.
BPoD is also available in Catalan at www.bpod.cat with translations by the University of Valencia.