How chemokine signalling and antigen recognition are integrated by T cells. (360G-Wellcome-107375_Z_15_Z)

Integration of diverse signals at the immunological synapse (IS) is fundamental to T-cell responses. Although its structure is well studied regarding the organisation of proteins directing cell-cell interactions, how signalling by G protein-coupled receptors (GPCRs) in general, and chemokine receptors in particular, is integrated at the IS is surprisingly poorly understood. This proposal aims to characterise spatiotemporal chemokine receptor organisation within the IS using confocal and single-m olecule microscopy of four receptors of particular interest. The mechanisms mediating receptor organisation will be elucidated by reconstructing the antigen-presenting cell surface with artificial bilayers, and using interaction-deficient receptor mutants. I will examine the IS-dependency of signal-integration by visualising signalling events therein in the presence and absence of chemokine gradients, and by perturbing normal IS organisation, complementing imaging with biochemical assays. I will also determine which of the 54 Rhodopsin-family GPCRs expressed natively by T cells participate in cellular activation through systematic knock-outs; comprising the first system-level analysis of T-cell GPCR function. This will provide new insights into the extent to which GPCR function is enhanced at IS-like structures and the importance of these structures for lymphocyte cell-cell communication generally. This research also has the potential to identify new immunologically and/or pharmacologi cally active receptors.