CCR5 deficiency/CCR5Δ32: resistant to HIV infection at the cost of curtailed CD4 T cell memory responses.

Orchestrated trafficking and activation by pathogen-derived peptides define the ability of CD4 T helper cells to contribute to an effective adaptive immunity. In this issue of The EMBO Journal, Martín-Leal et al show that the inflammatory chemokine receptor CCR5, well known for its role in cell migration and HIV infection, regulates ceramide synthesis and TCR nanoclustering to promote memory CD4 T cell activation.