This study, executed by the group of Marcus Thelen and published in PLOS Biology, generated a comprehensive map of three atypical chemokine receptors in different organs. It provides a solid steppingstone for future functional explorations of ACKRs based on their anatomical localization.
Cells in our body are able to move around, and their local journeys are directed by following concentration gradients of molecules known as chemokines. The formation of these sharp gradients is generated with the help atypical chemokine receptors (ACKRs), which scavenge and remove chemokines from the extracellular environment. However, the precise anatomical location of ACKRs in various organs had never been mapped. In this study, we used genetically engineered mice expressing fluorescent proteins in place of ACKR3, ACKR4 and a novel ACKR, GPR182 (ACKR5), and fluorescently-labelled chimeric chemokines, to reveal their expression by fluorescence microscopy. We revealed unique and shared distribution patterns, predominantly in lymph and blood vessels, which we think allows them to direct the traffic of cells present in these "highways" of the body. By using this knowledge, researchers will now be able to study their function and collaboration in different organs.
One of the images was selected as Biomedical Picture of the Day by the Medical Research Council (UK).
The image depicts a 3D reconstruction using fluorescent microscopy of a kidney glomerulus which shows the chimeric chemokine CXCL11_20 in red and ACKR3 in green. Blood vessels (CD31) are in grey and podocytes (PDPN) are in blue.