ACKR2: An Atypical Chemokine Receptor Regulating Lymphatic Biology.

The lymphatic system plays an important role in the induction of the immune response by transporting antigens, inflammatory mediators, and leukocytes from peripheral tissues to draining lymph nodes (LNs). It is emerging that lymphatic endothelial cells (LECs) are playing an active role in this context via the expression of chemokines, inflammatory mediators promoting cell migration, and chemokine receptors. Particularly, LECs express atypical chemokine receptors (ACKRs), which are unable to promote conventional signaling and cell migration whilst they are involved in the regulation of chemokine availability. Here we provide a summary of the data on the role of ACKR2 expressed by lymphatics, indicating an essential role for this ACKRs in the regulation of the inflammation and the immune response in different pathological conditions, including infection, allergy, and cancer.