S1PR5 and infection: S1PR4, expressed on leukocytes, NK cells and airway SMC [168], and S1PR5 expressed on NK cells and oligodendrocytes [169] have not been associated with atheroprogression to date, even though S1PR4 stimulates IL-10 secretion from T-cells and simultaneously inhibits interleukin 4 and interferon-γ production [170], while S1PR5 mobilizes NK cells during infections.