C-, Xenopus/Amphibian,-C chemokine receptor type 4 (C, Xenopus/Amphibian,CR-4, CD184) is a receptor for the C-, Xenopus/Amphibian,-C chemokine C, Xenopus/Amphibian,CL12 (SDF-1) that transduces a signal by increasing intracellular calcium ions levels and enhancing MAPK1/MAPK3 activation. CD184 also acts as a receptor for e, Xenopus/Amphibian,tracellular ubiquitin. CD184 is involved in haemostasis, in cardiac ventricular septum formation and acts as a coreceptor with CD4 for HIV-1 isolates. Defects in CD184 are a cause of WHIM syndrome (warts, hypogammaglobulinemia, infections and myelokathe, Xenopus/Amphibian,is).