Chemokine DARC binding

Fig. 1 Model of erythrocyte DARC function in the prostate cancer microenvironment. Expression of erythrocyte DARC binds and clears angiogenic ELR+CXC chemokines from the tumor. However, lack of the erythrocyte DARC results in a higher than normal intratumor concentration of angiogenic chemokines...

Choe, H., Moore, M. J., Owens, C. M., Wright, P. L., Vasilieva, N., Li, W., Singh, A. P., Shakri, R., Chitnis, C. E., and Farzan, M. (2005). Sulphated tyrosines mediate association of chemokines and Plasmodium vivax Duffy binding protein with the Duffy antigen/ receptor for chemokines (DARC). Mol. Microbiol. 55,1413-1422. 

There are two major classes of chemokine receptors. The CC receptors bind to the CC chemokines and are named CCRl to 9 the CXC chemokines selectively bind to the CXC receptors, termed CXCRl to CXCR5. This group also comprises receptors for fractalkine (CX3CRI) and lymphotactin (XCRl), as well as the Duffy antigen receptor for chemokines (DARC), which has been shown to bind promiscuously to both CXC and CC chemokines. Finally, there is a receptor termed D6, which has been renamed CCRIO by some investigators. 

In patients not expressing the DARC on erythrocytes, there is no binding of ELR+ chemokines end the intradumor concentration of these angiogenic mediators remains high... 

Walton, R.T. and Rowland-Jones, S.L. (2008) HIV and chemokine binding to red blood cells-DARC matters. Cell Host Microbe, 4, 3—5. 

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