| First Author | Liu Y | Year | 1999 |
| Journal | J Biol Chem | Volume | 274 |
| Issue | 33 | Pages | 23387-95 |
| PubMed ID | 10438516 | Mgi Jnum | J:56899 |
| Mgi Id | MGI:1342876 | Doi | 10.1074/jbc.274.33.23387 |
| Citation | Liu Y, et al. (1999) Identification of a CD4 domain required for interleukin-16 binding and lymphocyte activation. J Biol Chem 274(33):23387-95 |
| abstractText | Interleukin-16 (IL-16) activates CD4(+) cells, possibly by direct interaction with CD4. IL-16 structure and function are highly conserved across species, suggesting similar conservation of a putative IL-16 binding site on CD4. Comparison of the human CD4 amino acid sequence with that of several different species revealed that immunoglobulin-like domain 4 is the most conserved extracellular region. Potential interaction of this domain with IL-16 was studied by testing murine D4 sequence-based oligopeptides for inhibition of IL-16 chemoattractant activity and inhibition of IL-16 binding to CD4 in vitro. Three contiguous 12-residue D4 region peptides (designated A, B, and C) blocked IL-16 chemoattractant activity, with peptide B the most potent. Peptides A and B were synergistic for inhibition, but peptide C was not. Peptides A and B also blocked IL-16 binding to CD4 in vitro, whereas peptide C did not. CD4, in addition to its known function as a receptor for major histocompatibility complex class II, contains a binding site for IL-16 in the D4 domain. The D4 residues required for IL-16 binding overlap those previously shown to participate in CD4-CD4 dimerization following class II major histocompatibility complex binding, providing a mechanistic explanation for the known function of IL-16 to inhibit the mixed lymphocyte reaction. |
