title: Mapping of the extracellular binding regions of the human interleukin-8 type B receptor.
abstract: This study was undertaken to define the regions of the human interleukin-8 type B receptor (IL8RB) which are critical for binding the ligands interleukin-8, NAP-2 and GRO alpha. Peptides corresponding to the N-terminus region and the first extracellular loop of the receptor demonstrated statistically significant (p = 0.001) inhibition of IL-8 control binding levels (inhibition levels of 73.0 +/- 5.1% and 89.9 +/- 2.2% respectively). In contrast, NAP-2 binding was inhibited only by the peptide representing the first extracellular loop (63.2 +/- 2.3%), while GRO alpha binding was inhibited by portions of the N-terminus (49.7 +/- 14.9% and 41.8 +/- 14.9%), but not the first extracellular loop. We suggest that: a) the chemokine receptor IL8RB, known to bind three related ligands with high affinity, seems to do so via distinct contact points and b.) the first extracellular loop is significant in the binding event.
authors.affiliation: Department of Oral Biology, State University of New York at Buffalo 14214-3092, USA.
authors.forename: J A
authors.initials: JA
authors.lastname: Katancik
authors.forename: A
authors.initials: A
authors.lastname: Sharma
authors.forename: S J
authors.initials: SJ
authors.lastname: Radel
authors.forename: E
authors.initials: E
authors.lastname: De Nardin
mesh_terms: D000595:Amino Acid Sequence; D015703:Antigens, CD / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D001665:Binding Sites / Q000235:genetics; D002460:Cell Line; D054360:Chemokine CXCL1; D019743:Chemokines, CXC; D002630:Chemotactic Factors / Q000378:metabolism; D002874:Chromosome Mapping; D005110:Extracellular Space / Q000378:metabolism; D006133:Growth Substances / Q000378:metabolism; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins; D016209:Interleukin-8 / Q000378:metabolism; D008024:Ligands; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000235:genetics / Q000378:metabolism; D010455:Peptides / Q000378:metabolism; D011485:Protein Binding; D018123:Receptors, Interleukin / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D023062:Receptors, Interleukin-8A; D014162:Transfection; D001620:beta-Thromboglobulin
chemical_list: D015703:Antigens, CD; C475829:CXCL1 protein, human; D054360:Chemokine CXCL1; D019743:Chemokines, CXC; D002630:Chemotactic Factors; D006133:Growth Substances; D036341:Intercellular Signaling Peptides and Proteins; D016209:Interleukin-8; D008024:Ligands; C061615:PPBP protein, human; D010446:Peptide Fragments; D010455:Peptides; D018123:Receptors, Interleukin; D023062:Receptors, Interleukin-8A; D001620:beta-Thromboglobulin; C009862:connective tissue-activating peptide