title: The Ixodes scapularis salivary protein, salp15, prevents the association of HIV-1 gp120 and CD4.
abstract: Ixodes scapularis salivary protein, Salp15, inhibits CD4(+) T cell activation by binding to the most-extracellular domains of the CD4 molecule, potentially overlapping with the gp120-binding region. We now show that Salp15 inhibits the interaction of gp120 and CD4. Furthermore, Salp15 prevents syncytia formation between HL2/3 (a stable HeLa cell line expressing the envelope protein) and CD4-expressing cells. Salp15 prevented gp120-CD4 interaction at least partially through its direct interaction with the envelope glycoprotein. A phage display library screen provided the interacting residues in the C1 domain of gp120. These results provide a potential basis to define exposed gp120 epitopes for the generation of neutralizing vaccines.
authors.affiliation: Department of Veterinary and Animal Sciences, University of Massachusetts Amherst, 103 Paige Laboratory, 161 Holdsworth Way, Amherst, MA 01003, USA.
authors.forename: Ignacio J
authors.initials: IJ
authors.lastname: Juncadella
authors.forename: Renu
authors.initials: R
authors.lastname: Garg
authors.forename: Tonya C
authors.initials: TC
authors.lastname: Bates
authors.forename: Elias R
authors.initials: ER
authors.lastname: Olivera
authors.forename: Juan
authors.initials: J
authors.lastname: Anguita
mesh_terms: D000595:Amino Acid Sequence; D015704:CD4 Antigens / Q000276:immunology / Q000378:metabolism*; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D002460:Cell Line; D006678:HIV / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D015699:HIV Envelope Protein gp120 / Q000276:immunology / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D007166:Immunosuppressive Agents / Q000494:pharmacology*; D008969:Molecular Sequence Data; D019151:Peptide Library; D012471:Salivary Proteins and Peptides / Q000494:pharmacology*
chemical_list: D015704:CD4 Antigens; D015699:HIV Envelope Protein gp120; D007166:Immunosuppressive Agents; D019151:Peptide Library; D012471:Salivary Proteins and Peptides; C464566:Salp15 protein, Ixodes scapularis