       Document 0523
 DOCN  M9620523
 TI    Mapping the Ig superantigen-binding site of HIV-1 gp120.
 DT    9602
 AU    Goodglick L; Zevit N; Neshat MS; Braun J; Department of Pathology and
       Laboratory Medicine, Jonsson; Comprehensive Cancer Center, UCLA School
       of Medicine 90095, USA.
 SO    J Immunol. 1995 Dec 1;155(11):5151-9. Unique Identifier : AIDSLINE
       MED/96072787
 AB    The envelope glycoprotein, gp120, of HIV-1 has recently been identified
       as a member of the new family of Ig superantigens (Ig-SAg). This
       classification is based on the selective binding of gp120 to an
       unusually high proportion of endogenous, nonimmune Ig, and the selective
       activation of nonimmune B cells by gp120 in vitro. Many, if not all of
       the nonimmune Ig that bind to gp120 are members of the VH3 Ig gene
       family. The aim of this study was to determine the epitope on gp120 that
       was responsible for its Ig-SAg binding activity. To do this, we utilized
       a panel of 30 peptides derived from gp160 in a competition-binding
       assay. For five Igs that were tested, as well as for polyclonal serum
       IgM, two overlapping peptides (each 20 amino acids in length) were
       identified that were potent inhibitors of gp120 binding. Similarly, the
       10 amino acid overlap region of these two peptides had inhibitory
       activity. Thus, this decamer sequence represented the optimal Ig-SAg
       epitope or mimotope. The amino acid residue at position 1 of the
       decamer, and to a lesser extent at position 10, was critical for peptide
       binding. In addition to this decamer peptide, other peptides that shared
       modest sequence homology were also selectively inhibitory for specific
       Ig samples. These findings provide the first definition of an Ig-SAg
       ligand at the peptide level and will facilitate further structural and
       biologic characterization of this new class of pathogenic Ags.
 DE    Amino Acid Sequence  Antibodies, Monoclonal/IMMUNOLOGY  *Epitope Mapping
       Human  HIV Envelope Protein gp120/*METABOLISM  HIV-1/*IMMUNOLOGY
       IgM/IMMUNOLOGY/METABOLISM  Molecular Sequence Data  Peptides/IMMUNOLOGY
       Superantigens/*METABOLISM  Support, Non-U.S. Gov't  Support, U.S. Gov't,
       P.H.S.  JOURNAL ARTICLE

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).

