Journal article
Human recombinant CD4 and CD4-derived synthetic peptides agglutinate immunoglobulin-coated latex particles. Evidence that residues 25–28 and 35–38 of human CD4 form two separate immunoglobulin binding sites
Molecular immunology, Vol.32(17), pp.1399-1404
1995
DOI: 10.1016/0161-5890(95)00096-8
PMID: 8643109
Abstract
It has been shown previously that amino acid residues 21–49 of the first extracellular domain of human CD4 form the core of an immunoglobulin (Ig) binding site. Synthetic peptides of human CD4 that encompass this region also bind Ig and, with higher affinity, antigen/antibody complexes. Synthetic peptides also enhance binding of both monomeric and aggregated Ig to monocytic U937 cells and
Staphylococcus aureus Protein A.
To better characterize the nature of the Ig binding site on CD4, we tested the ability of human recombinant CD4 (rCD4) to agglutinate polystyrene particles coated with Ig. Evidence is presented that soluble rCD4 and CD4 peptide (p)21–49 were capable of specific agglutination of polystyrene particles coated with polyclonal Ig of either human or sheep origin. Agglutination could be blocked by soluble human polyclonal IgG or F(ab′)
2 fragments. Both heparin and sulfated dextrans also inhibit agglutination, suggesting that charged residues on rCD4 played an important role in agglutination mediated by rCD4 or CD4 peptide. Similarly, aurintricarboxylic acid (ATA) also blocked agglutination of Ig-coated particles by rCD4. Agglutination mapping studies performed using truncated peptides revealed the existence of two discrete, closely related Ig binding sites (residues 25–28 and 35–38).
Details
- Title: Subtitle
- Human recombinant CD4 and CD4-derived synthetic peptides agglutinate immunoglobulin-coated latex particles. Evidence that residues 25–28 and 35–38 of human CD4 form two separate immunoglobulin binding sites
- Creators
- Petar Lenert - Research Center, Notre-Dame Hospital, University of Montréal, Montréal, Québec, Canada H2L 4M1Gordana Lenert - Research Center, Notre-Dame Hospital, University of Montréal, Montréal, Québec, Canada H2L 4M1Maurizio Zanetti - Department of Medicine and Cancer Center, 9500 Gilman Drive, University of California, San Diego, CA 92093-0063, U.S.A
- Resource Type
- Journal article
- Publication Details
- Molecular immunology, Vol.32(17), pp.1399-1404
- Publisher
- Elsevier Ltd
- DOI
- 10.1016/0161-5890(95)00096-8
- PMID
- 8643109
- ISSN
- 0161-5890
- eISSN
- 1872-9142
- Language
- English
- Date published
- 1995
- Academic Unit
- Immunology; Internal Medicine
- Record Identifier
- 9984094640602771
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