Abstract
Infection of mononuclear cells by human immunodeficiency virus (HIV) begins with binding of the viral envelope glycoprotein, gp120, to its receptor, CD4. CD4 contains four extracellular immunoglobulin-like domains, the first of which (V1) is sufficient for HIV binding. V1 contains three sequences homologous to the antigen-complementarity-determining regions (CDR1 to -3) of immunoglobulin variable domains. While all three immunoglobulin CDRs are involved in antigen binding, only amino acids within and flanking the CDR2-like region of CD4 have been shown previously to be involved in gp120 binding. To investigate whether other regions in V1 take part in gp120 binding, we substituted alanine for each of 64 amino acids, including all of the hydrophilic residues in this domain. Mutations at four locations outside the CDR2-like sequence (amino acids 29, 59-64, 77-81, and 85) markedly affected gp120 binding, but not the overall structure of V1 as probed with eight conformationally sensitive monoclonal antibodies. Thus, the gp120-binding site of CD4 is not limited to the CDR2-like sequence and consists of several discontinuous segments. Several amino acids were identified that are critical for the conformation of V1; the importance of these residues suggests some differences in the folding of this domain compared to immunoglobulin variable domains. Three amino acid substitutions were found that increase the affinity for gp120 significantly (1.7- to 2-fold individually and 4.2-fold when combined), suggesting that it may be possible to improve the HIV-blocking ability of CD4-based molecules by increasing their gp120 binding affinity.
Full text
PDFImages in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Arthos J., Deen K. C., Chaikin M. A., Fornwald J. A., Sathe G., Sattentau Q. J., Clapham P. R., Weiss R. A., McDougal J. S., Pietropaolo C. Identification of the residues in human CD4 critical for the binding of HIV. Cell. 1989 May 5;57(3):469–481. doi: 10.1016/0092-8674(89)90922-7. [DOI] [PubMed] [Google Scholar]
- Bates P. A., McGregor M. J., Islam S. A., Sattentau Q. J., Sternberg M. J. A predicted three-dimensional structure for the human immunodeficiency virus binding domains of CD4 antigen. Protein Eng. 1989 Oct;3(1):13–21. doi: 10.1093/protein/3.1.13. [DOI] [PubMed] [Google Scholar]
- Bernstein F. C., Koetzle T. F., Williams G. J., Meyer E. F., Jr, Brice M. D., Rodgers J. R., Kennard O., Shimanouchi T., Tasumi M. The Protein Data Bank: a computer-based archival file for macromolecular structures. J Mol Biol. 1977 May 25;112(3):535–542. doi: 10.1016/s0022-2836(77)80200-3. [DOI] [PubMed] [Google Scholar]
- Brodsky M. H., Warton M., Myers R. M., Littman D. R. Analysis of the site in CD4 that binds to the HIV envelope glycoprotein. J Immunol. 1990 Apr 15;144(8):3078–3086. [PubMed] [Google Scholar]
- Byrn R. A., Mordenti J., Lucas C., Smith D., Marsters S. A., Johnson J. S., Cossum P., Chamow S. M., Wurm F. M., Gregory T. Biological properties of a CD4 immunoadhesin. Nature. 1990 Apr 12;344(6267):667–670. doi: 10.1038/344667a0. [DOI] [PubMed] [Google Scholar]
- Capon D. J., Chamow S. M., Mordenti J., Marsters S. A., Gregory T., Mitsuya H., Byrn R. A., Lucas C., Wurm F. M., Groopman J. E. Designing CD4 immunoadhesins for AIDS therapy. Nature. 1989 Feb 9;337(6207):525–531. doi: 10.1038/337525a0. [DOI] [PubMed] [Google Scholar]
- Chao B. H., Costopoulos D. S., Curiel T., Bertonis J. M., Chisholm P., Williams C., Schooley R. T., Rosa J. J., Fisher R. A., Maraganore J. M. A 113-amino acid fragment of CD4 produced in Escherichia coli blocks human immunodeficiency virus-induced cell fusion. J Biol Chem. 1989 Apr 5;264(10):5812–5817. [PubMed] [Google Scholar]
- Chaudhary V. K., Mizukami T., Fuerst T. R., FitzGerald D. J., Moss B., Pastan I., Berger E. A. Selective killing of HIV-infected cells by recombinant human CD4-Pseudomonas exotoxin hybrid protein. Nature. 1988 Sep 22;335(6188):369–372. doi: 10.1038/335369a0. [DOI] [PubMed] [Google Scholar]
- Clayton L. K., Hussey R. E., Steinbrich R., Ramachandran H., Husain Y., Reinherz E. L. Substitution of murine for human CD4 residues identifies amino acids critical for HIV-gp120 binding. Nature. 1988 Sep 22;335(6188):363–366. doi: 10.1038/335363a0. [DOI] [PubMed] [Google Scholar]
- Cunningham B. C., Wells J. A. High-resolution epitope mapping of hGH-receptor interactions by alanine-scanning mutagenesis. Science. 1989 Jun 2;244(4908):1081–1085. doi: 10.1126/science.2471267. [DOI] [PubMed] [Google Scholar]
- Deen K. C., McDougal J. S., Inacker R., Folena-Wasserman G., Arthos J., Rosenberg J., Maddon P. J., Axel R., Sweet R. W. A soluble form of CD4 (T4) protein inhibits AIDS virus infection. Nature. 1988 Jan 7;331(6151):82–84. doi: 10.1038/331082a0. [DOI] [PubMed] [Google Scholar]
- Epp O., Lattman E. E., Schiffer M., Huber R., Palm W. The molecular structure of a dimer composed of the variable portions of the Bence-Jones protein REI refined at 2.0-A resolution. Biochemistry. 1975 Nov 4;14(22):4943–4952. doi: 10.1021/bi00693a025. [DOI] [PubMed] [Google Scholar]
- Fisher R. A., Bertonis J. M., Meier W., Johnson V. A., Costopoulos D. S., Liu T., Tizard R., Walker B. D., Hirsch M. S., Schooley R. T. HIV infection is blocked in vitro by recombinant soluble CD4. Nature. 1988 Jan 7;331(6151):76–78. doi: 10.1038/331076a0. [DOI] [PubMed] [Google Scholar]
- Furey W., Jr, Wang B. C., Yoo C. S., Sax M. Structure of a novel Bence-Jones protein (Rhe) fragment at 1.6 A resolution. J Mol Biol. 1983 Jul 5;167(3):661–692. doi: 10.1016/s0022-2836(83)80104-1. [DOI] [PubMed] [Google Scholar]
- Hussey R. E., Richardson N. E., Kowalski M., Brown N. R., Chang H. C., Siliciano R. F., Dorfman T., Walker B., Sodroski J., Reinherz E. L. A soluble CD4 protein selectively inhibits HIV replication and syncytium formation. Nature. 1988 Jan 7;331(6151):78–81. doi: 10.1038/331078a0. [DOI] [PubMed] [Google Scholar]
- Lamarre D., Ashkenazi A., Fleury S., Smith D. H., Sekaly R. P., Capon D. J. The MHC-binding and gp120-binding functions of CD4 are separable. Science. 1989 Aug 18;245(4919):743–746. doi: 10.1126/science.2549633. [DOI] [PubMed] [Google Scholar]
- Landau N. R., Warton M., Littman D. R. The envelope glycoprotein of the human immunodeficiency virus binds to the immunoglobulin-like domain of CD4. Nature. 1988 Jul 14;334(6178):159–162. doi: 10.1038/334159a0. [DOI] [PubMed] [Google Scholar]
- Lasky L. A., Nakamura G., Smith D. H., Fennie C., Shimasaki C., Patzer E., Berman P., Gregory T., Capon D. J. Delineation of a region of the human immunodeficiency virus type 1 gp120 glycoprotein critical for interaction with the CD4 receptor. Cell. 1987 Sep 11;50(6):975–985. doi: 10.1016/0092-8674(87)90524-1. [DOI] [PubMed] [Google Scholar]
- Maddon P. J., Littman D. R., Godfrey M., Maddon D. E., Chess L., Axel R. The isolation and nucleotide sequence of a cDNA encoding the T cell surface protein T4: a new member of the immunoglobulin gene family. Cell. 1985 Aug;42(1):93–104. doi: 10.1016/s0092-8674(85)80105-7. [DOI] [PubMed] [Google Scholar]
- Maddon P. J., Molineaux S. M., Maddon D. E., Zimmerman K. A., Godfrey M., Alt F. W., Chess L., Axel R. Structure and expression of the human and mouse T4 genes. Proc Natl Acad Sci U S A. 1987 Dec;84(24):9155–9159. doi: 10.1073/pnas.84.24.9155. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Marquart M., Deisenhofer J., Huber R., Palm W. Crystallographic refinement and atomic models of the intact immunoglobulin molecule Kol and its antigen-binding fragment at 3.0 A and 1.0 A resolution. J Mol Biol. 1980 Aug 25;141(4):369–391. doi: 10.1016/0022-2836(80)90252-1. [DOI] [PubMed] [Google Scholar]
- Mizukami T., Fuerst T. R., Berger E. A., Moss B. Binding region for human immunodeficiency virus (HIV) and epitopes for HIV-blocking monoclonal antibodies of the CD4 molecule defined by site-directed mutagenesis. Proc Natl Acad Sci U S A. 1988 Dec;85(23):9273–9277. doi: 10.1073/pnas.85.23.9273. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nara P. L., Hwang K. M., Rausch D. M., Lifson J. D., Eiden L. E. CD4 antigen-based antireceptor peptides inhibit infectivity of human immunodeficiency virus in vitro at multiple stages of the viral life cycle. Proc Natl Acad Sci U S A. 1989 Sep;86(18):7139–7143. doi: 10.1073/pnas.86.18.7139. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Peterson A., Seed B. Genetic analysis of monoclonal antibody and HIV binding sites on the human lymphocyte antigen CD4. Cell. 1988 Jul 1;54(1):65–72. doi: 10.1016/0092-8674(88)90180-8. [DOI] [PubMed] [Google Scholar]
- Ponder J. W., Richards F. M. Tertiary templates for proteins. Use of packing criteria in the enumeration of allowed sequences for different structural classes. J Mol Biol. 1987 Feb 20;193(4):775–791. doi: 10.1016/0022-2836(87)90358-5. [DOI] [PubMed] [Google Scholar]
- Robey E., Axel R. CD4: collaborator in immune recognition and HIV infection. Cell. 1990 Mar 9;60(5):697–700. doi: 10.1016/0092-8674(90)90082-p. [DOI] [PubMed] [Google Scholar]
- Sattentau Q. J., Arthos J., Deen K., Hanna N., Healey D., Beverley P. C., Sweet R., Truneh A. Structural analysis of the human immunodeficiency virus-binding domain of CD4. Epitope mapping with site-directed mutants and anti-idiotypes. J Exp Med. 1989 Oct 1;170(4):1319–1334. doi: 10.1084/jem.170.4.1319. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sattentau Q. J., Weiss R. A. The CD4 antigen: physiological ligand and HIV receptor. Cell. 1988 Mar 11;52(5):631–633. doi: 10.1016/0092-8674(88)90397-2. [DOI] [PubMed] [Google Scholar]
- Saul F. A., Amzel L. M., Poljak R. J. Preliminary refinement and structural analysis of the Fab fragment from human immunoglobulin new at 2.0 A resolution. J Biol Chem. 1978 Jan 25;253(2):585–597. [PubMed] [Google Scholar]
- Segal D. M., Padlan E. A., Cohen G. H., Rudikoff S., Potter M., Davies D. R. The three-dimensional structure of a phosphorylcholine-binding mouse immunoglobulin Fab and the nature of the antigen binding site. Proc Natl Acad Sci U S A. 1974 Nov;71(11):4298–4302. doi: 10.1073/pnas.71.11.4298. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sheriff S., Silverton E. W., Padlan E. A., Cohen G. H., Smith-Gill S. J., Finzel B. C., Davies D. R. Three-dimensional structure of an antibody-antigen complex. Proc Natl Acad Sci U S A. 1987 Nov;84(22):8075–8079. doi: 10.1073/pnas.84.22.8075. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Smith D. H., Byrn R. A., Marsters S. A., Gregory T., Groopman J. E., Capon D. J. Blocking of HIV-1 infectivity by a soluble, secreted form of the CD4 antigen. Science. 1987 Dec 18;238(4834):1704–1707. doi: 10.1126/science.3500514. [DOI] [PubMed] [Google Scholar]
- Suh S. W., Bhat T. N., Navia M. A., Cohen G. H., Rao D. N., Rudikoff S., Davies D. R. The galactan-binding immunoglobulin Fab J539: an X-ray diffraction study at 2.6-A resolution. Proteins. 1986 Sep;1(1):74–80. doi: 10.1002/prot.340010112. [DOI] [PubMed] [Google Scholar]
- Till M. A., Ghetie V., Gregory T., Patzer E. J., Porter J. P., Uhr J. W., Capon D. J., Vitetta E. S. HIV-infected cells are killed by rCD4-ricin A chain. Science. 1988 Nov 25;242(4882):1166–1168. doi: 10.1126/science.2847316. [DOI] [PubMed] [Google Scholar]
- Traunecker A., Lüke W., Karjalainen K. Soluble CD4 molecules neutralize human immunodeficiency virus type 1. Nature. 1988 Jan 7;331(6151):84–86. doi: 10.1038/331084a0. [DOI] [PubMed] [Google Scholar]
- Traunecker A., Schneider J., Kiefer H., Karjalainen K. Highly efficient neutralization of HIV with recombinant CD4-immunoglobulin molecules. Nature. 1989 May 4;339(6219):68–70. doi: 10.1038/339068a0. [DOI] [PubMed] [Google Scholar]
- Williams A. F., Barclay A. N. The immunoglobulin superfamily--domains for cell surface recognition. Annu Rev Immunol. 1988;6:381–405. doi: 10.1146/annurev.iy.06.040188.002121. [DOI] [PubMed] [Google Scholar]