1
|
Ecker B, Vollenhofer S, Bares T, Schalkhammer T, Schinkinger M, Pittner F. Overexpression and purification of a recombinant chimeric HIV type 2/HIV type 1 envelope peptide and application in an accelerated immunobased HIV type 1/2 antibody detection system (AIBS): a new rapid serological screening assay. AIDS Res Hum Retroviruses 1996; 12:1081-91. [PMID: 8844013 DOI: 10.1089/aid.1996.12.1081] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
A chimeric HIV-2/HIV-1 envelope sequence containing an immunodominant region of HIV-2 gp36 and the corresponding region of HIV-1 gp41 was constructed and overexpressed in Escherichia coli. The recombinant product (rp21/18) was purified and applied in a novel antibody-screening assay. Characteristics in the design of this new principle are as follows: (1) the overall assay time is about 30 min; (2) the assay procedure includes three manipulation steps; and (3) the test shows a reliable performance with respect to sensitivity and specificity. The diluted serum sample and the protein G-horseradish peroxidase conjugate are added simultaneously into a coated (hybrid antigen HIV-1/2) and blocked microtiter plate well. The in-batch incubation of serum sample with protein G-horseradish peroxidase saves two manipulation steps that are normally necessary in the five-step procedure of a classical ELISA. AIBS was evaluated with commercially available seroconversion panels and with random negative serum samples from a blood bank. Seroconversion results demonstrated that AIBS has equivalent sensitivity to ELISAs and the third generation assays. The specificity was determined on a total blood donor population of 5012 (Red Cross Vienna, Austria). The repeat reactive rates for donor population were 0.02%. AIBS represents a general immunometric system (not only HIV antibodies). The entire assay procedure of AIBS evaluated for HIV-1/2 screening, including result reporting, can be performed automatically by several commercially available systems. Depending on these systems AIBS is potentially useful in laboratories or blood banks that have both high- and low-volume testing.
Collapse
Affiliation(s)
- B Ecker
- University of Vienna, Institute of Biochemistry and Molecular Cell Biology, Austria
| | | | | | | | | | | |
Collapse
|
2
|
Hodge DR, Chen YM, Samuel KP. Oligomerization of the HIV type 2 Nef protein: mutational analysis of the heptad leucine repeat motif and cysteine residues. AIDS Res Hum Retroviruses 1995; 11:65-79. [PMID: 7734198 DOI: 10.1089/aid.1995.11.65] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The human immunodeficiency virus type 2 (HIV-2) Nef protein expressed in Escherichia coli forms highly stable homooligomeric complexes in vitro. Similarly, the native protein synthesized in the persistently infected H9 T cell line also forms stable homooligomers in vivo. To determine whether homooligomer formation is mediated by the leucine zipper-type sequence located in the middle region of the protein, site-directed mutagenesis was used to introduce double and triple point mutations at heptad leucine positions L1, L2, and L4 within the HIV-2NIHZ Nef protein sequence. Here, we show that substitution of a serine residue for the L1 (residue 108) and L2 (residue 115) heptad leucines, and a glutamine residue for the L4 (residue 129) heptad leucine, did not prevent Nef homooligomer formation in vitro. However, a more drastic substitution of alpha-helix-breaking proline residue for the L2 and L4 heptad leucines significantly abrogated ability of the protein to form stable homooligomers. In addition, because significantly higher levels of the Nef oligomers were consistently observed under the nonreducing SDS-PAGE condition, site-specific mutagenesis was also used to examine the role of cysteine residues in generating disulfide-linked Nef dimers in vitro. Here, we also show that single cysteine-to-glycine substitutions at positions 28, 32, or 55 drastically reduced covalent Nef dimer formation and thermal stability of the Nef protein in vitro. Therefore, these results demonstrate that the leucine zipper-type motif in the HIV-2 Nef protein mediates stable homooligomer formation in vitro, and also establish a role for covalent disulfide bonds in the formation of linked Nef dimers and thermal stability of the monomer Nef in vitro.
Collapse
Affiliation(s)
- D R Hodge
- Laboratory of Molecular Oncology, National Cancer Institute, Frederick Research and Development Center, Maryland 21702, USA
| | | | | |
Collapse
|
3
|
Marlink R, Kanki P, Thior I, Travers K, Eisen G, Siby T, Traore I, Hsieh CC, Dia MC, Gueye EH. Reduced rate of disease development after HIV-2 infection as compared to HIV-1. Science 1994; 265:1587-90. [PMID: 7915856 DOI: 10.1126/science.7915856] [Citation(s) in RCA: 396] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Human immunodeficiency virus type-2 (HIV-2) is a close relative of the prototype acquired immunodeficiency syndrome (AIDS) virus, HIV-1. HIV-2 is biologically similar to HIV-1, but information is lacking concerning clinical outcomes of HIV-2-infected individuals. From 1985 to 1993, a prospective clinical study was conducted in women with HIV-2 and HIV-1 infection to determine and compare rates of disease development. HIV-1-infected women had a 67% probability of AIDS-free survival 5 years after seroconversion in contrast with 100% for HIV-2-infected women. In addition to having significantly less HIV-related disease outcome in HIV-2 enrollees compared to HIV-1 enrollees, the rate of developing abnormal CD4+ lymphocyte counts with HIV-2 infection was also significantly reduced. This natural history study demonstrates that HIV-2 has a reduced virulence compared to HIV-1.
Collapse
Affiliation(s)
- R Marlink
- Department of Cancer Biology, Harvard School of Public Health, Boston, MA 02115
| | | | | | | | | | | | | | | | | | | |
Collapse
|
4
|
Nair BC, Ford G, Kalyanaraman VS, Zafari M, Fang C, Sarngadharan MG. Enzyme immunoassay using native envelope glycoprotein (gp160) for detection of human immunodeficiency virus type 1 antibodies. J Clin Microbiol 1994; 32:1449-56. [PMID: 8077388 PMCID: PMC264018 DOI: 10.1128/jcm.32.6.1449-1456.1994] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
An enzyme immunoassay using the purified native gp160 for the detection of human immunodeficiency virus type 1 (HIV-1) antibody was developed. This assay was determined to be highly specific, since (i) 157 serum samples that were confirmed negative by Western blot (immunoblot) (WB) were negative, (ii) 41 serum samples from populations with medical conditions that might cause nonspecific assay reactivity were all negative, and (iii) all 15 serum samples that showed false-positive reactions in one or more commercial HIV-1 screening tests were negative. The assay gave 100% specificity with a randomly selected and unlinked panel of 1,000 serum samples from healthy blood donors. The sensitivity of the assay was assessed by testing 238 samples confirmed as HIV-1 antibody positive by a standardized WB assay. All 238 serum samples (100%) were reactive in the native gp160 assay. In a dilution panel of 14 weakly WB-positive serum samples, 7 samples reacted two-to fivefold more strongly in the gp160 assay than in a virus lysate-based assay; the remaining 7 samples gave comparable reactivities in the two tests. The reactivities of 13 of these 14 serum samples in the gp160 assay were higher than in a commercial enzyme immunoassay that uses a recombinant envelope protein as the antigen. The native gp160 assay was more sensitive to identify seroconversion. In a well-characterized panel of sequential blood samples from a seroconverter, the new assay detected antibodies at least one sample ahead of the other commercial assays tested.
Collapse
Affiliation(s)
- B C Nair
- Advanced BioScience Laboratories, Inc., Kensington, Maryland 20895
| | | | | | | | | | | |
Collapse
|
5
|
Morimoto M, Saitoh A, Ueba N, Nakata A, Shinagawa H. Use of the recombinant chimera proteins, LacZ-Env and Gag-Env, for immunological studies on HIV-1 infection. AIDS Res Hum Retroviruses 1993; 9:971-8. [PMID: 7506555 DOI: 10.1089/aid.1993.9.971] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
To use Env proteins as antigens for detection of the human immunodeficiency virus type-1 (HIV-1) antibodies, we attempted to overexpress the Env proteins in Escherichia coli. To study the epitopes in the Env proteins recognized by the sera of HIV carriers, various regions of the proviral DNA encoding the Env region were fused to the 3' end of the lacZ gene. The immunoblotting analysis of the LacZ-Env(512-611) and LacZ-Env(721-826) proteins with the 41 positive sera revealed that the former and the latter immunologically reacted with 100 and 78% of the sera, respectively. To avoid rare false-positive reactions due to the LacZ moiety of the fusion protein, we attempted to express the Env(512-611) alone or Gag-Env(512-611) under the control of bacteriophage T7 promoter. Although we could express only a low level of the Env(512-611) peptide in E. coli, we succeeded in producing large amounts of the Gag(121-406)-Env(512-611) and Gag(308-406)-Env(512-611) proteins as chimeric proteins. Both of these chimera proteins strongly reacted with the 41 positive sera. We purified these proteins and analyzed the immunological reactivity by dot blot with the 60 positive sera and the 84 normal sera. As little as 20 ng of the dotted proteins was enough for the reaction with the positive sera, whereas as much as 320 ng of them did not show false-positive reactions with the normal sera. We obtained highly purified Gag-Env proteins with highly specific seroreactivity, which should be useful for diagnosis and prognosis.
Collapse
Affiliation(s)
- M Morimoto
- Osaka Prefectural Institute of Public Health, Japan
| | | | | | | | | |
Collapse
|
6
|
Cunningham TP, Montelaro RC, Rushlow KE. Lentivirus envelope sequences and proviral genomes are stabilized in Escherichia coli when cloned in low-copy-number plasmid vectors. Gene 1993; 124:93-8. [PMID: 8382658 DOI: 10.1016/0378-1119(93)90766-v] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
A promoter-selection vector (pKK232-8) was used to identify sequences with strong Escherichia coli promoter activity positioned near the start of the envelope-encoding genes (env) of two lentiviruses, simian immunodeficiency virus (SIV) and equine infectious anemia virus (EIAV). For EIAV, cloning the cryptic promoter sequences together with downstream sequences encoding the envelope glycoprotein (gp90) in moderate- to high-copy-number (hcn) plasmid vectors, such as pBR322 or pUC, resulted in rearrangements and point mutations in env when propagated in E. coli. To alleviate this problem, low-copy-number (lcn) cloning vectors, pLG338-30 and pLG339-SPORT, were constructed. The plasmids carry resistance markers for ampicillin (ApR) or kanamycin (KmR), the pSC101 origin of replication (ori) from plasmid pLG338 [Stoker et al., Gene 18 (1982) 335-341], and a multiple cloning site (MCS) from plasmids pIBI30 or pSPORT. Full-length env and genomic proviral sequences of EIAV were genetically stable when subcloned into these lcn vectors. Proviral sequences of an SIV clone (pBK28-SIV) that are genetically unstable in the hcn vector pUC18 were also stabilized and remained fully infectious when subcloned into the lcn vector pLG339-SPORT. These lcn vectors appear to be generally useful in stabilizing lentivirus genomic sequences for subcloning, propagation, and manipulation in E. coli, possibly as a result of reducing the level of toxic gene expression from cryptic promoter sequences.
Collapse
Affiliation(s)
- T P Cunningham
- Department of Molecular Genetics and Biochemistry, University of Pittsburgh School of Medicine, PA 15261
| | | | | |
Collapse
|
7
|
Wu JY, Riggin CH, Seals JR, Murphy CI, Newman MJ. In vitro measurement of antigen-specific cell-mediated immune responses using recombinant HIV-1 proteins adsorbed to latex microspheres. J Immunol Methods 1991; 143:1-9. [PMID: 1717603 DOI: 10.1016/0022-1759(91)90266-i] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Recombinant proteins representing full-length and truncated forms of the human immunodeficiency virus type 1 envelope protein gp160 were produced in E. coli and sf9 insect cells. These proteins were denatured and reduced as a function of purification. We adsorbed these proteins onto latex microspheres and used the protein-coated particles as a vehicle to present the antigen in vitro to splenic mononuclear cells from immune mice. Recombinant proteins presented on the latex particles induced antigen-specific proliferative responses that were dependent on the antigen concentration. The proliferative responses were similar to those produced against an identical protein used in soluble form and equivalent protein concentrations. Latex microspheres coated with recombinant proteins could also induce precursor cytotoxic T lymphocytes to mature to functional effector cells in vitro. The use of the latex microspheres to present recombinant proteins as antigens allowed for the use of denatured proteins in our assay that were not soluble in aqueous solutions, such as cell culture media. This system of delivering recombinant proteins in vitro should greatly facilitate the use of recombinant proteins in assays involving live cells.
Collapse
Affiliation(s)
- J Y Wu
- Cambridge Biotech Corporation, Worcester, MA 01605
| | | | | | | | | |
Collapse
|
8
|
Huang ML, Essex M, Lee TH. Localization of immunogenic domains in the human immunodeficiency virus type 2 envelope. J Virol 1991; 65:5073-9. [PMID: 1714524 PMCID: PMC248972 DOI: 10.1128/jvi.65.9.5073-5079.1991] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Highly immunogenic domains have not yet been defined in the extracellular protein of the human immunodefiency virus type 2 (HIV-2) envelope. In this study, six contiguous segments covering the entire HIV-2ST envelope were amplified and cloned into a bacterial expression vector to localize the relative immunogenic reactivity of different regions of the molecule by Western blot (immunoblot) analysis. Our results demonstrate that the extracellular protein of the HIV-2 envelope contains highly immunogenic epitopes with potential value as type-specific markers for HIV-2 infection.
Collapse
Affiliation(s)
- M L Huang
- Department of Cancer Biology, Harvard School of Public Health, Boston, Massachusetts 02115
| | | | | |
Collapse
|
9
|
Madaule P, Gairin JE, Bénichou S, Rossier J. A peptide library expressed in yeast reveals new major epitopes from human immunodeficiency virus type 1. FEMS MICROBIOLOGY IMMUNOLOGY 1991; 3:99-107. [PMID: 1713777 DOI: 10.1111/j.1574-6968.1991.tb04203.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
In order to characterize novel human immunodeficiency virus type 1 (HIV-1) continuous epitopes, we designed a simple method, based on recombinant DNA, providing a complete set of peptides derived from HIV-1. A library (4 x 10(4) clones) was first constructed in a new expression/secretion vector, using as inserts small fragments of HIV-1 DNA (50-150 bp) generated by random DNAse I cleavage. This peptide library, expressed in the yeast Saccharomyces cerevisiae, was screened with sera of HIV-1 infected individuals and human and murine anti-HIV-1 monoclonal antibodies. Plasmids from immunoreactive colonies were recovered and the sequences of the HIV-1 derived inserts were determined. By using human sera, we have detected classical HIV-1 epitopes and identified two novel major epitopes, which may be used to improve diagnostic tests, localized in the p24 core protein and in the endonuclease. In addition, four minor epitopes were also defined by screening the library with monoclonal antibodies: in the protease, in the p17 core protein, in gp120 and near the C-terminal of gp41. This method is general and can be used for any protein from which a cloned cDNA is available.
Collapse
Affiliation(s)
- P Madaule
- Laboratoire de Physiologie Nerveuse, Centre National de la Recherche Scientifique, Gif-sur-Yvette, France
| | | | | | | |
Collapse
|
10
|
Chong YH, Ball JM, Issel CJ, Montelaro RC, Rushlow KE. Analysis of equine humoral immune responses to the transmembrane envelope glycoprotein (gp45) of equine infectious anemia virus. J Virol 1991; 65:1013-8. [PMID: 1846180 PMCID: PMC239850 DOI: 10.1128/jvi.65.2.1013-1018.1991] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Defined segments of the transmembrane envelope glycoprotein (gp45) of equine infectious anemia virus were expressed as TrpLE fusion proteins and examined for their reactivity in Western immunoblots against a diverse panel of equine immune sera. The most immunogenic region of gp45 was localized to its amino terminus, positioned between the hydrophobic fusion and the transmembrane domains. A series of overlapping synthetic peptides were used in enzyme-linked immunosorbent assays to define an immunodominant epitope within this region. In contrast, the carboxy-terminal half of gp45 displayed both weak and variable immunoreactivity with equine immune sera.
Collapse
Affiliation(s)
- Y H Chong
- Department of Molecular Genetics and Biochemistry, University of Pittsburgh School of Medicine, Pennsylvania 15261
| | | | | | | | | |
Collapse
|
11
|
Culp JS, Johansen H, Hellmig B, Beck J, Matthews TJ, Delers A, Rosenberg M. Regulated Expression Allows High Level Production and Secretion of HIV-1 gp120 Envelope Glycoprotein in Drosophila Schneider Cells. Nat Biotechnol 1991; 9:173-7. [PMID: 1369452 DOI: 10.1038/nbt0291-173] [Citation(s) in RCA: 64] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We have established a stable, continuous culture Drosophila Schneider 2 cell line that efficiently expresses a secreted, truncated form of the HIV envelope gp120 protein in a regulated manner. The Drosophila produced recombinant gp120 protein is highly glycosylated, is recognized by gp120-specific monoclonal antibodies, binds to the CD4 receptor and has the ability to inhibit syncytia formation between uninfected CD4+ cells and HIV infected cells. We conclude that this recombinant Drosophila envelope protein is an appropriate mimic of the authentic viral envelope protein. Thus, the Drosophila cell provides a continuous, stable culture system for the efficient expression of secreted forms of complex surface glycoproteins in quantities sufficient for detailed analyses.
Collapse
Affiliation(s)
- J S Culp
- Department of Protein Biochemistry, SmithKline Beecham Pharmaceuticals, King of Prussia, Pennsylvania 19406
| | | | | | | | | | | | | |
Collapse
|
12
|
Lillehoj EP, Alexander SS, Dubrule CJ, Wiktor S, Adams R, Tai CC, Manns A, Blattner WA. Development and evaluation of a human T-cell leukemia virus type I serologic confirmatory assay incorporating a recombinant envelope polypeptide. J Clin Microbiol 1990; 28:2653-8. [PMID: 2279997 PMCID: PMC268251 DOI: 10.1128/jcm.28.12.2653-2658.1990] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
A recombinant protein derived from the gp21 region of the human T-cell leukemia virus type I (HTLV-I) env gene was synthesized in Escherichia coli and purified by reversed-phase high-performance liquid chromatography. The purified protein was free of contaminating bacterial proteins and retained reactivity with human HTLV-I- and HTLV-II-positive sera and a gp21 monoclonal antibody. An immunoblot procedure using the recombinant polypeptide in conjunction with native viral proteins was more sensitive than the conventional immunoblot and radioimmunoprecipitation confirmatory assays for detection of antibodies to HTLV-I and HTLV-II env-encoded gene products. The recombinant protein was equally reactive with sera from polymerase chain reaction-confirmed HTLV-I or HTLV-II infections. Furthermore, on the basis of the differential reactivities of gp21-positive sera with the HTLV-I p19 and p24 gag-encoded proteins, an algorithm was proposed to distinguish exposure to HTLV-I from exposure to HTLV-II. These results establish the utility of a modified immunoblot assay incorporating a recombinant envelope polypeptide as an alternative to existing HTLV-I-confirmatory assays.
Collapse
Affiliation(s)
- E P Lillehoj
- Cambridge Biotech Corp., Rockville, Maryland 20850
| | | | | | | | | | | | | | | |
Collapse
|
13
|
Samuel KP, Ascione R, Kottaridis SD, Seth AK, Lautenberger JA, Zuber M, Strouboulis J, Papas TS. Expression of animal and human retroviral gene products in Escherichia coli with the lambda PL promoter pJL6 vector system. GENETIC ANALYSIS, TECHNIQUES AND APPLICATIONS 1990; 7:178-208. [PMID: 2150172 DOI: 10.1016/0735-0651(90)90023-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- K P Samuel
- Laboratory of Molecular Oncology, National Cancer Institute, Frederick, MD 21701-1013
| | | | | | | | | | | | | | | |
Collapse
|
14
|
Chemical synthesis and enzymatic assembly of fragments of the DNA coding immunodominant epitopes of human immunodeficiency virus. Chem Nat Compd 1990. [DOI: 10.1007/bf00597862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
15
|
Zuber M, Samuel KP, Lautenberger JA, Kanki PJ, Papas TS. Bacterially produced HIV-2 env polypeptides specific for distinguishing HIV-2 from HIV-1 infections. AIDS Res Hum Retroviruses 1990; 6:525-34. [PMID: 2187502 DOI: 10.1089/aid.1990.6.525] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Five unique recombinant polypeptides, each encoded by a DNA segment representing a different region of the HIV-2 (NIH-Z strain) env gene, were produced at relatively high levels (greater than or equal to 5%) as cII-fusion products in Escherichia coli. These recombinant polypeptides were characterized serologically by the Western blot assay against a panel of HIV-2 and HIV-1 antibody-positive sera, and with normal human sera (HIV-1 and HIV-2 antibody negative). Only those polypeptides that are encoded by a segment of the env gene from the N-terminal region of the transmembrane protein gp35 (amino acids 537 to 707) were immunoreactive. Three polypeptides (921, 996, and 997), each encoding this immunoreactive region of the HIV-2 (NIH-Z) gp35, reacted strongly and specifically with antibodies in sera from HIV-2-positive individuals, but not with antibodies in sera from HIV-1-positive or HIV-uninfected individuals. These results show that the N-terminal region of the HIV-2 gp35 contains a highly antigenic determinant which is strongly immunogenic in HIV-2-infected individuals. The gp35-encoded recombinant env polypeptides can potentially be used in diagnostic assays to specifically differentiate between HIV-2 and HIV-1 infections.
Collapse
Affiliation(s)
- M Zuber
- Program Resources, Inc., Frederick, MD
| | | | | | | | | |
Collapse
|
16
|
Mikhailov MV, Vasilyev AL, Nikolayeva IA, Arsenyan SG, Sverdlov ED. Antigenic determinants synthesized in a library of randomly cloned fragments of the HIV-1 genome. FEBS Lett 1990; 259:318-20. [PMID: 1688417 DOI: 10.1016/0014-5793(90)80036-i] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
A DNA expression library of randomly selected fragments of the HIV-1 genome was constructed and used to search for antigenic determinants. A large segment of the HIV-1 provirus was sonicated, and 150-250 bp DNA fragments were cloned in a system of expression vectors developed to obtain high yields of recombinant proteins in Escherichia coli. The expressed library was immunoscreened with sera of AIDS patients. Eleven identified immunoreactive clones were found to correspond to already known and new antigenic regions of HIV-1 proteins gp41, p24, and reverse transcriptase.
Collapse
Affiliation(s)
- M V Mikhailov
- M.M. Shemyakin Institute of Bioorganic Chemistry, USSR Academy of Sciences, Moscow
| | | | | | | | | |
Collapse
|
17
|
Payne SL, Rushlow K, Dhruva BR, Issel CJ, Montelaro RC. Localization of conserved and variable antigenic domains of equine infectious anemia virus envelope glycoproteins using recombinant env-encoded protein fragments produced in Escherichia coli. Virology 1989; 172:609-15. [PMID: 2552661 DOI: 10.1016/0042-6822(89)90203-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Previous characterizations of equine infectious anemia virus (EIAV) glycoprotein variation by DNA sequence analysis and epitope mapping using monoclonal antibodies (MAbs) have revealed the presence of conserved and variable regions within the EIAV env gene. To extend these studies, fragments of the EIAV envelope proteins gp90 and gp45 were expressed in Escherichia coli and used in Western blot analysis with a diverse panel of equine immune sera to identify antigenic segments. All sera from EIAV-infected animals reacted with the carboxyl terminal portion of gp90 and the amino terminal portion of gp45, indicating the highly conserved and immunodominant nature of these regions. Other gp90 segments, both from conserved and variable env sequences, displayed variable reactivities with the panel of equine sera. A panel of MAbs was also used in Western blot assays with the recombinant protein fragments for physical localization of previously identified MAb epitopes. The binding sites of two neutralizing MAbs were localized to a highly variable region of gp90, while nonneutralizing epitopes were localized to conserved and variable regions of the envelope glycoproteins. These results, in addition to localizing important antigenic sites on EIAV glycoproteins, indicate that previously defined conserved and variable env nucleotide sequences indeed encode protein sequences constituting conserved and variable immunogens during persistent infection by EIAV.
Collapse
Affiliation(s)
- S L Payne
- Department of Biochemistry, Louisiana State University, Baton Rouge
| | | | | | | | | |
Collapse
|
18
|
Zweig M, Bladen SV, Dubois GC, Samuel KP, Showalter SD, Papas TS. Comparative analysis of gp41 antigens by enzyme-linked immunosorbent assays for detecting antibodies to human immunodeficiency virus type 1. AIDS Res Hum Retroviruses 1988; 4:487-92. [PMID: 3265329 DOI: 10.1089/aid.1988.4.487] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
We have compared the antigenic qualities of human immunodeficiency virus type 1 (HIV-1) gp41 glycoprotein with a synthetic oligopeptide (peptide R21S) and a bacterially synthesized protein (protein 566), which are homologous with the N-terminal region of gp41, in enzyme-linked immunosorbent assays (ELISA) for detecting antibodies to HIV-1 in sera of patients with the acquired immunodeficiency syndrome (AIDS) or the aids-related complex (ARC). Although the use of all three types of antigens readily allowed the detection of antibodies in human sera, ELISA employing purified gp41 glycoprotein and the protein 566 were more specific and sensitive than the peptide R21S ELISA.
Collapse
Affiliation(s)
- M Zweig
- Program Resources, Inc., National Cancer Institute-Frederick Cancer Research Facility, MD
| | | | | | | | | | | |
Collapse
|