# US 8,785,596 B2 · Antigen constructs useful in the detection and differentiation of antibodies to HIV > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,785,596 B2 - Document ID: US8785596B2 - Status: Granted - Kind: B2 - Application number: 12/973,384 - Filed: 2010-12-20 - Published: 2011-04-21 - Granted: 2014-07-22 - Earliest claimed: 1997-08-15 - Assignees: Abbott Laboratories - Applicants: John R. Hackett, Jr.; Julie Yamaguchi; Alan M. Golden; Catherine A. Brennan; Robert K. Hickman; Sushil G. Devare - Inventors: John R. Hackett, Jr.; Julie Yamaguchi; Alan M. Golden; Catherine A. Brennan; Robert K. Hickman; Sushil G. Devare - Web page: https://patentgrep.com/patent/US8785596B2 ## CPC - C07K 14/005: from viruses - A61P 31/18: for HIV - A61K 39/00: Medicinal preparations containing antigens or antibodies (materials for immunoassay G01N33/53) - C07K 2319/00: Fusion polypeptide - C12N 2740/16122: New viral proteins or individual genes, new structural or functional aspects of known viral proteins or genes - G01N 2333/162: env, e.g. gp160, gp110/120, gp41, V3, peptid T, DC4-Binding site - C07K: PEPTIDES (peptides in foodstuffs A23; obtaining protein compositions for foodstuffs, working-up proteins for foodstuffs A23J; preparations for medicinal purposes A61K; peptides containing beta-lactam rings C07D; cyclic dipeptides not having in their molecule any other peptide link than those which form their ring, e.g. piperazine-2,5-diones, C07D; ergot alkaloids of the cyclic peptide type C07D519/02; macromolecular compounds having statistically distributed amino acid units in their molecules, i.e. when the preparation does not provide for a specific; but for a random sequence of the amino acid units, homopolyamides and block copolyamides derived from amino acids C08G69/00; macromolecular products derived from proteins C08H1/00; preparation of glue or gelatine C09H; single cell proteins, enzymes C12N; genetic engineering processes for obtaining peptides C12N15/00; compositions for measuring or testing processes involving enzymes C12Q; investigation or analysis of biological material G01N33/00) - A61P: SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS - A61K: PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES (devices or methods specially adapted for bringing pharmaceutical products into particular physical or administering forms A61J3/00; chemical aspects of, or use of materials for deodorisation of air, for disinfection or sterilisation, or for bandages, dressings, absorbent pads or surgical articles A61L; soap compositions C11D) - C12N: MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA (microbiological testing media C12Q1/00) - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) ## Abstract Isolated HIV-1 Group O env polypeptides obtained from the HIV-1 isolate HAM112 are claimed, as well as (a) antigen constructs comprising fusions of one or more of each of HIV-1 Group O env polypeptides and HIV-1 Group M env polypeptide and (b) further antigen constructs containing additional Group O sequences and especially the gp41 IDR of isolate HAM112. Also claimed are polynucleotide sequences encoding the above, expression vectors comprising the same, host cells transformed thereby, and immunoassay methods and kits utilizing the antigen constructs of the invention. ## Claims ### Claim 1 An isolated antigen construct, wherein the antigen construct comprises a fusion protein, the fusion protein comprising a first HIV-2 gp120 env polypeptide fused to a second HIV-2 gp36 env polypeptide, wherein the first polypeptide comprises amino acid residues 248 through 307 of SEQ ID NO: 55 and the second polypeptide comprises amino acids 308 through 466 of SEQ ID NO: 55. ### Claim 2 (depends on 1) The antigen construct according to claim 1, wherein: (a) the first HIV-2 env gp120 polypeptide consists of residues 248 through 307 of SEQ ID NO: 55 and (b) the second HIV-2 env gp36 polypeptide consists of residues 308 through 466 of SEQ ID NO: 55. ### Claim 3 (depends on 1, 2) A plasmid comprising a polynucleotide encoding an antigen-construct of claim 1 or 2. ### Claim 4 (depends on 3) An isolated host cell transformed by the plasmid according to claim 3. ### Claim 5 (depends on 4) The isolated host cell according to claim 4 wherein the host is Escherichia coli. ### Claim 6 (depends on 1, 2) A method for detecting antibodies to HIV-2 in a test sample comprising the steps of: (a) combining at least one antigen construct of claim 1 or 2 with the test sample to form a mixture; (b) incubating the mixture under conditions suitable for formation of complexes between the antigen and antibodies, if any, which are present in the sample and are immunologically reactive with the antigen; and (c) detecting the presence of any complexes formed. ### Claim 7 (depends on 1, 2, 6) The method according to claim 6 wherein detecting the presence of complexes in step (c) is carried out using an additional antigen construct of claim 1 or 2 to which is attached a signal generating compound. ### Claim 8 (depends on 1, 2, 6) The method according to claim 6 wherein detecting the presence of complexes in step (c) is carried out using an additional antigen construct of claim 1 or 2 to which is attached a first member of a specific binding partner, and further using an indicator reagent comprising a second member of the specific binding pair to which is attached a signal-generating compound. ### Claim 9 (depends on 6) The method according to claim 6 wherein detecting the presence of complexes in step (c) is carried out using an antibody directed to the complexes formed in step (b) to which is attached a signal-generating compound. ### Claim 10 (depends on 6) The method according to claim 6 wherein detecting the presence of complexes in step (c) is carried out using an antibody directed to the complexes formed in step (b) to which is attached a first member of a specific binding partner, and further using an indicator reagent comprising a second member of the specific binding pair to which is attached a signal-generating compound. ### Claim 11 (depends on 1, 2) An immunoassay kit for the detection of antibodies for HIV-2 comprising an antigen construct of claim 1 or 2. ### Claim 12 (depends on 11) The immunoassay kit according to claim 11 wherein the antigen construct is a capture reagent. ### Claim 13 (depends on 11) The immunoassay kit according to claim 11 wherein the antigen construct is an indicator reagent. ### Claim 14 (depends on 11) The immunoassay kit according to claim 11 wherein the antigen construct is attached to a first member of a specific binding pair, the kit additionally comprising an indicator reagent comprising a second member of the specific binding pair attached to a signal-generating compound.