# US 5,705,331 A · HIV nucleocapsid protein capture assay and method of use > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,705,331 A - Document ID: US5705331A - Status: Granted - Kind: A - Application number: 08/485,833 - Filed: 1995-06-07 - Granted: 1998-01-06 - Earliest claimed: 1992-10-28 - Assignees: The United States of America, as represented by the Secretary, Department of Health and Human Services - Inventors: Larry O. Arthur; Louis E. Henderson - Web page: https://patentgrep.com/patent/US5705331A ## CPC - C07K 14/005: from viruses - C07K 16/1143: {Gag-pol proteins, e.g. p17or p24} - G01N 33/56988: {HIV or HTLV} - C12N 2740/16222: New viral proteins or individual genes, new structural or functional aspects of known viral proteins or genes - G01N 2800/52: Predicting or monitoring the response to treatment, e.g. for selection of therapy based on assay results in personalised medicine; Prognosis - Y10S 435/971: Capture of complex after antigen-antibody reaction - Y10S 435/974: Aids related test - Y10S 435/975: Kit - 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) - 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) - C12N: MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA (microbiological testing media C12Q1/00) - Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS ## Abstract An antigen capture method, and an antigen capture assay diagnostic kit, for detecting the presence or concentration of HIV in a biological sample without interference from antigen-antibody immune complexes is provided. The lysate of a biological sample obtained from an animal is contacted with a detectable mount of an antibody specifically reactive with the nucleocapsid p7 antigen or an immunoreactive fragment of the p7 antigen for a time and under conditions sufficient for p7 antigen contained in the lysate to form a p7-antibody complex. The presence or concentration of this p7-antibody complex is determined to detect or quantitate the presence of HIV in the biological sample. Uses of this assay and method include detecting the presence of HIV infection in an infant born to an HIV-infected mother, monitoring the progression of HIV infection, and evaluating the effectiveness of an anti-HIV treatment administered to an animal, such as a human. Purified antibodies specifically reactive with an immunoreactive epitope specific to p7 or an immunoreactive fragment of p7 are also provided as well as an antigen capture method for detecting the presence of a lentivirus in a biological sample involving the nucleocapsid protein of the lentivirus. ## Claims ### Claim 1 An antigen capture method for detecting the presence of a lentivirus in a biological sample, comprising the steps of: a) contacting a lysate of the biological sample with a detectable amount of an antibody specifically reactive with the nucleocapsid protein of the lentivirus or with an immunoreactive fragment of the nucleocapsid protein for a time and under conditions sufficient for nucleocapsid protein contained in the lysate to form a nucleocapsid protein-antibody complex; and b) determining the presence of the nucleocapsid protein-antibody complex, thereby detecting the presence of the lentivirus in the biological sample. ### Claim 2 (depends on 1) The antigen capture method of claim 1, wherein the lentivirus is selected from the group consisting of HIV-1, HIV-2, SIV, bovine immunodeficiency virus, feline immunodeficiency virus, equine infectious anemia virus, caprine arthritis encephalitis virus and visna virus. ### Claim 3 A purified antibody specifically reactive with an immunoreactive epitope specific to a nucleocapsid protein of a lentivirus or with an immunoreactive fragment of the nucleocapsid protein of a lentivirus. ### Claim 4 (depends on 1) The method of claim 1, further comprising quantitating the amount of nucleocapsid protein-antibody complex to determine the extent of lentivirus viremia in the biological sample. ### Claim 5 (depends on 1) The method of claim 1, wherein the antibody specifically reactive with the nucleocapsid protein antigen or with an immunoreactive fragment of the nucleocapsid protein antigen is immobilized and the determining step comprises the steps of: a. removing excess antibody that is not bound to nucleocapsid protein; b. contacting the nucleocapsid protein-antibody complex with a secondary antibody that is labeled with a detectable moiety, wherein the secondary antibody is capable of binding with the nucleocapsid protein-antibody complex; and c. measuring the presence of the secondary antibody bound to the nucleocapsid protein-antibody complex to detect the presence of lentivirus in the biological sample. ### Claim 6 (depends on 5) The method of claim 5, further comprising quantitating the amount of secondary antibody bound to the nucleocapsid protein-antibody complex to determine the extent of lentivirus viremia in the biological sample. ### Claim 7 (depends on 1) The method of claim 1, wherein the biological sample is selected from the group consisting of a bodily fluid, tissue, or cell culture fluid. ### Claim 8 (depends on 1) The method of claim 1, wherein the biological sample is selected from the group consisting of blood, serum, plasma, saliva and urine. ### Claim 9 (depends on 3) The antibody of claim 3, wherein the antibody is labeled with a detectable moiety. ### Claim 10 (depends on 3) The antibody of claim 3, wherein the antibody is bound to a solid support. ### Claim 11 A method for monitoring the level of lentivirus viremia progression of lentivirus infection in an animal, comprising the steps of: a. at a multiplicity of times spaced over a period of time, obtaining a biological sample from an animal; b. for each biological sample, contacting a lysate of the biological sample with a detectable amount of an antibody specifically reactive with a lentivirus nucleocapsid protein antigen or with an immunoreactive fragment of a lentivirus nucleocapsid protein antigen for a time and under conditions sufficient for the nucleocapsid protein antigen contained in the lysate to form a nucleocapsid protein-antibody complex; c. determining the concentration of the nucleocapsid protein-antibody complex in the lysate, thereby determining the concentration of nucleocapsid protein in the biological sample; and d. comparing the concentration of nucleocapsid protein in the biological samples obtained over the period of time, wherein an increase of the concentration of nucleocapsid protein over the period of time correlates with increased level of lentivirus viremia and a decrease of the concentration of nucleocapsid protein over the period of time correlates with decreased level of lentivirus viremia. ### Claim 12 An antigen capture assay diagnostic kit for the detection of the presence or amount of a lentivirus nucleocapsid protein, comprising: a. an antibody specifically reactive with a lentivirus nucleocapsid protein antigen or with an immunoreactive fragment of a lentivirus nucleocapsid protein antigen; and b. means for detecting the formation of immune complexes between the nucleocapsid protein and the antibody specifically reactive with the nucleocapsid protein antigen or an immunoreactive fragment of the nucleocapsid protein antigen. ### Claim 13 (depends on 12) The diagnostic kit of claim 12, wherein the means for detecting the formation of the immune complexes comprise a reagent for ascertaining the presence of an antibody labeled with a detectable moiety.