Biomaterial Database

Enzyme-linked immunoassay for human immunodeficiency virus type 1 envelope glycoprotein 120. 1991

M Gilbert, and J Kirihara, and J Mills

Division of Infectious Diseases, San Francisco General Hospital, California 94110-2897.

An enzyme-linked immunosorbent assay (ELISA) that can measure picogram quantities of human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein 120 (gp120) in cell culture medium or body fluids has been developed. Recombinant, soluble CD4 immobilized in microtiter trays was used to capture gp120, which was then detected with polyclonal sheep antibody to gp120 followed by biotinylated rabbit anti-sheep immunoglobulin G and an avidin-alkaline phosphatase indicator system. With a reference recombinant gp120, the assay showed a linear relationship between optical density and concentrations ranging from 60 to 6,000 pg/100-microliters well; precision of the assay varied with the concentrations and ranged from +/- 40% with amounts smaller than 200 pg to +/- 10% with amounts larger than 200 pg. In a group of coded samples containing 60 pg (approximately 10(7) molecules) of reference gp120, the assay correctly identified the samples as containing gp120 99% of the time, with no false-positive results recorded for blank samples. Recombinant gp120 prepared in another cell culture system demonstrated a binding coefficient 13-fold lower than that of reference gp120. Mixing standard amounts of reference gp120 with increasing concentrations of human sera reduced assay sensitivity, although the linear relationship between gp120 concentration and optical density remained. With this assay we were able to detect gp120 in HIV-1 suspensions prepared from cultured lymphoblastoid cells and in the sera of HIV-1-infected patients. This ELISA for gp120 should be useful for studying the biological role of gp120 in HIV infection.

UI	MeSH Term	Description	Entries
D008214	Lymphocytes	White blood cells formed in the body's lymphoid tissue. The nucleus is round or ovoid with coarse, irregularly clumped chromatin while the cytoplasm is typically pale blue with azurophilic (if any) granules. Most lymphocytes can be classified as either T or B (with subpopulations of each), or NATURAL KILLER CELLS.	Lymphoid Cells,Cell, Lymphoid,Cells, Lymphoid,Lymphocyte,Lymphoid Cell
D011994	Recombinant Proteins	Proteins prepared by recombinant DNA technology.	Biosynthetic Protein,Biosynthetic Proteins,DNA Recombinant Proteins,Recombinant Protein,Proteins, Biosynthetic,Proteins, Recombinant DNA,DNA Proteins, Recombinant,Protein, Biosynthetic,Protein, Recombinant,Proteins, DNA Recombinant,Proteins, Recombinant,Recombinant DNA Proteins,Recombinant Proteins, DNA
D004797	Enzyme-Linked Immunosorbent Assay	An immunoassay utilizing an antibody labeled with an enzyme marker such as horseradish peroxidase. While either the enzyme or the antibody is bound to an immunosorbent substrate, they both retain their biologic activity; the change in enzyme activity as a result of the enzyme-antibody-antigen reaction is proportional to the concentration of the antigen and can be measured spectrophotometrically or with the naked eye. Many variations of the method have been developed.	ELISA,Assay, Enzyme-Linked Immunosorbent,Assays, Enzyme-Linked Immunosorbent,Enzyme Linked Immunosorbent Assay,Enzyme-Linked Immunosorbent Assays,Immunosorbent Assay, Enzyme-Linked,Immunosorbent Assays, Enzyme-Linked
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D012680	Sensitivity and Specificity	Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)	Specificity,Sensitivity,Specificity and Sensitivity
D012995	Solubility	The ability of a substance to be dissolved, i.e. to form a solution with another substance. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Solubilities
D015497	HIV-1	The type species of LENTIVIRUS and the etiologic agent of AIDS. It is characterized by its cytopathic effect and affinity for the T4-lymphocyte.	Human immunodeficiency virus 1,HIV-I,Human Immunodeficiency Virus Type 1,Immunodeficiency Virus Type 1, Human
D015699	HIV Envelope Protein gp120	External envelope protein of the human immunodeficiency virus which is encoded by the HIV env gene. It has a molecular weight of 120 kDa and contains numerous glycosylation sites. Gp120 binds to cells expressing CD4 cell-surface antigens, most notably T4-lymphocytes and monocytes/macrophages. Gp120 has been shown to interfere with the normal function of CD4 and is at least partly responsible for the cytopathic effect of HIV.	Envelope Glycoprotein gp120, HIV,HTLV-III gp120,env Protein gp120, HIV,gp120(HIV),HIV Envelope Glycoprotein gp120,gp120 Envelope Glycoprotein, HIV,HTLV III gp120,gp120, HTLV-III
D015704	CD4 Antigens	55-kDa antigens found on HELPER-INDUCER T-LYMPHOCYTES and on a variety of other immune cell types. They are members of the immunoglobulin supergene family and are implicated as associative recognition elements in MAJOR HISTOCOMPATIBILITY COMPLEX class II-restricted immune responses. On T-lymphocytes they define the helper/inducer subset. T4 antigens also serve as INTERLEUKIN-15 receptors and bind to the HIV receptors, binding directly to the HIV ENVELOPE PROTEIN GP120.	Antigens, CD4,CD4 Molecule,CD4 Receptor,CD4 Receptors,Receptors, CD4,T4 Antigens, T-Cell,CD4 Antigen,Receptors, Surface CD4,Surface CD4 Receptor,Antigen, CD4,Antigens, T-Cell T4,CD4 Receptor, Surface,CD4 Receptors, Surface,Receptor, CD4,Surface CD4 Receptors,T-Cell T4 Antigens,T4 Antigens, T Cell