Chemistry: molecular biology and microbiology – Measuring or testing process involving enzymes or... – Involving antigen-antibody binding – specific binding protein...
Reexamination Certificate
1994-09-02
2001-12-04
Saunders, David (Department: 1644)
Chemistry: molecular biology and microbiology
Measuring or testing process involving enzymes or...
Involving antigen-antibody binding, specific binding protein...
C435S007900, C435S007940, C435S018000, C435S021000, C435S026000, C435S028000, C435S975000, C436S507000, C436S512000, C436S518000, C436S536000, C436S537000, C436S547000, C436S548000, C436S800000, C436S804000, C436S805000, C436S808000, C436S815000, C436S817000, C530S388900, C530S389800, C530S391300, C530S808000
Reexamination Certificate
active
06326159
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
There is a continuing and increasing need for accurate, sensitive techniques for measuring trace amounts of organic materials in a wide variety of samples. This need includes the measurement of drugs, naturally occurring physiological active compounds or nutrients in physiological fluids, the presence of trace amounts of contaminants or toxic materials in foods, water or other fluids, and the like, as well as monitoring materials for trace contamination introduced during chemical processing.
Among the various techniques which have found increasing exploitation are techniques involving receptors which recognize or bind to a specific polar and spatial organization of one or more molecules. For the most part, the receptors are antibodies and the techniques are referred to as immunoassays. These techniques conventionally employ a labelled ligand, where the binding to the receptor allows for distinguishing between a bound labelled ligand and an unbound labelled ligand. Certain techniques, generally referred to as heterogeneous, rely on segregating the bound from the unbound labelled ligand. Other techniques, generally referred as homogeneous, rely on the bound labelled ligand providing a signal level different from unbound labelled ligand.
Methods are known for the detection of polyvalent antigens wherein at least two different binding sites on the antigen are used. Two-site immunometric assays are well known. They are used to detect the presence or concentration of a multideterminant antigen in a liquid sample. They involve reacting the antigen with both an immobilized antibody directed against one of the antigenic determinants and an antibody that is directed against another of the antigenic determinants and is indirectly or directly labelled to permit detection of the resulting immune complex. It is also known to use polyclonal antibodies, monoclonal antibodies, or a combination of both polyclonal and monoclonal antibodies. The use of two antibodies in the immunoassay enhances the sensitivity of the assay by permitting the use of excess antibody to ensure complete binding of antibody to all of the analyte in the sample. The use of monoclonal antibodies in a two-site immunoassay in some cases also increases the specificity of the assay by requiring the presence of two epitopic sites on the same molecule to produce a positive result.
While such assays involving two antibodies are useful where the analyte is a polyvalent antigen, the benefits realized by employing two antibodies are not available for monoepitopic antigens such as drugs or other organic compounds.
2. Description of the Related Art
The use of double antibodies for enhanced sensitivity in immunoassays is described in U.S. Pat. No. 4,281,061. Two-site immunoassays using monoclonal antibodies of different classes or subclasses and test kits for performing such assays are disclosed in U.S. Pat. No. 4,474,892. A method for the detection and/or determination of a polyvalent antigen using at least two different monoclonal antibodies is described in U.S. Pat. No. 4, 471,058. U.S. Pat. No. 4,486,530 discloses immunometric assays using monoclonal antibodies. Monoclonal antibody mixtures and their use for enhanced sensitivity in immunoassays is discussed in U.S. Pat. No. 4,514,505. The use of anti-idiotype antibodies in immunoassays is discussed in U.S. Pat. No. 4,536,479. U.S. Pat. No. 4,062,935 discloses an immunoassay involving the binding of RF to the antigen-antibody complex. Sensitive immunoassays of antigens or antibodies sequestered within immune complexes is disclosed in U.S. Pat. No. 4,459,359. An assay of immune complexes is discussed in U.S. Pat. No. 4,141,965. U.S. Pat. No. 4,420,461 discloses aggulination-inhibition test kits for detecting immune complexes. An enhancing antibody being a novel component of the immune response is described by Nemazee, et al.,
Proc. Natl. Acad. Sci., USA
, 79:3828-3832 (1982).
SUMMARY OF THE INVENTION
Compositions and methods are provided for conducting an immunoassay. One aspect of the present invention includes antibodies exhibiting a binding affinity for an immune complex of a monoepitopic antigen and an antibody for such antigen that is substantially greater than the binding affinity for the monoepitopic antigen or the antibody for the antigen apart from the immune complex. Normally, the monoepitopic antigen has a molecular weight: of less than about 1500 and the antibody is a monoclonal antibody. The antibodies of the invention can be bound to a label for use in immunoassays.
Another aspect of the invention includes compositions comprising an immune sandwich complex of a monoepitopic antigen or analog thereof, a first antibody that binds to the monoepitopic antigen, and a second antibody that exhibits a binding affinity for an immune complex of the monoepitopic antigen or analog thereof and a first antibody that is substantially greater than the binding affinity for the monoepitopic antigen or the first antibody apart from the immune complex.
Another aspect of the invention includes methods for preparing an antibody that binds to an immune complex of a monoepitopic antigen and a first antibody. In the methods animals are immunized with the first antibody affinity labeled with its complementary antigen.
Another aspect of the present invention includes methods for determining a monoepitopic antigen in a sample suspected of containing the antigen. The method comprises forming an immune sandwich complex comprising the monbepitopic antigen or analog thereof, a first antibody that binds to the monoepitopic antigen, and a second antibody that exhibits a binding affinity for the immune complex of the monoepitopic antigen and the first antibody that is substantially greater than the binding affinity for the monoepitopic antigen or the first antibody apart from the immune complex. The immune sandwich complex is then detected, the presence of said complex being related to the amount of monoepitopic antigen in the sample.
Another aspect of the present invention concerns improvements in homogeneous assays for the determination of a monoepitopic antigen in a sample suspected of containing such antigen. Such homogeneous assays normally comprise the steps of (a) combining in an aqueous medium the sample, labelled monoepitopic antigen, and a first antibody that binds to the monoepitopfc antigen and (b) determining the effect of the sample on the amount of labelled monoepitopic antigen that binds to the first antibody. The improvement of the present invention comprises adding to the aqueous medium a second antibody that exhibits a binding affinity for the immune complex of the monoepitopic antigen and the first antibody that is substantially greater than the binding affinity for the monoepitopic antigen or the first antibody apart from the immune complex.
The invention further includes kits for use in conducting an assay for analyte in a sample suspected of containing the analyte. The kit comprises in packaged combination an antibody that exhibits a binding affinity for an immune complex of a monoepitopic antigen and an antibody for such antigen that is substantially greater than the binding affinity for the monoepitopic antigen or the antibody for the antigen apart from the immune complex.
REFERENCES:
patent: 4062935 (1977-12-01), Mason et al.
patent: 4141965 (1979-02-01), Soothill et al.
patent: 4281061 (1981-07-01), Zuk et al.
patent: 4420461 (1983-12-01), Reckel et al.
patent: 4459359 (1984-07-01), Neurath
patent: 4471058 (1984-09-01), Smith et al.
patent: 4474892 (1984-10-01), Murad et al.
patent: 4486530 (1984-12-01), David et al.
patent: 4514505 (1985-04-01), Canfield et al.
patent: 4536479 (1985-08-01), Vander-Mallie
patent: 4544640 (1985-10-01), Soma et al.
patent: 4670383 (1987-06-01), Baier et al.
patent: 4828985 (1989-05-01), Self
patent: 4840895 (1989-06-01), Self
patent: 0 027 567 A1 (1981-04-01), None
patent: 0 174 652 A3 (1986-03-01), None
patent: 2161165 (1986-01-01), None
patent: 2 171 999 A (1986-09-01), None
patent: 217
Jelesko John
Kempe Thomas D.
Pirio Marcel R.
Ullman Edwin F.
Dade Behring Marburg GmbH
Leitereg Theodore J
Saunders David
LandOfFree
Receptors for immune complexes does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Receptors for immune complexes, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Receptors for immune complexes will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2566660