Antibody screening assays

More recently, the National Institute of Environmental Health Sciences and the National Institute for Occupational Safety and Health convened a workshop in which experts in the field of developmental immunotoxicology developed a tiered approach for assaying the developmental immunotoxicity of chemicals.18 The recommended assays were separated into three groups (1) an initial set of screening assays, (2) assays for validation of a correlation between the assay end point and functional outcomes in humans, and (3) assays for research development.18 The initial screening assays included analysis of the primary antibody response to a T-dependent antigen, the delayed type... 

Patients and blood donors are routinely screened for exposure to HIV by means of ElISA and Western blot assays of blood samples (F uie 1-7-15). The assays are designed to detect antibodies to HIV in the blood of the test subject The ELISA is used as the primary screening assay because it is very sensitive. Because the reference interval for the test is set to include everyone with antibodies to HIV, it also gives false positives and thus has a rather low positive predictive value, especially in low-risk populations. The Western blot (or immunoblot) is used as the confirmatory test for HIV exposure. In the Western blot technique, specific HIV proteins are separated by gel electrophoresis and blotted to a filter. The filter is incubated with the test sample. If the sample contains antibodies to HIV, they will bind to the proteins on the filter. The filter is next washed and incubated with a labeled goat anti-human IgG to visualize any bound human antibodies. The Western blot is highly specific. The combination of an ELISA and Western blot has a positive predictive value of greater than 99%,... 

It is preferable to use NS-0 as a fusion partner, it does not secrete a constitutive antibody but has the ability to produce monoclonal antibodies once fused to an immune spleen cell. NS-1 has a constitutive antibody, which may cause interference in screening assays for recombinant hybridoma cells. 

Catalytic antibodies were first reported in 1986 by Lerner and Schultz for the hydrolysis of simple esters. Since then over 100 different reactions have been catalyzed by antibodies, from enantioselective preparative reactions to prodrug activations in vivo [1]. New methods have been developed, including specific immunization protocols, direct screening assays for catalysis, and manipulations with recombinant antibodies via phage display. This article gives an overview of work done towards applying catalytic antibodies for synthetic organic reactions by our and other laboratories. 

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