Suitable Monoclonal Antibodies Research Articles

Human IgG subclass assays using a novel assay method

To facilitate assays for human IgG subclasses, we have adapted a novel assay method (particle concentration fluorescence immunoassay) (Jolley et al., 1984; MacCrindle et al., 1985) using one polyclonal and several monoclonal antibodies for human IgG subclasses. The advantages of this new assay over previously described methods are sensitivity (0.3–3 μg/ml), and autmated measurement of multiple samples in a short time (2 h). We found that a monkey antibody for IgG2 and monoclonal antibodies for IgG1, IgG4b epitope, and IgG3 can be adapted to this method. We evaluated 7 different antibodies to IgG4 without finding a suitable monoclonal antibody for this assay method. Several of these IgG4 hybridoma antibodies, however, could be used in a competitive radioimmunoassay using polyvinyl microtiter plates. The usefulness of a monoclonal antibody to the IgG4b epitope was evaluated because no suitable monoclonal antibodies for IgG2 are available. Because IgG4 levels are usually much smaller than IgG2 levels, and the IgG4b epitope is expressed on all IgG2 alleles and only some IgG4 alleles (Kunkel et al., 1970), the antibody for IgG4b is potentially useful to screen a large number of samples for IgG2 deficiency. However, when the monoclonal antibody for IgG4b was compared with an IgG2 specific antibody produced in a monkey, the IgG4b antibody could identify only about half of the patients with known IgG2 deficiency.

Monoclonal antibodies to rat B lymphocyte (sub-)populations.

The study of B lymphocyte differentiation is greatly facilitated by the use of suitable monoclonal antibodies (MAb’s). For mice and men a variety of MAb’s binding to cell surface determinants of B lineage cells has been described (1). However, as yet almost no B lineage specific MAb’s have been described for the rat. Since this animal appears very appropiate for studies of early phases of B lymphocyte differentiation (2) as well as late phases, in particular with respect to marginal zone cells (3), we produced MAb’s against surface antigens of rat B lineage cells.

76] A rapid quantitative assay of high sensitivity for human leukocyte interferon with monoclonal antibodies

Publisher Summary This chapter describes the use of two monoclonal antibodies in a simple and rapid solid phase sandwich immunoassay for the detection and quantitative determination of human leukocyte interferon. Monoclonal antibodies provide a novel opportunity to select two or more antibodies directed against different epitopes of an antigen. For a sandwich immunoassay, these antibodies should have the following properties: (1) lack of mutual interference with antigen binding, (2) optimal characteristics for solid phase function, that is, antigen collection, (3) suitability for revealing antigen, that is, stability to labeling with radioisotope, enzyme, fluorescent dye, and such, and (4) high antigen affinity and specificity of both antibodies. The use and proper selection of two suitable monoclonal antibodies for measuring an antigen in a sandwich immunoassay provides a novel and universal strategy for designing and developing this type of assay for any antigen that has at least two independent epitopes. For some antigens, this approach may be the only possible solution; for other large substances such as carcinoembryonic antigen it should improve the specificity, sensitivity, and long-term reproducibility of already existing sandwich immunoassays. This interferon radioimmunoassay has already proven extremely useful for monitoring interferon during purification.