Measurement with polyclonal

Vandenbroeck et al.7 used an ELISA to determine the recovery of immu-noreactive porcine interferon-gamma (IFN-y) from E. coli inclusion bodies. The ELISA used a polyclonal coating antibody with detection by a MAb. The inclusion bodies were solubilized in diluted 6 M guanidine/HCl and IFN subsequently refolded by its removal. The antiviral activity of the interferon was measured with a bioassay using the cytopathic effect (CPE) of vesicular stomatitis virus (VSV) on bovine kidney cells. The results of this study showed that the immu-noreactivity measured by ELISA matched the biological activity measured by bioassay. 

R. S., Synthetic peptide vaccine development measurement of polyclonal antibody affinity and cross-reactivity using a new peptide capture and release system for surface plasmon resonance spectroscopy, J. Mol. Recog. 17, 540-557, 2004 Stills, H.F, Jr., Adjuvants and antibody production dispelling the myths associated with Freund s complete and other adjuvants, ILAR J. 46, 280-293, 2005 Miller, L.H., Saul, A., and Mahanty,... 

Immunological methods with polyclonal antisera or monoclonal antibodies provide the best quantitative measurements of intestinal or placental ALPs. Much more difficult is the production of antibodies that selectively react with different products of the tissue-nonspecific ALP gene, including the liver- and bone-derived isoforms, as these antibodies should recognize specific sugar side chains instead of... 

Beta-endorphin is a frequently measured opioid peptide. Immunoassay is the method of choice for the analysis of plasma (3-endorphin. Both RIAs and direct IRMAs have been developed for this purpose. Commercial reagent kits are widely available, and many commercial reference laboratories offer P-endorphin assays. The concentrations of P-endorphin are usually very low to undetectable in normal subjects, and it may be necessary to use extraction procedures to detect meaningful concentrations in plasma. The specificity of commercial antibodies for p-endorphin relative to p-LPH varies widely in some immunoassays, 50% cross-reactivity is seen with p-LPH. With polyclonal antibodies, results may be spuriously high owing to crossreactivity with serum immunoglobulin G (e.g., in patients with immunoglobulin G myeloma). 

Figure 1 shows the principles of the ELISA used. The basis of the test is the prevention of pretitrated monoclonal antibody (mAb) from binding to rinderpest antigen on the wells of a microtiter plate hy polyclonal antibodies in samples (serum). The degree of prevention is measured with reference to controls with no sample added (Cm) in which maximum optical density (OD) values are observed, and to wells in which is only conjugate is added (Cc) where low color is observed. Percentage inhibition (PI%) values are calculated with reference to these values. 

Thylakoid proteins were solubilized in Li dodecyl sulfate, separated on 10-20% gradient polyacrylamide gels and detected by polyclonal antibodies as described in (12,13). Measurements of fluorescence kinetics at room temperature were as described in (13). Fluorescence spectra at 77°K were determined on a Spex Fluorolog spectrofluorometer as described in (12). Oxygen evolution from whole cells was measured with a Clark-... 

Mitogenic effects of endotoxin free substances were screened with the lymphocyte transformation test. In this test the rate of lymphocyte proliferation was quantified by determination of the incorporation of [ H]-thymidine into the DNA of human lymphocytes. Stimulation of lymphocytes was measured with or without coincubation of lectins as mitogens such as concanavalin A (ConA) and phytohemagglutinin (PHA). Saponins such as crude Quillaja saponins, quillayanin, Quil A and gly-cyrrhizic acid (4) have the capacity to induce cell proliferation in lymphocyte cultures at very low concentrations [51]. Induction of B cell proliferation was obtained with crude saponin, T cell proliferation with Quil A, and quillayanin and gly-cyrrhizic acid equally stimulated both T and B lymphocytes. The selective proliferation of subtypes of lymphocytes correlated with restimulation responses by polyclonal mitogens (ConA, PHA), and lipopolysaccharide (LPS). 

A decrease of 0/C and P/C concentration ratios at the surface of Streptococcus sobrims was reported as a result of preincubation with polyclonal antibodies. A combination of the pH-dependent zeta potential and the XPS data suggested that polyclonal antibody adsorption occurred through blocking of surface phosphate. XPS measurements provided evidence for IgG attachment to Pseudomonas aeruginosa. The antibody-modified cells showed a reduced adhesion to glass under flow in a nutrient medium. ... 

A two-site immunometric assay of undecapeptide substance P (SP) has been developed. This assay is based on the use of two different antibodies specifically directed against the N- and C-terminal parts of the peptide (95). Affinity-purified polyclonal antibodies raised against the six amino-terminal residues of the molecule were used as capture antibodies. A monoclonal antibody directed against the carboxy terminal part of substance P (SP), covalently coupled to the enzyme acetylcholinesterase, was used as the tracer antibody. The assay is very sensitive, having a detection limit close to 3 pg/mL. The assay is fiiUy specific for SP because cross-reactivity coefficients between 0.01% were observed with other tachykinins, SP derivatives, and SP fragments. The assay can be used to measure the SP content of rat brain extracts. 

Currently, there are several assays for the measurement of PSA. All of them contain monoclonal or polyclonal antibodies labeled with enzymatic, fluorometric, or radioactive markers. These assays have shown significant variations within the same patient specimens. These variations may result from differences in antibody specificity, reaction kinetics, calibration, or the system s sensitivity. Studies have shown that only free PSA and PSA-ACT show immunological reactivity in these assays. Also, reaction kinetics can influence the molar ratio. Some of these assays with shorter incubation times may specifically bind the free PSA molecule (which is a lower weight form of PSA). In the equimolar assays, changing the incubation... 

Compared to people in a noncontaminated area, plasma IgG levels were also significantly decreased in proportion to increasing plasma levels of TCDD in a cohort exposed in an industrial accident in Seveso, Italy.118 There was no effect on IgM or IgA levels, or on complement levels IgE was not measured. In separate studies, in vitro exposure to TCDD enhanced the spontaneous production of IgE by B cells isolated from atopic but not non-atopic individuals, but did not affect the levels of other isotypes.119 Other recent studies have reported small changes in immune cells from individuals exposed occupationally to PHAH.120121 For example, compared to unexposed controls, a cohort of men exposed occupationally to TCDD had diminished IFNy production in a recall response to tetanus toxin, while IFNy production following polyclonal activation was unaffected.120 This observation is consistent with mouse studies, in which antigen-specific responses are highly suppressed by TCDD, but mitogen-driven T cell responses are less susceptible to impairment.83 88122123... 

Immunochemical methods have been developed and placed on the market to analyze tetracycline residues (see Table 4). Thus, a qualitative EIA has been developed and used to analyze tetracyclines in honey samples with a detection level of 20 pg/kg-1 [96]. A microplate-based indirect ELISA has been developed to analyze tetracyclines using polyclonal antibodies. The assay could measure tetracycline in the range between 0.1 and 6 ng mL L Other tetracycline antibiotics such as chlortetracycline, rolitetracycline, or minocycline are also highly recognized in this assay [98]. Several immunoassay kits are commercially available for the analysis of tetracyclines although, to our knowledge, none of them... 

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