Hapten—protein conjugate

Figure 1 Schematic of the quasi-equihbria using heterologous haptens in coating antigen immunoassay formats. Ka represents the equilibrium constant for binding of antibody (Y) to target analyte (A). Kh is the equilibrium constant for the binding of antibody to hapten-protein conjugate (H-) immobihzed on a solid phase...

Bocher, M., Giersch, T., and Schmid, R.D. (1992) Dextran, a hapten carrier in immunoassays for s-triazines. A comparison with ELISAs based on hapten-protein conjugates./. Immunol. Meth. 151, 1-8. 

Kitagawa, T., Kawasaki, T., and Munechika, H. (1982) Enzyme immunoassay of blasticidin S with high sensitivity a new and convenient method for preparation of immunogenic (hapten-protein) conjugates. J. Biochem. (Tokyo) 92, 585-590. 

Direct activation of T cells (e.g., derived from patients) Cell damage (reactive oxygen species, apoptosis, necrosis) LLNA (topical application, indication of hapten-protein conjugation) Oral exposure studies (using bystander or reporter antigens to read out immunosensitization)... 

Figure 2. Schematic of (top)1, hapten-protein conjugate and ( bottom), antibody...

The utihzation of fluorescence dyes for analytical measurements enhances the sensitivity for the detection of the molecules of interest. First, Cronick and Little made use of evanescent wave excitation for a fluorescence immunoassay, in 1975. By using totally internally reflected light, they excited the fluorescence of a fluorescein-labeled antibody which has become bound to a hapten-protein conjugate adsorbed on a quartz-plate in an antibody solution [41]. Contrary to the label-free high-refractive-index sensors where the mass of the molecule of interest is... 

In this case, the reducing agent was cyanoborohydride. To verify that the conjugate contains intact purine base, a difference spectrum of the hapten-protein conjugate minus protein should be obtained it should be very close to the spectrum of the intact nucleoside or nucleotide alone. Further, the antibodies should be specific for the intact base in comparison with the degradation product. ... 

Antinucleotide sera have been tested also for binding of radiolabeled hapten-protein conjugates or labeled DNA and with quantitative complement fixation assays. Once characterized, specific serum or purified antibodies may be used also in immunohistochemical tests at the level of light or electron microscopy. 

It was not the purpose of this review to present a comprehensive survey of hapten-protein conjugates, but rather to provide sufficient information to guide the researcher in the design of his or her particular experiments. On the other hand, the most practical approaches to the preparation of hapten-protein conjugates were cited. 

The interaction of a non-enzymatic degradation product, D-benzylpenicillenic acid (formed by cleavage of the thiazolidine ring of benzylpenicillin in solution see Fig. 10.3B), with sulphydryl or amino groups in tissue proteins, to form hapten-protein conjugates, is also of importance. In particular, the reaction between D-benzylpenicillenic acid and the e-amino group of lysine (a,e-diamino- -caproic acid, NH2(CH2)4.CH(NH2).COOH) residues... 

The synthesis of the protein conjugates is shown in Figure 3. Commercially available carboxylic acids were converted to activated esters by direct DCC (N,N-dicyclohexylcarbodiimide) coupling with N-hydroxysuccinimide or by conversion to the corresponding acid chloride derivative followed by reaction with N-hydroxysuccinimide. Reactiion of the resulting N-hydroxysuccinimide esters with either BSA or OVA led to the desired lysine bonded nitroaromatic hapten-protein conjugates. 

Figure 1. Structure of ivermectin, showing the major analogs and the sites that were derivatized to form the hapten-protein conjugates used as immunizing and screening antigens. The 4" hemisuccinate ( Site 1 ) or the hemisuccinate formed through the oxygen on carbon 5 ( Site 2 ) were conjugated to carrier proteins as described in Methods.

Table VI. Approaches to Obtain Hapten-Protein Conjugate...

Venables KM, Topping MD, Howe W, et al Interaction of smoking and atopy in producing specific IgE antibody against a hapten protein conjugate. BMJ 1985 290 201-204. (Ill)... 

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