Haptenic inhibition

The specificity of the antiserum raised against the Lea neoglycoprotein (9) was determined by hapten-inhibition studies using synthetic oligosaccharides,72 and derivatives of bovine and horse serum-albumin to which the Lea trisaccharide had been attached.73 On the basis of hapten inhibition of precipitation, this antiserum was shown to be highly specific for the carbohydrate portion of the synthetic antigen,... 

Fig. 1.—Hapten Inhibition of the Precipitation of the Synthetic Antigen 8-Carboxy-octyl 4-Chloro-4-deoxy-0-D-galactopyranoside-BSA by Rabbit Antiserum Raised Against 8-Carboxyoctyl 0-D-Galactopyranoside-BSA (12 in Table I). [The haptens were the oj-earboxyalkyl /3-D-galactopyranosides having the aglycons (1) 8-carboxyoctyl, (2) 4-carboxybutyl, (3) 2-carboxyethyl, and (4) carboxymethyl (taken from Ref. 73).]...

The specificity of the antibodies was also verified by hapten-inhibition tests, the results of which are shown in Fig. 8. In these tests decreasing amounts of antigen were used with the pure antibodies and with antibodies that had been treated with potential inhibitors for 2 h. Agar diffusion was used to observe the rate of formation of precipitin bands with the various amounts of antigen. A comparison of the amount of antigen required to... 

Fig. 8.—Hapten inhibition of anti-glucose antibodies. A, B, C = a antibodies and D, E, F = j8 antibodies by methyl a-D-glucopyranoside or methyl /S-D-glucopyranoside. Wells 1-6 contain decreasing concentration of a-g)ucosyl-BSA and wells 7-12 contain decreasing concentration of /3-glucosyl-BSA. Wells not numbered contain the same concentration of antigen as in the plates horizontally adjacent.

Diffusion in agar performed by the conventional method shows a strong reaction between the antibody and Man-BSA, but not with BSA (Fig. 12, plates A). However, both compounds give precipitin complex with anti-BSA serum. Oxidation of the antigens with periodate no longer gives a precipitin reaction with the anti-mannose antibodies, but has no effect on the anti-BSA antibodies. Hapten-inhibition results are also shown in Fig. 12, plates C and D. These tests are conducted with the purified antibody... 

Fig. 12.—Reactivity of anti-a-mannose antibodies and anti-BSA antibodies with the native and periodate-oxidized mannose-glycoconjugate and BSA (plates A and B). M = Man-BSA, xM = periodate-oxidized Man-BSA, B = BSA, xB = periodate-oxidized BSA, A = antimannose antibodies, A2 = anti-BSA antibodies. Plates C and D show hapten inhibition of purified anti-mannose antibodies (A ) with mannose (L). The amount of antigen in the outer wells ranges from 20 /u.g in well 1 to 1 /u.g in well 6. [Reprinted with permission from J. H. Pazur, B. Liu, and T. Witham. J. Protein Chem., 13 (1994) 59-66.]...

Fig. 13.—A Agar diffusion of immune sera (Se), 1-thio-D-mannose antibodies (A ), and anti-BSA antibodies (A2) against Man-S-BSA (/) and BSA (2). B Agar-diffusion plate of anti-Man-S-antibodies and antibodies oxidized by peroxypropanoic acid for 0, 4, and 8 h. C, D, E, and F Hapten inhibition by agar diffusion, A = purified anti-Man-S antibodies I = antibodies + p-nitrophenyl 1 -thio-a-D-mannopyranoside 12 = antibodies + D-mannose I3 = antibodies + ethyl 1-thio-a-o-mannoside 1 to 6, outer wells contain decreasing concentration of Man-S-BSA. (Reprinted with permission from Journal of Protein Chemistry, Volume 9, J. H. Pazur, B. Liu, Nan Q Li, and Y. C. Lee, pp. 143-150, copyright 1990 Journal of Protein Chemistry.)...

Fig. 24.—A Hapten inhibition of the anti-lactose antibodies by lactose and galactose and derivatives. B Dissociation of anti-lactose antibodies into light and heavy chains followed by density-gradient centrifugation. (A. Reprinted with permission from Journal of Biological Chemistry, Volume 253, J. H. Pazur, K. L. Dreher, and L. S. Forsberg, pp. 1832-1837, copyright 1978 Journal of Biological Chemistry B, Reprinted with permission from Journal of Protein Chemistry, Volume 6. J. H. Pazur, M. E. Tay, B. A. Pazur, and F. J. Miskiel, pp. 387-399, copyright 1987 Journal of Protein Chemistry.)...

Quantitative hapten inhibition tests were also performed.73 The amount of myeloma protein-dextran complex that formed in individual tests was measured by the determination of protein in the precipitate, using a colorimetric method.74 The precipitin tests were performed in a final volume of 0.2 mL, which comprised 80 pL of 0.02 M phosphate buffer of pH 7, 20 pL of ascitic fluid or purified myeloma protein, and 100 pL of dextran B-1355S solution in phosphate buffer of pH 7. The extent to which glucose... 

Fig. 41.—Hapten inhibition of group L polysaccharide and antibodies by a- and /3-d-GlcNAc-l-P. (Reprinted from Journal of Immunological Methods, Volume 75, J. H. Pazur and S. A. Kelly, pp. 107-116, copyright 1984 with kind permission of Elsevier Science—NL, Sara Burgerhartstraat 25, 1055 KV Amsterdam, The Netherlands.)...

Although the interaction of lectins with polysaccharides, glycoproteins, and glycolipids is, without dispute, more complex than with simple sugars, the results of hapten-inhibition studies employing... 

Studies on the carbohydrate-binding specificity of the fava-bean lectin, as determined by hapten inhibition of hemagglutination,140,213,466-469 showed that the lectin is inhibited by Makela s group III sugars (see Table VI). Hemagglutination by the lectin was inhibited by... 

Ljungstrom KG. Safety of dextran in relation to other colloids—ten years experience with hapten inhibition. Infusionsther Transfusionsmed 1993 20(5) 206-10. 

Ljungstrom KG, Wilknan B, Hedin H. Hapten inhibition of dextran anaphylaxis. Nine years of post-marketing surveillance of dextran 1. Ann Fr Anesth Reanim 1993 12(2) 219-22. 

Negligible cross-reactivity has been reported in both animal and human studies involving hapten inhibition, skin tests, and treatment of penicillin-allergic patients with therapeutic doses of aztreonam (12,14-19). Aztreonam therefore seems to be a safe alternative for patients with penicillin allergy. However, the numbers of safely treated patients reported are still small, and immediate type hypersensitivity to aztreonam has been reported in patients with penicillin allergy (20-23). 

In order to examine the substructural determinants of sialic acid required for MAG binding, a second study by Kelm and coworkers [33] evaluated the inhibitory potential of simple sialic acid glycosides towards MAG and sialoadhesin using their hapten inhibition assay (Table 16.4). 

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