Parameters in Elicitation and Inhibition of Allergic Reactions

Molecular Parameters in Elicitation and Inhibition of Allergic Reactions 

Antigens Immunogenicity Precipitation of anti-BPO antibody Elicitation of hypersensitivity  

Since elicitation of antibody-mediated hypersensitivity reactions requires as a rule at least divalent or trivalent antigens, and is usually best achieved with multivalent conjugates, the specific inhibition of such reactions by monovalent haptens seems theoretically possible and depends primarily on the concentrations of inhibiting and eliciting haptens and on antibody affinity and concentration. It has been shown that anaphylactic reactions in vivo assessed by the PCA technique, or by observation of systemic shock or urticarial skin reactions, can be completely in- 

Inhibition of cellular hypersensitivity, such as contact sensitivity, is not readily achieved with simple haptens. DNP-lysine, for instance, did not markedly depress contact reactions to l-chloro-2,4-dinitrobenzene in guinea pigs whereas 2,4-dini-trobenzene sulfonate, which is able to conjugate in vivo, temporarily abolished contact reactions after parenteral injection (de Weck et al. 1964). 

With regard to the inhibition of primary antibody responses, it may prove difficult to maintain sufficiently high concentrations of low molecular weight hapten in vivo. Thus, N -BPO-N -formyl-L-lysine did not inhibit the primary anti-BPO response to a BPO-BGG conjugate injected intravenously into rabbits, whereas with in vitro induction systems, specific inhibition of anti-hapten antibody responses can be observed in a number of instances. Secondary anti-hapten responses are easier to inhibit and N -BPO-iV -formyI-L-lysine strikingly abolished anti-BPO antibody synthesis in primed rabbits secondarily injected with BPO-BGG (for review see de Weck 1974), 

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