Induction of Histamine Release and Desensitization in Human Leukocytes

Abstract

Histamine release from normal human leukocytes can be induced by anti‐IgE or protein A from Staphylococcus aureus. After incubation in buffer at 37°C for various time intervals or repeated washings with buffer, or both procedures, the leukocytes lose most of their reactivity to protein A, whereas the reactivity to anti‐IgE is unaltered. Cells deprived of their protein A reactivity can be induced to release histamine by IgG complexed with protein A. Maximal release (23%–81%) from 0.6–1.0 × 107 leukocytes per ml is obtained if the mixture contains 1–2 μg protein A and 8–16 μg IgG per ml. The ratio between protein A and IgG in the most active mixtures is 1:8 or 1:16 on a weight basis, which corresponds to 2–4 IgG molecules per protein A molecule. Heat treatment does not destroy the capacity of IgG to mediate histamine release. Mixtures of protein A and the Fc part of IgG can also initiate the release. Furthermore, it is shown that the protein A‐IgG mixture and anti‐IgE induce cross‐desensitization to each other. This indicates that, like cell‐bound IgG, IgG in complex with protein A triggers partially the same reaction sequence as IgE.

Influence of Detergent on Aerosol Allergic Sensitization with Enzymes of <i>Bacillus subtilis</i>

“…It has also been shown that sensitization to the enzyme can be induced experimentally in both rhesus monkeys [24] and guinea pigs [31], and a limited number of reports indicate that tryp sin and chymotrypsin can induce anaphylactoid responses [16,17,19].…”

Anaphylatoxin-induced histamine release with human leukocytes: studies of C3a leukocyte binding and histamine release.

“…Recently, several studies have emphasized that C5a seemed to be the major anaphylatoxin-producing basophil histamine release after complement activation with immune complexes or zymosan (3)(4)(5)(6)(7). In this paper, we have demonstrated histamine release from human basophil granulocytes by purified human C3a and the synthetic COOH-terminal peptides based on the structure of C3a, a pentapeptide, Leu-Gly-Leu-AlaArg (5R),1 and an octapeptide, Ala-Ala-Ala-Leu-GlyLeu-Ala-Arg (8R).…”

Enhancement by a Serum Factor of Immunoglobulin-Mediated Histamine Release from Human Leukocytes

“…Anti-IgE sera were produced in rabbits as pre viously described [15]. IgG from these anti-IgE sera was isolated by chromatography on a DEAEcellulose column followed by further purification on protein A linked to Sepharose 6-B (Pharmacia Fine Chemicals, Uppsala).…”

“…It is currently agreed that the mechanisms for antigen and anti-IgE-triggered release are identical [9]. The Staphylococcus aureus cell wall constituent, protein A, is another substance used during recent years to study mechanisms involved in allergic histamine release from human leukocytes [14][15][16]. The usefulness of protein A depends on its capacity to combine with the Fc part of hu man IgG but not with IgE [3,17].…”