Basophils from five of six human donors released histamine in response to neutrophil attractant/activation protein-1 (NAP-1). Histamine release by this protein was concentration-dependent over the range of 3×10-7 M to 4×10-6 M. At 4×10-6 M, the mean agonist-induced release was 16 ± 3% (SEM) of total basophil histamine. For the same basophil preparations, release by anti-IgE was 35 ± 6%. The chemotactic protein did not cause release of histamine from basophils at 0°C or in the presence of 10 mM EDTA. The time-course of histamine release was rapid; release was 43% of maximal after 30 s and maximal after 1 min of incubation. Thus, in addition to its previously characterized neutrophil chemotactic and activating properties, this protein activates human basophils.
- Histamine release
- Neutrophil attractant/activation protein-1
ASJC Scopus subject areas
- Immunology and Allergy