Interleukin-1 production by monocytes from patients with allergic asthma after stimulation in vitro with lipopolysaccharide and Dermatophagoides pteronyssinus mite allergen.

Monocytes from 6 patients with asthma and positive bronchial challenge with extract from the house dust mite Dermatophagoides pteronyssinus (Dp) were stimulated with lipopolysaccharide (LPS) and allergen extract from Dp. In order to neutralize putative endotoxin contamination of the allergen extract, some cultures were incubated in the presence of polymyxin B. Interleukin-1 (IL-1) activity was assayed by the comitogenic activity of the crude monocyte supernatants on phytohemagglutinin-stimulated murine thymocytes. Our results suggest that, upon stimulation with LPS and allergen, monocytes from atopic patients possess a normal capacity to produce IL-1. Like monocytes from healthy controls, patient monocytes do not produce IL-1 spontaneously. The specificity of the allergen stimulus is not well-defined, and further characterization of the IL-1-inducing property awaits the availability of endotoxin-free allergen preparations.