We and others have shown that human basophils can synthesize and release IL-4. However, IL-13, a cytokine that closely resembles IL-4, has not hitherto been described as a basophil product. The production of IL-13 by basophils was demonstrated by immunocytochemistry. Approximately 70% of basophils stimulated with anti-FcεR1α (antibody to the α subunit of IgE receptor type 1) stained for IL-13. Under similar experimental conditions, mononuclear cells failed to stain for IL-13. The cytokine was localized to basophilic granules by electron microscopic examination of immunogold staining. The secretion of IL-13 into the culture supernatant was assayed by ELISA. Kinetic studies showed detectable IL-13 release at 3 h, which steadily increased up to 24 h. This is significantly different from the kinetics of basophil histamine and IL-4 release. IL-13 production was also observed upon stimulation with anti-IgE, anti-FcεRIα, IL-3, and A23187 in a dose- dependent manner. PBMC, neutrophils, and eosinophils isolated from the same donors did not release IL-13 after anti-IgE stimulation. The anti-IgE- induced basophil IL-13 synthesis could be enhanced by IL-3 preincubation (with and without IL-3 preincubation, anti-IgE-induced IL-13 production was 227 ± 99 and 42 ± 13 pg/106 basophils, respectively). PBMC produced a significant amount of IL-13 upon stimulation with PHA, but a low level of IL- 13 in response to A23187 and/or PMA. Eosinophils and neutrophils did not produce IL-13 when cultured with A23187, IL-5, and anti-FcεRIα. This is the first demonstration of IL-13 production by basophils. Our data suggest that basophils, in addition to secreting mediators, can represent an important source of proallergic cytokines.
|Original language||English (US)|
|Number of pages||6|
|Journal||Journal of Immunology|
|State||Published - Jun 15 1996|
ASJC Scopus subject areas
- Immunology and Allergy