The in vitro and in vivo effect of corticosteroids on basophil releasability in patients with mild and severe bronchial asthma.
BACKGROUND
While inhalation of corticosteroids (CST) is considered very effective in most asthmatic patients, some require a high dose of oral prednisone to control the disease. Basophils, which participate in inflammation, are responsive to corticosteroids by suppressing histamine release.


OBJECTIVE
We investigated the in vivo (oral prednisone) and in vitro (dexamethasone, DEX) effect on basophil histamine release in mild and steroid-dependent asthmatics.


METHODS
Histamine release from basophils to anti-IgE and anti-IgE + IL3 was evaluated following five days of prednisone given 20 mg twice daily in eight subjects with mild disease and 2 h following their daily prednisone ingestion in eight subjects with severe disease, as well as after in vitro DEX was added to the cells.


RESULTS
Histamine release from basophils was seen following anti-IgE as well as anti-IgE + IL-3. The same amount of release was seen in the mild and severe asthmatics. In vivo prednisone suppressed histamine release to both stimuli and DEX added to the suppression in the mild asthmatics. In the severe ones, DEX showed no inhibitory effect on histamine release.


CONCLUSIONS
Oral and in-vitro CST suppressed histamine release from basophils of mild but not severe CST-dependent asthmatics. Suppression of basophil releasability can be a reflection of asthma severity.
Kivity
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Institute of Pulmonary and Allergic Diseases, Sackler Faculty of Medicine, Tel Aviv University, Israel.
Onn
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A
Agami
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Fireman
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D000284:Administration, Oral; D000305:Adrenal Cortex Hormones / Q000008:administration & dosage / Q000627:therapeutic use*; D000328:Adult; D000704:Analysis of Variance; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use*; D000888:Antibodies, Anti-Idiotypic / Q000494:pharmacology; D001249:Asthma / Q000097:blood / Q000188:drug therapy* / Q000473:pathology; D001491:Basophils / Q000187:drug effects* / Q000378:metabolism*; D003907:Dexamethasone / Q000627:therapeutic use; D004359:Drug Therapy, Combination; D005260:Female; D006636:Histamine Release / Q000187:drug effects; D006801:Humans; D007073:Immunoglobulin E / Q000494:pharmacology; D066298:In Vitro Techniques; D007377:Interleukin-3 / Q000494:pharmacology; D008297:Male; D011241:Prednisone / Q000008:administration & dosage / Q000627:therapeutic use; D012720:Severity of Illness Index
D000305:Adrenal Cortex Hormones; D000893:Anti-Inflammatory Agents; D000888:Antibodies, Anti-Idiotypic; D007377:Interleukin-3; D007073:Immunoglobulin E; D003907:Dexamethasone; D011241:Prednisone