Increasing time interval and decreasing allergen dose interval improves ex vivo desensitization of human blood basophils

Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaperJournal articleResearchpeer-review


BACKGROUND: Desensitization is a method for inducing temporary tolerance to allergen. The mechanism underlying desensitization is yet to be established.

METHODS: Basophil granulocytes in whole blood from grass pollen allergic subjects were desensitized ex vivo by sequential addition of increasing allergen concentrations. At each step basophil activation (CD193(+) CD63(+) ) was monitored with and without (background activation) allergen challenge at optimal concentration. The sequential desensitization protocol was compared to a single-dose desensitization protocols with threshold and subthreshold allergen concentrations. Incubation intervals and allergen concentrations were varied in order to optimise the protocol.

RESULTS: Sequential desensitization effectively reduced basophil response. The single-dose subthreshold protocol and single-dose threshold protocols did not reduce basophil activation with optimal allergen challenge from a mean 57.1 (95% CI 32.7-81.5) to 50.4% (95% CI 16.3-84.4; n=5; p=0.43) and 45.0% (95% CI 23.1-66.9; p=0.14) respectively, while the sequential desensitization protocol reduced activation to a mean 37.2% (95% CI 16.3-58.1; p=0.018). Reducing incubation time from 10 to 5 minutes increased mean background activation from 22.4 (95% CI 11.7-33.1) to 30.0% (95% CI 19.7-40.3; n=5; p=0.026). Increasing time intervals from 10 to 20 minutes reduced background activation from 30.9 (95% CI 22.8-39.0) to 21.9% (95% CI 16.0-27.7; n=5; p=0.020). Increasing allergen concentrations intervals from 2-fold to 5- and 10-fold did not have significant effect on basophil activation.

CONCLUSIONS: Sequential desensitization ex vivo effectively attenuates the basophil response to allergen. Increasing the time spent at each step improves desensitization. This protocol could be valuable for investigation of the mechanism of desensitization. This article is protected by copyright. All rights reserved.

Original languageEnglish
JournalCytometry. Part B: Clinical Cytometry
Pages (from-to)340-347
Number of pages8
Publication statusPublished - Sep 2017

See relations at Aarhus University Citationformats

ID: 100551901