Gennaro Maietta
Pignatelli Institute, Italy
Title: Basophil activation test as biomarker of allergic desensitization
Biography
Biography: Gennaro Maietta
Abstract
Statement of the Problem: Specific immunotherapy (SIT) is able to modify the natural history of allergic diseases. In particular, SIT induces an immunological tolerance against the allergen and clinical control of disease. Clinical efficacy of subcutaneously SIT (SCIT) has been clearly demonstrated as well as sublingual SIT (SLIT), but we need to identify biological markers for SIT in the attempt to reveal patients with high risk of adverse reactions, to monitor the therapy outcome and to predict relapses after SIT discontinuation. We know that both SCIT and SLIT induce a sudden increase of the basophil sensitivity in the first weeks of immunotherapy followed by a gradual decrease over some months. The purpose of this study is to evaluate if Basophil Activation Test (BAT) can monitor the progressive desensitization of the patient during SIT.
Methodology: Patients between 18 and 60 years old allergic to wall pellitory or grass were enrolled in the study. Some of them were treated with SCIT, while others preferred to be treated with SLIT. BAT was performed at the beginning of the treatment and during pollen season for two years. BAT was performed with specific allergen at different concentrations in attempt to evaluate basophil activation as CD-sens (allergen concentration able to induce 50% of maximum activation). SIT outcome was evaluated clinically by using a VAS score.
Findings: BAT showed a higher and earlier reduction of CD-sens in patients treated with SCIT compared with SLIT treated ones. In some patients, it was not possible to observe a reduction in CD-sens. These patients had experienced persistence or worsening of clinical symptoms.
Conclusion & Significance: BAT should represent a useful tool in evaluating progressive desensitization during SIT by monitoring basophil sensitivity. CD-sens could be an interesting biomarker in deciding how long the SIT continues and when to suspend it. Probably, it could represent a biomarker in predicting clinical relapses after immunotherapy discontinuation.