Endotyping Cellular and Humoral Immunoreactivity against Allium Spices and Sulfites Preservatives in Allergic Patients: A Retrospective Study

Background: Spices from the Allium genus season food worldwide, and their widespread use may produce allergic reactions by contact or ingestion. However, the Non–IgE-mediated immunoreactivity against these allergens has not yet been adequately investigated.

Aim: To evaluate the potential of the Tube Titration of Precipitins (TTP) and the Leukocyte Adherence Inhibition Test (LAIT) to discriminate cellular and humoral immunoreactivity against two Allium spices (garlic and onion) and a sulfite derivative in patients with Non–IgE-mediated allergic phenotypes.

Methodology: Two cohorts of allergic patients suspected of Non–IgE-mediated hypersensitivity against Allium spices and sulfite derivatives were investigated with the help of TTP or LAIT, simultaneously against extracts of garlic, onion, and sodium bisulfite. The results of the semi-quantitative serum TTP against 1 mg/mL garlic extract, 1 mg/mL onion extract, and 1 mg/mL sodium bisulfite were distributed in ranges through cascade distribution charts. The results of the Leukocyte Adherence Inhibition (LAI) percentage promoted by the ex vivo challenges against 1 mg/mL garlic extract, 1 mg/mL onion extract, and 1 mg/mL sodium bisulfite were distributed in ranges through cascade distribution charts. The statistical differences inside these cohorts were calculated.

Results: Paired t-test indicated a non-significant difference between garlic TTP and onion TTP (p-value = 0.761); a non-significant difference between sulfites TTP and garlic TTP (p-value = 0.112);

a non-significant difference between sulfites TTP and onion TTP (p-value = 0.058); a non-significant difference between garlic TIAL and onion TIAL (p-value = 0.942); a significant difference between sulfites TIAL and garlic TIAL (p-value < 0.001) and a significant difference between sulfites TIAL and onion TIAL (p-value < 0.001).

Conclusion: Results support that the TTP and LAIT performed with sodium bisulfite, garlic, and onion extracts may discriminate diverse degrees of humoral and cellular immunoreactivity in patients suffering from diversified allergic phenotypes.