Immunoreactivity against Dermatophagoides pteronyssinus Assessed by the Leukocyte Adherence Inhibition Test in Patients with Intrinsic Atopic Dermatitis and Correlated “Intrinsic” Non–IgE-mediated Allergic Conditions

Background: Due to the lack of standardized laboratory procedures able to demonstrate specific immune responses against the culprit allergens, the non—IgE-mediated allergy syndromes are a group of conditions diagnosed mostly by clinical examination and exclusion criteria. Objective: To evaluate the opportunity of the Leukocyte Adherence Inhibition Test (LAIT) to discriminate specific immunoreactivity against Dermatophagoides pteronyssinus (Dp) in a group of patients with non–IgE-mediated chronic allergic conditions. Methods: Ex vivo challenge tests performed with Dp were monitored by LAIT in patients presenting diverse non–IgE-mediated allergic conditions: intrinsic Atopic Dermatitis (iAD), intrinsic Allergic Rhinitis (iAR), intrinsic Ocular Allergy (iOA), intrinsic Chronic Pharyngitis (iCP), and intrinsic Asthma (iAS). Results: The mean LAI of the control group was 7%; the mean LAI of the iAR group was 34%; the mean LAI of the iCP group was 44%; the mean LAI of the iAS group was 45%; the mean LAI of the iOA group was 47%; the mean LAI of the iAD group was 55%. The non-parametric Wilcoxon-Mann-Whitney U test comparing the control group with each other group showed significance with p-value < α = 0.05 for all groups. Conclusion: The Leukocyte Adherence Inhibition Test is an easy, quick, and inexpensive ex vivo immunoassay with the potential to predict individual immunoreactivity against HDM allergens in real-world patients with non–IgE-mediated allergies.

Assessment of Immunoreactivity against Therapeutic Options Employing the Leukocyte Adherence Inhibition Test as a Tool for Precision Medicine

Background: The Precision Medicine’s approach employs the endotype concept as a central feature to personalize medical treatment. Individual immunoreactivity, alongside characteristics such as genetics, environment, and diet, is one of the factors that differentiates the therapeutic-driven endotypes. Objective: To evaluate the opportunity of the Leukocyte Adherence Inhibition test to differentiate the immunoreactivity between two similar therapeutic agents employed on Allergen Immunotherapy. Methods: Side by side Leukocyte Adherence Inhibitions tests were performed with ovalbumin and carbamylated ovalbumin on a population of 33 self-reported egg-allergic individuals. Results: The results showed two endotypes inside the immune response of the studied groups: The first endotype was defined by the 16 individuals that presented a significant decrease in ovalbumin’s immunoreactivity after carbamylation (mean of differences = 35%; p = 0.002). The second endotype was defined by 17 individuals that presented a significant increase in ovalbumin’s immunoreactivity after carbamylation (mean of differences = 32%; p = 0.001). Conclusion: The Leukocyte Adherence Inhibition test was able to differentiate two distinct immunoreactivity patterns when comparing two similar therapeutic agents suggesting, as proof of concept, a potential role to be employed as a Precision Medicine tool.

A Novel Utility for an Old Method: The Leukocyte Adherence Inhibition Test Is an Easy Way to Detect the Immunoreactive Interference of the Collection Tube Anticoagulant on Cellular Immunoassays

The leukocyte adherence inhibition (LAI) test was designed to evaluate the presence of cellular immunoreactivity against specific antigens and is highly sensitive to analytical interference. To compare the performance of the LAI test among plasmas obtained with different anticoagulants, 36 blood samples of allergic subjects were divided into three tubes with heparin, sodium citrate, and EDTA. The adherence was assessed with the hemocytometer technique. The mean adherence of each group was compared as well as the number of tests with inappropriate adherence (<25%). Of the 36 tests, there were 4, 9, and 21 with inappropriate adherence in the groups of heparin, citrate, and EDTA, respectively. Of these last, 5 samples also did not demonstrate proper adherence with sodium citrate and 1 sample did not show proper adherence with any anticoagulant. The anticoagulant in the collection tube can elicit a specific immune response, becoming an interferent for the LAI test. In this case, there is the possibility of redoing the test using another anticoagulant. Performed with different anticoagulants, the LAI test may be used as a preanalytical tool for choosing the less immunoreactive anticoagulant for more complex immunoassays.