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Background: Diagnosis of allergies is mostly based on the patient's clinical history and allergen provocation tests. Determination of specific IgE (sIgE) profiles can be performed to support allergy diagnosis. This is commonly done in vivo by the skin prick test or in vitro with automated systems. Several platforms exist to quantify sIgE levels, but all these methods require access to specific instruments, often delaying the test's results. The IgE luciferase-linked immunosorbent assay (LuLISA) allows bioluminescent quantification of IgE against peanut in microliter samples, but this method awaits extension to other allergens. This study aimed to validate a new method, named LuLIPLEX, for multiplexed bioluminescent detection of sIgE against 20 major molecular allergens., Methods: Quantification of sIgE against 12 recombinant or purified food allergens and eight aeroallergens was performed by LuLIPLEX versus standard IgE detection methods (ImmunoCAP, ISAC, ALEX, or NOVEOS). Multiplexed detection of IgE against these 20 allergens was performed within 45 min using 50 μL of serum, plasma, or whole blood samples., Results: A head-to-head comparison between LuLIPLEX and standard IgE detection methods showed a high correlation among all allergens tested. sIgE profiles in polysensitized subjects could be determined within 45 min in serum and plasma samples, as well as using a single drop of capillary blood., Conclusions: LuLIPLEX is a rapid and sensitive method to quantify sIgE levels against multiple allergens. Given that the test is very fast and can be performed on small and inexpensive luminometers, the IgE LuLIPLEX could allow point-of-care testing of sIgE profiles in allergic subjects., (© 2024 The Author(s). Allergy published by European Academy of Allergy and Clinical Immunology and John Wiley & Sons Ltd.)

Background: Voltage-gated calcium (Ca v 1) channels contribute to T-lymphocyte activation. Ca v 1.2 and Ca v 1.3 channels are expressed in Th2 cells but their respective roles are unknown, which is investigated herein., Methods: We generated mice deleted for Ca v 1.2 in T cells or Ca v 1.3 and analyzed TCR-driven signaling. In this line, we developed original fast calcium imaging to measure early elementary calcium events (ECE). We also tested the impact of Ca v 1.2 or Ca v 1.3 deletion in models of type 2 airway inflammation. Finally, we checked whether the expression of both Ca v 1.2 and Ca v 1.3 in T cells from asthmatic children correlates with Th2-cytokine expression., Results: We demonstrated non-redundant and synergistic functions of Ca v 1.2 and Ca v 1.3 in Th2 cells. Indeed, the deficiency of only one channel in Th2 cells triggers TCR-driven hyporesponsiveness with weakened tyrosine phosphorylation profile, a strong decrease in initial ECE and subsequent reduction in the global calcium response. Moreover, Ca v 1.3 has a particular role in calcium homeostasis. In accordance with the singular roles of Ca v 1.2 and Ca v 1.3 in Th2 cells, deficiency in either one of these channels was sufficient to inhibit cardinal features of type 2 airway inflammation. Furthermore, Ca v 1.2 and Ca v 1.3 must be co-expressed within the same CD4 + T cell to trigger allergic airway inflammation. Accordingly with the concerted roles of Ca v 1.2 and Ca v 1.3, the expression of both channels by activated CD4 + T cells from asthmatic children was associated with increased Th2-cytokine transcription., Conclusions: Thus, Ca v 1.2 and Ca v 1.3 act as a duo, and targeting only one of these channels would be efficient in allergy treatment., (© 2021 European Academy of Allergy and Clinical Immunology and John Wiley & Sons Ltd.)