Flow‐assisted allergy diagnosis: current applications and future perspectives

Abstract

Physicians predominantly rely upon quantification of serum‐specific immunoglobulin E (IgE) and/or skin test to confirm clinically suspected IgE‐mediated allergy. However, for various reasons, identification of the offending allergen(s) and potentially cross‐reactive structures is not always straightforward. Flow‐assisted allergy diagnosis relies upon quantification of alterations in the expression of particular basophilic activation markers. Actually, upon challenge with a specific allergen, basophils not only secrete quantifiable bioactive mediators but also upregulate the expression of different markers which can be detected efficiently by flow cytometry using specific monoclonal antibodies. Currently, the technique has been applied in the investigation of IgE‐mediated allergy caused by classical inhalant allergens, food, Hevea latex, hymenoptera venoms and drugs. It is also appreciated; the technique proves valuable in the diagnosis of non‐IgE‐mediated (anaphylactoid) reactions such drug hypersensitivity and the detection of autoantibodies in certain forms of chronic urticaria. This review will not address immunologic features, characteristics and general pitfalls of flow‐assisted analysis of in vitro‐activated basophils as summarized elsewhere. After a recapitulation of the principles and some specific technical issues of flow‐assisted analysis of in vitro‐activated basophils, we principally focus on the current clinical and research applications of the basophil activation tests. Personal experience of both research groups is provided, where appropriate. Finally, a viewpoint on how the field might evolve in the following years is provided.

Evidence for a functional role of IgE anticitrullinated protein antibodies in rheumatoid arthritis

“…As described previously (35), heparinized whole blood was stimulated at 37°C for 20 min with 10 μg/mL native noncitrullinated fibrinogen (Sigma Aldrich), 10 μg/mL citrullinated fibrinogen, 0.5 U/mL PAD (Sigma Aldrich), 10 μg/mL noncitrullinated MBP, 10 μg/mL citrullinated MBP, 10 μg/mL monomeric IgG (Jackson ImmunoResearch Laboratories, Inc.), 10 or 100 μg/mL heat-aggregated IgG, HBSS as a negative control, and 1 μg/mL anti-IgE (Pharmingen) as a positive control. Human fibrinogen or MBP was citrullinated as described previously (34).…”

Basophil activation test versus radio-immunoassay in the diagnosis of β-lactam immediate-type hypersensitivity reactions

“…A larger number of cases would be needed to assess the difference between the two in vitro techniques used in the evaluation of β-lactam hypersensitivity. For drugs the lower observed sensitivity of the test probably reflects a weaker allergenicity of these molecules (22). The low sensitivity can also be explained by the time-dependent decrease in reactivity of the cells involved in allergic reactions.…”

Allergic hypersensitivity to topical and systemic corticosteroids: a review

“…The in vivo tests are mainly Ôskin prickÕ test and/or an early-reading intradermal reaction (IDR) test in cases of IAHS and Ôpatch testÕ and/or a latereading IDR test in cases of DAHS. In vitro diagnosis may include the identification of basophil activation/ degranulation and IgEs specific to the drug for IAHS (10,11) and lymphocyte transformation test (LTT) and IFN-gamma enzyme-linked immunospot assay (ELISPOT) for DAHS (12)(13)(14). Biological diagnosis of a DAHS reaction has made significant progress in recent years thanks to the work of Rozie`res et al (12) and Pichler et al (14).…”

“…The basophil activation test, based on flow cytometry, consists of analysing and quantifying changes in the expression of blood basophil activation markers in the presence of a given allergen (10,11,98). The most common activation markers are CD63 and CD203c.…”