In vitro diagnosis of nickel allergy

Background: Diagnosis of contact allergy is based on clinical data and patch tests. Among in vitro tests, lymphocyte proliferation test (LPT) is most frequently used. A disadvantage of LPT is that it is based on radiochemicals, which restricts its use only to laboratories with radionuclide facilities.

Aim: To find a cytokine secretion assay giving results that correlate best with clinical diagnosis and with LPT.

Methods: PBMC from 14 patients with ACD to nickel and 14 non-allergic controls were tested for their reactivity to nickel. In all subjects, patch tests and LPT with nickel sulphate were done. A range of non-radioactive secretion assays was performed, including ELISpot assays for IL-2, IL-5, IL-13 and IFN-gamma, and ELISA for IL-5 and IFN-gamma. Beside standard culture conditions, cytokine secretion was also measured in cultures favouring the development of Tc1/Th1 or Tc2/Th2 lymphocytes ("skewing" through addition of IL-7 with respectively IL-12 or IL-4).

Results: The best correlation with clinical diagnosis (patch tests and history) was observed for IL-13 ELISpot with Tc2/Th2 skewing (r=0.654, P<0.001), followed by LPT (r=0.612, P<0.001), and IL-5 ELISpot with Tc2/Th2 skewing (r=0.551, P=0.002). The non-radioactive method that correlated best with LPT was IL-2 ELISpot (r=0.809, P<0.001), followed by IL-13 ELISpot (r=0.778, P<0.001), and IL-5 ELISA (r=0.669, P<0.001). Interestingly, IFN-gamma ELISpot and IFN-gamma ELISA correlated very poorly with both clinical diagnosis and LPT results (r<0.010 in each case).

Conclusions: IL-13 ELISpot with Tc2/Th2 skewing correlates best with clinical diagnosis of contact allergy to nickel, whereas IL-2 ELISpot seems a good non-radioactive alternative for lymphocyte proliferation test.

Related articles:

1. Spiewak R, Moed H, von Blomberg BME, Bruynzeel DP, Scheper RJ, Gibbs S, Rustemeyer T. Allergic contact dermatitis to nickel: Modified in vitro test protocols for better detection of allergen-specific response. Contact Dermatitis 2007, 56 (2): 63-69.
2. Spiewak R. Atopy and contact hypersensitivity: a reassessment of the relationship using objective measures. Ann Allergy Asthma Immunol 2005; 95 (1): 61-65.
3. Spiewak R. Allergische Kontaktdermatitis im Kindesalter. Eine Übersicht und Meta-Analyse [Allergic contact dermatitis in childhood - a review and meta-analysis]. Allergologie 2002; 25 (7): 374-381.

Links:

Institute of Dermatology, Krakow, Poland

English-speaking dermatologist in Krakow (Cracow), Poland

Deutschsprechender Hautarzt in Krakow (Krakau), Polen

Sensimun (formerly Celimun Biomedical Research) - outsourcing in allergy and immunology

ELISpot - training, implementation, outsourcing