Comparative Analysis of Extract-based Skin Test and IgE detection, Singleplexed Molecule-based IgE Detection and a Molecule-based Microarray System

RATIONALE: Specific IgE (sIgE) are produced by the immune system toward allergenic components. Proteomic microarray is a new in vitro method which might detect sIgE to purified native or recombinant allergens. We sought to compare IgE detection results using the microarray system (multiplex testing) with the extract-based skin test (ST) and with sIgE detection by a singleplex method based on either extracts or molecules.METHODS: 277 consecutive patients affected by respiratory allergy were enrolled in the study. All subjects underwent ST to grass (Phl p), birch (Bet v), cypress (Cup a), cat (Fel d), dog (Can f), house dust mites (Der f, Der p), pellitory (Par j), Alternaria (Alt a) (Allergopharma, Germany) and sIgE detection (CAP, Phadia, Sweden) using commercial allergenic extract preparations and recombinant allergens from Bet v, Par j, Phl p. Sera of all patients were analysed to define their allergen profile by the ISAC microarray (IgEa)(VBC-Genomics, Austria). The comparative analysis has been carried out by pair matching the results from two different methods.RESULTS: Studied subjects and results expressed as percentage of positive findings versus the second test are reported as “Allergen; No.; ST/sIgE; ST/IgEa; sIgE/IgEa: Alt a; 68; 94.03; 89.71; 92.06 - Bet v; 109; 93.33; 77.98; 93.88 - Can f; 50; 72.73; 44; 65.63 - Cup a; 169; 92.68; 86.39; 99.34 - Der f; 172; 92.56; 65.7; 70.54 - Der p; 174; 91.86; 68.39; 77.22 - Fel d; 129; 92.74; 80.62; 86.96 - Par j; 109; 98.11; 88.07;118.27 - Phl p; 204; 96.48; 88.73; 95.83.Almost overlapping results were obtained when comparing in vitro IgE reactivity to selected allergenic molecules.CONCLUSIONS: Evaluation of the ISAC system by means of comparative testing with established in vivo and in vitro tests leads to an overall positive validation result. RATIONALE: Specific IgE (sIgE) are produced by the immune system toward allergenic components. Proteomic microarray is a new in vitro method which might detect sIgE to purified native or recombinant allergens. We sought to compare IgE detection results using the microarray system (multiplex testing) with the extract-based skin test (ST) and with sIgE detection by a singleplex method based on either extracts or molecules. METHODS: 277 consecutive patients affected by respiratory allergy were enrolled in the study. All subjects underwent ST to grass (Phl p), birch (Bet v), cypress (Cup a), cat (Fel d), dog (Can f), house dust mites (Der f, Der p), pellitory (Par j), Alternaria (Alt a) (Allergopharma, Germany) and sIgE detection (CAP, Phadia, Sweden) using commercial allergenic extract preparations and recombinant allergens from Bet v, Par j, Phl p. Sera of all patients were analysed to define their allergen profile by the ISAC microarray (IgEa)(VBC-Genomics, Austria). The comparative analysis has been carried out by pair matching the results from two different methods. RESULTS: Studied subjects and results expressed as percentage of positive findings versus the second test are reported as “Allergen; No.; ST/sIgE; ST/IgEa; sIgE/IgEa: Alt a; 68; 94.03; 89.71; 92.06 - Bet v; 109; 93.33; 77.98; 93.88 - Can f; 50; 72.73; 44; 65.63 - Cup a; 169; 92.68; 86.39; 99.34 - Der f; 172; 92.56; 65.7; 70.54 - Der p; 174; 91.86; 68.39; 77.22 - Fel d; 129; 92.74; 80.62; 86.96 - Par j; 109; 98.11; 88.07;118.27 - Phl p; 204; 96.48; 88.73; 95.83. Almost overlapping results were obtained when comparing in vitro IgE reactivity to selected allergenic molecules. CONCLUSIONS: Evaluation of the ISAC system by means of comparative testing with established in vivo and in vitro tests leads to an overall positive validation result.