[The Pharmacia CAP system as a new measure of specific IgE. Application in the diagnosis of hypersensitivity to the venom of the Vespula wasp]

Abstract

Every improvement can make the measurement of specific IgE more effective. This is the case with the CAP system, a new solid phase technique which uses an Immunocap made from hydrophilic polymer, encased in a capsule, for the fixation of anti-IgE or allergen. The Immunocap fixes 3 times more protein than paper discs. Another improvement is that of calibration of the CAP System by the WHO standard for IgE, with the results expressed in KUI/I: 0.35 to 100 KUI/I for specific IgE and 2 to 2,000 KUI/I for total IgE. The study was of patients who had an anaphylactic or systemic reaction after wasp stings. The subjects were divided into two groups A and B and compared with a reference Groupe C. The study also included subjects who were sensitive to mites, grass pollens and egg. Finally, the technique itself was submitted to a reproducibility test. The results confirm that the sensitivity and specificity of the test were both equal to unity. The CAP System therefore offers the possibility of detecting the lowest amounts of IgE.