Authors

Discussion

Echinococcus granulosus is the causative agent of cystic echinococcosis in humans infected as accidental hosts. Diagnosis is usually achieved using computerized imaging technologies, complemented by serological analyses. However, the latter have serious limitations in terms of specificity and, to a lesser extent, sensitivity. Even though Echinococcus infection induces a strong IgE response in infected hosts including human, this isotype is currently underexploited by current serological diagnostic techniques, which are mostly based on detection of parasite-specific IgG.

Here, we show proof-of-principle that humanized IgE reporter systems can be used advantageously for diagnosis of cystic echinococcosis. We introduce our new RBL NPY-mRFP reporter system, which requires neither expensive substrates nor overnight incubation for detection of activation. In this reporter system, NPY-mRFP is pre-formed in granules, and activation can be conveniently assessed using fluorescence measurements as soon as 45-60 minutes after activation.

Our data obtained using raw cyst fluid as antigen demonstrate the high discriminating power of IgE-based reporter systems for cystic echinococcosis diagnosis. We are currently employing several immunological and bioinformatic techniques, together with recombinant expression and protein purification, to identify known and novel Echinococcus granulosus allergens in cyst fluid and assess their suitability as diagnostic antigens using our reporter systems.

Key words: Echinococcus granulosus, diagnosis, cystic echinococcosis, RBL, IgE, Reporter system, NPY-mRFP, Allergen, Degranulation.