BACKGROUND: Schistosomiasis mansoni is a debilitating and sometimes fatal disease. Accurate diagnosis plays a key role in patient management and infection control. However, currently available parasitological methods are laborious and lack sensitivity. The selection of target antigen candidates has turned out to be a promising tool for the development of more sensitive diagnostic methods. In our previous investigations, the use of crude antigens led to false-positive results. Recently, focus has been given to highly purified Schistosoma mansoni antigens, especially to circulating antigens.<br /><br />METHOD: Thus, our main goal was to test different types of circulating cathodic antigen glycoprotein (CCA), as "crude antigen," the protein chain of recombinant CCA and two individual peptides. These schistosome proteins/peptides were tested in a new diagnostic method employing immunomagnetic separation based on the improvement of antigen-antibody binding.<br /><br />PRINCIPAL FINDINGS: Use of recombinant CCA as a diagnostic antigen allowed us to develop a diagnostic assay with high sensitivity and specificity with no false-negative results. Interestingly, the "crude antigen" worked as a good marker for control of cure after praziquantel treatment.<br /><br />CONCLUSIONS/SIGNIFICANCE: Our new diagnostic method was superior to enzyme-linked immunosorbent assay in diagnosing low endemicity patients.
Grenfell, R., Harn, D. A., Tundup, S., Da’dara, A., Siqueira, L., & Coelho, P. M. Z. (2013). New Approaches with Different Types of Circulating Cathodic Antigen for the Diagnosis of Patients with Low Schistosoma mansoni Load. PLoS Neglected Tropical Diseases, 7(2). https://doi.org/10.1371/journal.pntd.0002054