For this study, six nanobodies with affinity for SEA were generated starting from mRNA of SEA immunized alpaca. The six nanobodies bearing a C-terminal histidine tag were shown to bind SEA coated on maxisorp 96 well ELISA plate (NuncTM) ELISA. In this binding assay, Nb1 and Nb19 showed better binding to SEA than Nb2, 7, 8 and 17. The successfully produced, biotinylated versions of Nb1, 7 and 8 did not show significant binding to SEA coated on ELISA plate. With this, the capability of a Nb to be used as part of a diagnostic test for schistosomiasis based on SEA was demonstrated. However, since this test was performed on egg lysate coated on ELISA plate, the result obtained is only the beginning. Indeed, the desired test format for a diagnositc test is a sandwich system for detection of parasite antigen floating in human blood, preferentially performed on a lateral flow format, rather than an ELISA format. Therefore, future selection of a good binding partner for either Nb1 or Nb19 will have to be performed as a continuation of the work presented here.
- Soluble egg antigen (SEA)
- schistosoma diagostic tool