Preliminary analysis of recombinant β-tubulin of Pseudocohnilembus persalinus (Ciliophora: Scuticociliatida) as a vaccine antigen candidate against scuticociliatosis

The recombinant p-tubulin of Pseudocohnilembus persalinus was investigated to test whether tubulin could be a suitable antigenic target against scuticociliatosis. The cDNA of P persalinus beta-tubulin has an open reading frame of 1332 bp and had 15 TAA triplets code for glutamine (Q). All 15 TAA/Q triplets of the p-tubulin cDNA were mutated to universal CAA/Q triplets by site-directed mutagenesis and the mutated beta-tubulin was expressed in Escherichia coli as a fusion with glutathione S-transferase (GST-BTU). In Western blot analysis, rat sera immunized with recombinant GST-BTU reacted with reduced beta-tubulin of P persalinus. The immunized rat sera showed higher parasiticidal activity than those of control. Ciliates preincubated with heat-inactivated immune sera showed significantly lower proliferation than ciliates preincubated with control sera when exposed to naive rat sera as a complement source. The present results suggest that the recombinant beta-tubulin of scuticociliates may be used as a target antigen for development of vaccine against scuticociliatosis. (c) 2006 Elsevier B.V. All rights reserved.