However, further studies with more samples from additional populations will be necessary to evaluate the status ofB

However, further studies with more samples from additional populations will be necessary to evaluate the status ofB. detection of the anti-B. bovis-specific antibody. Such a test would have great benefits in large-scale epidemiological studies and lead to eradication. Until now, many serological checks have been utilized for the analysis ofBabesiainfection in cattle, such as the indirect immunofluorescent-antibody test (IFAT) and the enzyme-linked immunosorbent assay (ELISA) (3,26). IFAT has been widely used for the detection of the anti-B. bovisantibody; however, besides not becoming particularly sensitive, IFAT is definitely unsuitable for use with a large number of serum samples. Furthermore, the results of IFAT may be affected from the subjective view of the operator (3,30). In contrast, ELISA is quite sensitive and may become very easily used to test large numbers of samples (3,26). ELISA offers previously been evaluated for the detection of antibodies toB. bovisby use of a native antigen. Its potential ability has been demonstrated to be a powerful tool for serological studies (2,8,16,27), but the poor quality of antigens and the cross-reaction withB. bigeminahave impeded its software (3,9,26). Recently, an ELISA based on a recombinant antigen has been significantly developed (2,10,31) because it gives two major advantages: there is a negligible batch-to-batch variance in the antigen and there is no need to destroy experimental animals for preparation of the native antigen (2). TheB. bovisrhoptry-associated protein 1 (RAP-1) gene encoding a 60-kDa merozoite apical membrane polypeptide was recognized by Suraez et al. (23). The function of RAP-1 is definitely poorly recognized, but it is definitely believed that rhoptry proteins play an important role in sponsor cell invasion (21,22). The major Docusate Sodium immunogenic B-cell and T-cell epitopes on RAP-1 are conserved among all strains tested, but they are not conserved between different varieties (5,24). The lack of extensive variations in RAP-1 among geographically unique isolates ofB. bovissuggests that Docusate Sodium RAP-1 should be considered a candidate antigen in the development of a diagnostic reagent and subunit vaccine (4,7,19). In this study, the gene encodingB. bovisRAP-1 was indicated in insect cells by using a baculovirus manifestation system. Then, the ELISA based on the Docusate Sodium recombinant antigen was developed, and its potential use for the detection of antibodies toB. bovisin cattle was evaluated. == MATERIALS AND METHODS == == Parasites. == B. bovisstrain Texas was continually cultured with bovine erythrocytes by using a microaerophilous stationary-phase culturing system (15). When the level of parasitemia reached 5 to 10%, the infected erythrocytes were Rabbit Polyclonal to YB1 (phospho-Ser102) washed three times with phosphate-buffered saline (PBS), and the pellets were stored at 80C. == Cloning of RAP-1 gene. == B. bovis-infected erythrocyte pellets were suspended inside a DNA extraction buffer (100 mM Tris-HCl [pH 8.0], 1% sodium dodecyl sulfate [SDS], 0.1 M NaCl, 10 mM EDTA) and digested with proteinase K (100 g/ml) for 2 h at 55C. The genomic DNA was then extracted with phenol-chloroform and precipitated with ethanol. The DNA pellets were suspended in TE buffer (10 mM Tris-HCl [pH 8.0], 1 mM EDTA) and used like a DNA template for any PCR. The entire RAP-1 gene was amplified by PCR with two primers, 5-ACGGATCCGACAATGAGAATCATT-3 and 5-ACGGATCCAAACGCATCTCATCAG-3, both of which contained aBamHI site in the 5 end (23). The PCR was performed in 100 1 of a reaction mixture comprising 100 pmol of each primer, 0.5 g of template DNA, 20 M of a mixture of deoxynucleoside triphosphates, 10 l of a.