Immunization of Bos taurus Steers with Babesia bovis Recombinant Antigens MSA-1, MSA-2c and 12D3

Abstract

The purpose of this research was to evaluate the recombinant proteins MSA-1, MSA-2c and 12D3 as a combined immunogen for cattle. Fifteen steers were randomly assigned into three groups of five animals each (I, II and III). On day 0, cattle in group I were injected with 50 microg each of rMSA-1, rMSA-2c and r12D3 with the adjuvant Montanide 75; cattle in Group II received adjuvant-PBS, and Group III were untreated controls. On day 14, cattle in Group I received a second injection of the three recombinant proteins in adjuvant and cattle in Group II again received adjuvant alone. On day 28, all groups of cattle were challenged with a field strain of Babesia bovis. After challenge, the experimental cattle were clinically and serologically monitored. Three of the five steers immunized with the combined recombinant B. bovis proteins seroconverted on day 14 post-immunization (P.I.) and the maximum titre was 1 : 1600. All five immunized steers presented strong seropositivity to B. bovis antigens at day 21 P.I. The prepatent periods of vaccinated cattle were delayed until day 10 post-challenge exposure versus 8 and 7 days in Groups II and III, respectively. Cattle in all groups had fever above 41 degrees C; the reduction in packed cell volume was not significantly different (P > 0.05) in vaccinated group I compared with Groups II and III (29% versus 26% and 31%, respectively). Treatment was required for one steer in the control group. During the period of the study, the weight of cattle in Groups I and II increased an average of 9 and 7 kg, whereas the weight of the control cattle was reduced on average 4 kg. Immunization with rMSA-1-rMSA-2c-r12D3 proteins was not sufficient to prevent clinical symptoms against challenge, but the immunologic response was sufficient to protect steers against a mild virulent strain of B. bovis.

The Genetic Diversity of Merozoite Surface Antigen 1 (MSA-1) among <i>Babesia bovis</i> Detected from Cattle Populations in Thailand, Brazil and Ghana

“…bovis based on recombinant antigens [3, 11, 12, 22]. The merozoite surface antigens (MSAs) were considered to be good vaccine candidate, as the antisera raised against the recombinant forms of these antigens blocked the erythrocyte invasion of B .…”

Comparative Study of Indirect Fluorescent Antibody, ELISA, and Immunochromatography Tests for Serological Diagnosis of Bovine Babesiosis Caused by Babesia bovis

“…[ 7 , 30 ]. These tests are not useful for diagnosing bovine babesiosis during the clinical phase of the disease but are used for epidemiological studies or to evaluate antibabesial antibody titers after cattle vaccination [ 4 , 7 , 24 , 30 , 31 ]. The IFAT provides adequate sensitivity and is easy to perform [ 12 ]; however, it has some disadvantages in the analysis of samples, such as the low number that can be performed per day, depending on the operator’s ability and expertise, and the results are influenced by the subjective judgment of the analyst [ 32 ].…”

“…Babesia bovis recombinant merozoite surface antigen 1 (rMSA-1) was expressed and prepared as previously described [ 24 ]. Briefly, transformed E. coli TOP10 cells containing the recombinant pBAD/ThioTOPO®, (ThermoFisher Scientific, Waltham, MA, USA) plasmid inserted with the msa-1 gene were resuspended in lysis solution containing sarcosyl (0.03%) and protease inhibitors DNase and RNase and incubated for 3 h at room temperature with gentle agitation.…”

“…Briefly, transformed E. coli TOP10 cells containing the recombinant pBAD/ThioTOPO®, (ThermoFisher Scientific, Waltham, MA, USA) plasmid inserted with the msa-1 gene were resuspended in lysis solution containing sarcosyl (0.03%) and protease inhibitors DNase and RNase and incubated for 3 h at room temperature with gentle agitation. The recombinant B. bovis MSA-1 protein was recovered using a Pro-Bond Purification System on nickel-charged Ni-NTA affinity resin (ThermoFisher Scientific, Waltham, MA, USA) according to the manufacturer instructions, and purification quality was analyzed by electrophoresis in 12% polyacrylamide gels [ 10 , 24 ]. Finally, the rMSA-1 was dialyzed against PBS (pH 7.4) and concentrated using Amicon 50K MWCO filters (Corning, Tewksbury, MA, USA).…”

An Overview of Current Knowledge on in vitro Babesia Cultivation for Production of Live Attenuated Vaccines for Bovine Babesiosis in Mexico

“…It has been shown that these recombinant proteins generate high antibody titers in immunized cattle that are capable of inhibiting parasite invasion in vitro . However, in vivo trials demonstrated lack of protection against parasite challenge with field isolates ( 40 , 41 ). Moreover, cattle immunized with a multi-epitope modified vaccinia Ankara virus and recombinant proteins were not protective after challenging by a virulent B. bovis strain ( 41 ).…”