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Generation and characterization of the VP1 recombinant protein of the chicken anemia virus

The aim of this study is to obtain a VP1 recombinant protein of the chicken anemia virus, capable of specifically detecting antibodies in the blood sera of sick chickens. 
 
Materials and methods. Cloning of a fragment of the VP1 gene of an infectious anemia virus of chickens was performed in the expression plasmids pET15b and pGEX-3T in the context of reading the polyhistidine sequence and glutathione-S-transferase, respectively. The recombinant proteins 6HIS-ΔVP1 and GST-ΔVP1 expressed in E. coli Rosetta (DE3) strains were purified by metal affinity chromatography. Amino acid sequence of recombinant proteins was confirmed by mass spectrometry. The specificity of the interaction of recombinant proteins with polyclonal antibodies was determined by ELISA. The ability of the recombinant 6HIS-ΔVP1 protein to detect antibodies in field and blood sera of SPF chickens was evaluated by indirect ELISA. To control the specificity of the antigen, the immune sera of birds for viruses of infectious bronchitis, Newcastle disease, infectious laryngotracheitis, adenoviral infection, Mycoplasma gallisepticum, and negative serum of chickens were used. 
 
Results. The recombinant VP1 protein of chicken anemia virus containing a polyhistidine tag (6HIS-∆VP1) was obtained. It was shown that this recombinant protein is able to specifically detect antibodies in the blood sera of sick chickens. 
 
Conclusion. The obtained recombinant protein 6HIS-ΔVP1 can be used to detect antibodies to the chicken anemia virus in the serum of sick chickens, and can also be considered as a potential component of vaccines against this virus.