Efficacy and Immunogenicity of Recombinant Pichinde Virus-Vectored Turkey Arthritis Reovirus Subunit Vaccine

Abstract

We created a recombinant live pichinde virus-vectored bivalent codon optimized subunit vaccine that expresses immunogenic Sigma C and Sigma B proteins of turkey arthritis reovirus. The vaccine virus could be transmitted horizontally immunizing the non-vaccinated pen mates. The vaccine was tested for efficacy against homologous (TARV SKM121) and heterologous (TARV O'Neil) virus challenge. Immunized poults produced serum neutralizing antibodies capable of neutralizing both viruses. The vaccinated and control birds showed similar body weights indicating no adverse effect on feed efficiency. Comparison of virus gene copy numbers in intestine and histologic lesion scores in tendons of vaccinated and non-vaccinated birds showed a decrease in the replication of challenge viruses in the intestine and tendons of vaccinated birds. These results indicate the potential usefulness of this vaccine.

Keywords: Turkey arthritis reovirus; histologic lesion scores; live virus vaccine; recombinant vaccine; serum neutralizing antibodies; subunit vaccine.

Figure 1

(A) SN Ab titer of the vaccinated and sentinel birds against the homologous TARV SKM121 virus; (B) SN Ab titer of the vaccinated and sentinel birds against TARV O’Neil virus; (C) BW of birds from respective groups at 28 doa; (D) BW of birds from respective groups at 35 doa. Box plots with different letters have significant differences at p < 0.05.

Figure 1

(A) SN Ab titer of the vaccinated and sentinel birds against the homologous TARV SKM121 virus; (B) SN Ab titer of the vaccinated and sentinel birds against TARV O’Neil virus; (C) BW of birds from respective groups at 28 doa; (D) BW of birds from respective groups at 35 doa. Box plots with different letters have significant differences at p < 0.05.

Figure 1

(A) SN Ab titer of the vaccinated and sentinel birds against the homologous TARV SKM121 virus; (B) SN Ab titer of the vaccinated and sentinel birds against TARV O’Neil virus; (C) BW of birds from respective groups at 28 doa; (D) BW of birds from respective groups at 35 doa. Box plots with different letters have significant differences at p < 0.05.

Figure 2

Virus gene copy numbers in birds from respective groups in (A) intestine at 21 doa; (B) intestine at 28 doa; (C) tendons at 21 doa; (D) tendons at 35 doa. Box plots with different letters have significant differences at p < 0.05.

Figure 2

Virus gene copy numbers in birds from respective groups in (A) intestine at 21 doa; (B) intestine at 28 doa; (C) tendons at 21 doa; (D) tendons at 35 doa. Box plots with different letters have significant differences at p < 0.05.

Figure 2

Virus gene copy numbers in birds from respective groups in (A) intestine at 21 doa; (B) intestine at 28 doa; (C) tendons at 21 doa; (D) tendons at 35 doa. Box plots with different letters have significant differences at p < 0.05.

Figure 3

Histologic lesion scores in tendons of birds from respective groups at (A) 28 doa; (B) 35 doa. Box plots with different letters have significant differences at p < 0.05.