RT Journal Article SR Electronic(1) A1 Song, Chang-Seon A1 Lee, Youn-Jeong A1 Lee, Chang-Won A1 Sung, Hwan-Woo A1 Kim, Jae-Hong A1 Mo, In-Pil A1 Izumiya, Yoshihiro A1 Jang, Hyung-Kwan A1 Mikami, TakeshiYR 1998 T1 Induction of protective immunity in chickens vaccinated with infectious bronchitis virus S1 glycoprotein expressed by a recombinant baculovirus. JF Journal of General Virology, VO 79 IS 4 SP 719 OP 723 DO https://doi.org/10.1099/0022-1317-79-4-719 PB Microbiology Society, SN 1465-2099, AB A recombinant baculovirus containing the S1 glycoprotein gene of the virulent nephropathogenic KM91 strain of infectious bronchitis virus (IBV) was constructed in order to investigate protective immunity in vaccinated chickens. Results from the protection test were evaluated by re-isolation of virus from the kidneys and tracheas of vaccinated chickens after challenge with strain KM91. After three immunizations, the recombinant S1 (rS1) glycoprotein induced 50% protection of the kidney, whilst inactivated KM91 induced 88% and 50% protection of the kidney and trachea, respectively. In chickens primed with the attenuated H120 vaccine strain, which is heterologous to KM91, the rS1 glycoprotein induced 83% protection of the kidney after two immunizations. Haemagglutination-inhi-bition titres were also increased in chickens immunized with the rS1 glycoprotein after three immunizations, and significantly higher titres were detected after challenge. These data indicate that the expressed rS1 glycoprotein alone can induce a protective immune response as well as an antibody response., UL https://www.microbiologyresearch.org/content/journal/jgv/10.1099/0022-1317-79-4-719