Development of an attenuated vaccine strain from a korean respiratory type infectious bronchitis virus.
	    		
		   		
	    	
    	
    	
   		
        
        	
        	
        	
        		- Author:
	        		
		        		
		        		
			        		Kang Seuk CHOI
			        		
			        		
			        		
			        			1
			        			
			        		
			        		
			        		
			        		
			        		;
		        		
		        		
		        		
			        		Woo Jin JEON
			        		
			        		;
		        		
		        		
		        		
			        		Eun Kyoung LEE
			        		
			        		;
		        		
		        		
		        		
			        		Soo Jeong KYE
			        		
			        		;
		        		
		        		
		        		
			        		Mi Ja PARK
			        		
			        		;
		        		
		        		
		        		
			        		Jun Hun KWON
			        		
			        		
		        		
		        		
		        		
		        		
		        			
			        		
			        		Author Information
			        		
		        		
		        		
			        		
			        		
			        			1. Avian Diseases division, Department of Animal and Plant Health Research, Animal, Plant and Fisheries Quarantine and Inspection Agency, Anyang 430-757, Korea. kchoi0608@korea.kr
			        		
		        		
	        		
        		 
        	
        	
        	
        		- Publication Type:Original Article
 
        	
        	
        		- Keywords:
        			
	        			
	        				
	        				
			        		
				        		attenuation;
			        		
			        		
			        		
				        		infectious bronchitis;
			        		
			        		
			        		
				        		live vaccine;
			        		
			        		
			        		
				        		protection
			        		
			        		
	        			
        			
        		
 
        	
            
            	- MeSH:
            	
	        			
	        				
	        				
				        		
					        		Chickens;
				        		
			        		
				        		
					        		Eggs;
				        		
			        		
				        		
					        		Humans;
				        		
			        		
				        		
					        		Infectious bronchitis virus;
				        		
			        		
				        		
					        		Korea;
				        		
			        		
				        		
					        		Massachusetts;
				        		
			        		
				        		
					        		Ovum;
				        		
			        		
				        		
					        		Parents;
				        		
			        		
				        		
					        		Point Mutation;
				        		
			        		
				        		
					        		Sprains and Strains;
				        		
			        		
				        		
					        		Vaccination;
				        		
			        		
				        		
					        		Viral Load;
				        		
			        		
				        		
					        		Viruses
				        		
			        		
	        			
	        			
            	
            	
 
            
            
            	- From:Korean Journal of Veterinary Research
	            		
	            		 2011;51(3):193-201
	            	
            	
 
            
            
            	- CountryRepublic of Korea
 
            
            
            	- Language:Korean
 
            
            
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		        	Abstract:
			       	
			       		
				        
				        	An attenuated vaccine strain AVR1/08 of Korean respiratory type of infectious bronchitis virus (IBV) was developed by 89th passages of IBV D85/06 strain in chicken eggs. The AVR1/08 strain had higher virus titer at least 20 times (10(1.3)) than the parent virus D85/06 by egg inoculation method. The AVR1/08 strain had a single point mutation (S to Y) at position 56 of spike protein of IBV compared to parent virus IBV D85/06 strain. The mutation was observed consistently at viruses after 47th passage in chicken eggs. The AVR1/08 strain showed no virulence even after 6 passages in chickens and all chickens inoculated induced anti-IBV antibody 14 days after vaccination. The AVR1/08 strain had broad protective efficacy against QX type Korean nephropathogenic virus (Q43/06 strain), KM91 type Korean nephropathogenic virus (KM91 strain) and Korean respiratory virus (D85/06 strain). In contrast, Massachusetts (Mass) type attenuated vaccine strain H120 showed protection of 37.5 to 50% against these three viruses. Our results indicate that the AVR1/08 strain has potential as an attenuated vaccine effective in controlling IBVs circulating in Korea.