Development of monoclonal antibodies against PD-L1 and preliminary investigation on potential application in treatment of chronic hepatitis B virus in-fection
	    		
		   		
		   			
		   		
	    	
    	 
    	10.3969/j.issn.1000-484X.2016.07.016
   		
        
        	
        		- VernacularTitle:抗PD-L1单抗的研制及其对乙型肝炎病毒的抑制效果初步研究
 
        	
        	
        	
        		- Author:
	        		
		        		
		        		
			        		Yong WU
			        		
			        		;
		        		
		        		
		        		
			        		Tianying ZHANG
			        		
			        		;
		        		
		        		
		        		
			        		Liuwei SONG
			        		
			        		;
		        		
		        		
		        		
			        		Ningshao XIA
			        		
			        		;
		        		
		        		
		        		
			        		Quan YUAN
			        		
			        		
		        		
		        		
		        		
		        		
		        		
			        		
			        		
		        		
	        		
        		 
        	
        	
        	
        		- Publication Type:Journal Article
 
        	
        	
        		- Keywords:
        			
	        			
	        				
	        				
			        		
				        		PD-L1;
			        		
			        		
			        		
				        		Therapeutic monoclonal antibodies;
			        		
			        		
			        		
				        		HBV;
			        		
			        		
			        		
				        		Immunotherapy
			        		
			        		
	        			
        			
        		
 
        	
            
            
            	- From:
	            		
	            			Chinese Journal of Immunology
	            		
	            		 2016;32(7):1004-1008,1012
	            	
            	
 
            
            
            	- CountryChina
 
            
            
            	- Language:Chinese
 
            
            
            	- 
		        	Abstract:
			       	
			       		
				        
				        	Objective:To get specific monoclonal antibodies ( mAbs) against PD-L1 which can block PD-1/PD-L1 binding, and explore the feasibility of its application on the treatment of chronic HBV infection preliminarily by in vitro and in vivo model. Methods:E. coli expression and series chromatography purification system were employed to get human and mouse PD-1/PD-L1 that had binding activity in vitro. By immunizing BALB/c mouse with purified recombination proteins of PD-L1,mAb hybridoma cell lines against PD-L1 were obtained. The reactivity with human/mice PD-L1 of individual antibody and the interaction blocking activity of the mAbs to PD-1/PD-L1 in vitro were examined by indirect chemiluminescence immune assay. Results: 8 cell lines against PD-L1 were obtained and 2 Anti-PDL1 mAbs (Ab5 &Ab6) performed strong immune activity to human/mice PD-L1 and blocking activity to PD-1/PD-L1. In the PBMC stimulation experiment of chronic HBV patient,Ab5 and Ab6 could promote theγ-IFN levels. With HBV in-fecting mice model,intravenous injections of these mAbs induced dramatically decrease of HBV DNA copies about 20 times, HBsAg levels in serum reduced to 30% of the baseline level. Conclusion:We obtained 2 PD-L1 mAbs with the reactivity to human/mice PD-L1 and blocking activity to PD-1/PD-L1. The 2 mAbs can promote T cell function in PBMC stimulation culture of chronic HBV patient, have significant antiviral effect in HBV transgenic mice and can be candidates for immunotherapy applications.