| Term 
 | Definition 
 
        | Single glycopeptide, A,B,C- codominant, inherit one of each subclass from each parent so there are 6 possibilities,all nucleated cells, endogenous antigen receptors, contain beta 2 microglobulins |  | 
        |  | 
        
        | Term 
 | Definition 
 
        | Antigens that originate outside the cell |  | 
        |  | 
        
        | Term 
 | Definition 
 
        | Two glycopeptide, DP,DQ,DR, more than 6 possible combinations, receptors for exogenous antigens, has alpha and beta chains |  | 
        |  | 
        
        | Term 
 | Definition 
 
        | Normal cell constituents or viral proteins generated during viral infection and replication within the cells |  | 
        |  | 
        
        | Term 
 | Definition 
 
        | Fragments of antigens are displayed on the cell surface as class I or Class II HLA molecules |  | 
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