In<unk> , sub-optimal<unk> es (the blue Y-shaped structures in the graphic) bind to both viruses and Fc gamma receptors (labeled FcγRII) expressed on immune cells, promoting infection of these cells.<unk>  <unk> , sometimes less precisely called immune<unk>  or disease<unk> , is a phenomenon in which binding of a virus to suboptimal<unk> es enhances its entry into host cells, followed by its replication. The suboptimal<unk> es can result from natural infection or from vaccination.<unk>  may cause enhanced respiratory disease, but is not limited to respiratory disease. It has been observed in HIV, RSV virus and Dengue virus and is monitored for in vaccine development.
Antibody-dependent enhancement
Cross-tolerance
Reverse tolerance
Peripheral tolerance
Immune tolerance
Central tolerance
Desensitization 
Sensitization 