Figure 4. The Spectrum of Costimulation from Adjuvants to Viruses.
A cellular and molecular understanding of dendritic-cell biology has facilitated improvements in vaccine-induced immune responses. Rather than generating responses through infection, immune stimulation can be achieved by increasingly complex modes of antigen presentation that range from introduction of selected proteins, with or without adjuvants, to gene-delivered immunogens, viruslike particles (VLP), structured arrays, or attenuated viruses. These approaches represent a spectrum of complexity and mimicry that elicits protective immunity without inflicting the adverse consequences of natural infection. HBV denotes hepatitis B virus, HPV human papillomavirus, VEE Venezuelan equine encephalitis, and WT wild type.