Spleen-targeted nanosystems for immunomodulation

The spleen is the largest peripheral immune organ and greatly contributes to regulating immune responses. Selectively delivering immunoregulators, such as antigens, adjuvants, and small molecular inhibitors, to the spleen have exhibited great potential to prevent and/or treat immune-related diseases, such as cancers, infectious diseases, autoimmune diseases, and pathogenic inflammatory disorders. Many rationally designed nanosystems can be used for spleen-targeted delivery and show promising therapeutic effects. In this review, we described the architecture of the spleen, highlighted the rules for designing spleen-targeting nanosystems, and discussed their application in the enhancement or suppression of the immune response for disease treatment or prevention.