Host cell traversal by Plasmodium parasites drives sterilizing T cell-mediated immunity following immunization.

Active migration of Plasmodium sporozoites through host cells is essential for sterilizing T cell-mediated immunity in rodent vaccination models.

• Why it matters: Understanding what makes a malaria vaccine effective is crucial for developing strategies that achieve complete protection and aid global eradication efforts.
• What they did: The study used rodent models to show that sporozoite traversal through multiple host cells before infecting hepatocytes is necessary for inducing durable liver-resident memory CD8 T cell responses, independent of intrahepatic development.
• The result: Impaired cell traversal prevents protective T cell responses but not antibody production, indicating parasite behavior traits are key to eliciting sterilizing cellular immunity beyond intrahepatic parasite growth.