PLoS Pathogens: Phagocyte Responses to Protozoan Infection and How Toxoplasma gondii Meets the Challenge

Toxoplasma and other tissue-invasive microbial pathogens encounter the innate immune system from the earliest stages of infection. Using genetically altered mice and parasites in combination, we are gaining fascinating insight into the molecular biology of the host-parasite interaction that plays out between Toxoplasma and the phagocytes of innate immunity. The overall theme emerging is that faced with a strong and multi-pronged host innate immune response, Toxoplasma does not retreat but actively engages cells of the innate defense system . Balancing stimulation of host defense with avoidance of immune elimination allows this extraordinary parasite to persist in its host and ensures widespread transmission throughout the vertebrate animal kingdom.