Principal Investigator Jeroen Saeij
oxoplasma gondii is an obligate intracellular parasite capable of infecting virtually any warm-blooded animal. In humans, Toxoplasma infections are widespread (~between 20-85% of humans are chronically infected, depending on the region) and can lead to severe disease (toxoplasmosis) in individuals with an immature (fetus) or suppressed immune system (AIDS patients). The life cycle of Toxoplasma is complex and includes both sexual and asexual stages. While the sexual cycle is limited to the gut of felines, the asexual cycle can occur in a wide range of hosts and has two major forms: the rapidly growing tachyzoite and the slowly growing encysted bradyzoite. Bradyzoite cysts can persist within the infected tissue for the life of the host, hidden from the immune system and anti-parasitic drugs. In addition to studying Toxoplasma biology in order to develop anti-Toxoplasma agents, researchers are studying Toxoplasma as an important model of the pathogenesis of other disease-causing Apicomplexan parasites such as Plasmodium (malaria), and Cryptosporidium parvum, another opportunistic pathogen associated with AIDS.