Professor William Trager Ph.D.

Professor William Trager, a protozoologist and an authority on tropical medicine and insect physiology, is a leader in the fight against malaria, the most prevalent disease in the world today. In 1976, he and a colleague described a practical method for the continuous cultivation of Plasmodium falciparum, the most highly pathogenic human malaria parasite. Adopted by laboratories around the world, this method has given rise to a spectrum of physiological, biochemical, immunological, and genetic studies that were previously impossible or prohibitively difficult, opening the way for scientists working to develop an effective malaria vaccine. P. falciparum cultures have also advanced work on malarial drug resistance and efforts to screen for new types of antimalarial compounds.
Dr. Trager’s malaria reseach began 60 years ago, when he provided the first direct evidence of the significance of nutritional factors in the host’s susceptibility to malaria. Since then, he has shown that intracellular parasites lack certian biosynthetic pathways and depend on their host cells for cofactors essential to their own metabolism. His laboratory provided the first demonstration of the fine-structural relationship between malaria parasites and their host red cells. They also elucidated the cellular and physiological basis for the relative resistance to malaria conferred by the sickle haemoglobin gene. Recently, they achieved axenic cultivation of P. falciparum, obtaining extracellular development of the complete erythrocytic cycle work that may permit new research on the nature of the parasite’s dependence on its host. Methods developed for extracellular cultivation of P. falciparum may also be applicable to other parasites that have resisted cultivation including other human malaria parasites.
Other contributions include early studies on the nutritional needs of the larvae of Aedes aegypti, the yellow fever vector; demonstration of the mechanism of acquired immunity to ticks; and development of cultivation methods for a principal trypanosomal parasite of cattle.
Malaria affects an estimated 270 million people and kills more than one million, mostly children, each year. Primarily a disease of the Tropics, in today’s mobile world malaria poses a potential threat to individuals of every continent. Treatment, where available, is becoming increasingly complicated by the emergence of drug-resistant parasites.
Reflecting its status as one of humankind’s leading health concerns, malaria is a focus of research in laboratories around the world, Where scientists are making progress in efforts to understand the daunting complexities of the parasite and devise effective measures against it. Much of this progress has been made possible by the work of Dr. William Trager. In the mid-1970s, Dr. Trager’s development of a simple method for maintaining P. falciparum in continuous culture removed a major stumbling block and set the stage for a new era in malaria research. By providing access to all of the asexual erythrocytic stages of the parasite, as well as the stages that initiate infection in mosquitoes, this method opened key avenues for exploration and significantly accelerated the pace of malaria research.
In particular, the in vitro cultivation of P. falciparum was an essential first step in all efforts to develop an effective vaccine. This culture method has also allowed the study of malarial drug resistance and, more recently, has facilitated the use of newly developed molecular techniques to study the genetics of the parasite. Dr. Trager’s achievement has greatly enabled biomedical researchers to bring the tools of modern science to bear against an ancient foe.
Professor William Trager graduated with a B.S. from Rutgers University and received a Ph.D. from Harvard University. He spent his entire professional career at the Rockefeller University where he became a Professor Emeritus in 1980 and remains active as head of the laboratory of parasitology.