Abstract: Iron is an essential regulatory signal for virulence factors in many pathogens. Its sequestration by host cells (nutritional immunity) is an elaborate strategy to limit pathogenesis. How invading pathogens evade host-mediated iron sequestration is widely studied but the underlying mechanisms in African trypanosomes remain enigmatic. Trypanosomes are deeply diverged eukaryotic parasites of humans and livestock. They invade the bloodstream and various tissues relying exclusively on their hosts to satisfy their iron needs. In this talk, I will present data demonstrating that iron regulatory mechanisms in trypanosomes appear to have diverged significantly from their hosts. I will demonstrate that multiple systems of iron import in trypanosomes promote survival in both acute and chronic anaemic phases during an infection. Our overall goal is to identify differences in iron-stress response pathways that can direct future drug design.

Biography: Dr. Calvin Tiengwe is interested in understanding the mechanisms that regulate cellular iron homeostasis in Trypanosoma brucei, a “neglected” pathogen that causes African sleeping sickness in humans and a range of diseases in cattle, other livestock. He did his Ph.D. in Molecular Parasitology at the University of Glasgow with Dr. Richard McCulloch and Prof. Dave Barry studying nuclear DNA replication in T. brucei. After his Ph.D., he did two consecutive postdocs in the USA at Johns Hopkins Medical School (Paul Englund lab) and State University of New York at Buffalo (Jay Bangs lab). His current research has the potential of solving an important, long-standing fundamental question - are there alternative eukaryotic mechanisms for iron sensing and regulation of iron homeostasis in the African trypanosome, T. brucei?

https://www.imperial.ac.uk/people/c.tiengwe