School of Life Sciences

Her research interest is in proteolytic enzymes of African trypanosomes. African trypanosomiasis is a parasitic disease caused by haemoflagellate protozoa of the genus Trypanosoma that is spread by the bite of the tsetse fly. The human form of the disease, called sleeping sickness, is caused by T. brucei gambiense in eastern and central Africa and by T. brucei rhodesiense in eastern Africa. Livestock, notably cattle and goats, are susceptible to T. congolense and T. vivax, that causes nagana and the disease also occurs in northern KwaZulu-Natal and Mozambique. Wildlife do not show any symptoms, but act as reservoirs of the parasite, hence the large scale killing of animals in the 1920s to protect cattle in the area that now constitutes Hluhluwe-iMfolozi. As a result of the ability of trypanosomes to continuously change the expression of their variable surface glycoproteins (VSGs), there is no vaccine for trypanosomiasis, and resistance has developed against the prophylactic drugs in use for more than 50 years.
They study various cysteine and serine proteases of T. congolense and T. vivax with an aim to develop simple diagnostic tests, new chemotherapeutic agents, and a vaccine that could be used in resource-poor settings in sub-Saharan Africa. In addition to cloning, recombinant expression, purification, and enzymatic characterisation of the proteases, RNAi, and gene knock-out studies, they produce antibodies in chickens against the whole proteases and against peptides corresponding to epitopes identified in silico. Chicken egg yolk antibodies (IgY) are powerful immunochemical tools that find wide application in research, and we have established a number of collaborations around this capacity.