Â鶹Éçmadou

Research title: The use of whole genome sequencing of Acanthamoeba isolated from keratitis to identify new pathogenic factors and areas for development of new therapies.

Supervisor: Professor Mark Willcox

Joint-supervisor: A/ Professor Nicole Carnt

Research abstract:ÌýThe genus Acanthamoeba, one of a number of free-living amoeba, is a unicellular eukaryotic organism that can be widely distributed in a variety of environments. It can be transmitted to humans from these environmental reservoirs and is able to cause Acanthamoeba keratitis (infection of the cornea) that could lead to blindness. Despite the disease being relatively rare, contact lens users are at high risk of Acanthamoeba keratitis (AK), especially if water (domestic, river, sea, swimming pools etc) comes into contact with their contact lenses. The main problems with AK are the difficulties in its differential diagnosis from other causes of keratitis, and the difficulty in its treatment.

Acanthamoeba have two morphological forms in its life cycle, a trophozoite stage which is also known as the vegetative form is the metabolically active and pathogenic. Its double walled cyst stage is its dormant stage. As a cyst it is non-feeding, inactive but resistant to therapeutics and disinfection. It can enter into the cyst stage during keratitis. Species of Acanthamoeba were traditionally classified into three morphological groups I, II, and III based on the shape and size of their cysts. However, this morphological classification is not currently reliable as culture conditions can affect cyst morphology.

Twenty-three species and genotypes (T1–T20) ofÌýAcanthamoebaÌýhave been identified.Ìý Seven genotypes, T2, T3, T4, T5, T6, T11, T15, have been reported previously from Acanthamoeba keratitis. The T4 genotype, which includes A. castellanii and A. polyphaga, is most commonly found from AK and is prevalent in the environment.

Acanthamoeba can harbor endosymbiotic microbes. Strains with endosymbionts have been shown to be more pathogenic. Studies have only recently used molecular techniques to identify these endosymbionts, and my research will expand this knowledge, and test associations with pathogenicity in models of keratitis. The observation that blooms of Cyanobacteria can occur at the same time as increases in Acanthamoeba in water, suggests there may be interplay between these microbes, and I will also study whether cyanobacteria in particular can be endosymbionts and affect pathogenicity.

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Biography

I completed Bachelor of Science degree in Medical Laboratory Science in July 2009. Then, I received my Master of Science Degree in Medical Parasitology in July 2015. I was awarded an University International Postgraduate scholarship from the University of New South Wales in 2025, to study my PhD (described above).

Education

2025-Current: PhD candidate SOVS, Â鶹Éçmadou, Australia

2013-2015: Masters of Science Degree in Medical Parasitology, Department of Medical Parasitology, University of Gondar, Ethiopia

2006-July 2009: Bachelor of Science degree in Medical Laboratory Science, School of Biomedical and Laboratory Sciences, University of Gondar, Ethiopia

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Awards

University International Postgraduate Award (UIPA) at University of New South Wales, Australia (2025)