1. CSIR Biosciences, P.O. Box 395, Pretoria 0001, South Africa
2. Elevation Biotech, 8 Blackwood Avenue, Parktown, Johannesburg 2193, South Africa
3. Department of Molecular Medicine and Haematology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg 2193, South Africa
4. Electron Microscope Unit, University of Cape Town, Rondebosch 7701, South Africa
5. Department of Medicine, Groote Schuur Hospital and University of Cape Town, Cape Town, South Africa