Seeing the invisible
In 2007 Helen Saibil was at a conference in Australia. Amongst the presentations there happened to be talks on the parasites malaria and toxoplasma and how they infect mammalian cells, causing disease. Helen is a structural biologist and whilst listening she began to realise that her newly acquired skills -she was doing electron tomography of cells- might allow the researchers to see things they had never seen before.
Electron tomography reveals structures in the interiors of cells in great detail. What she hoped was that it could be used to look at the malaria parasites inside red blood cells [See images below] to get a better understanding of what they do there. Helen approached one of the speakers, Mike Blackman, then at the National Institute for Medical Research at Mill Hill in London, and so began a thriving collaboration. One that has produced the remarkable pictures of malaria parasites breaking out of infected human red blood cells on this page.
Helen Saibil and her colleagues used electron tomography to peer into malaria infected cells, looking at the parasites hiding and multiplying inside. The technique produces exquisitely detailed pictures able to reveal very tiny features, but it has one big drawback. Electrons cannot penetrate deep into the sample so it only works on very thinly sliced samples, much thinner than an individual cell. As a result it cannot be used to look at entire cells, or in this case red blood cells containing malaria parasites.