March 5, 2009

expert comments on new research into type 1 diabetes, as published in two papers in Diabetologia and Science Express

New research suggests a link between enteroviral infection of the pancreatic beta cells and the development of type 1 diabetes, creating a possible avenue for the development of a vaccine.

Prof Mark Peakman, Department of Immunobiology, King’s College London School of Medicine, said:

“The ‘viral hypothesis’ for type 1 diabetes was first mooted some decades ago. Since then a large number of studies have added some substance to the story, but without necessarily nailing it. I think with recent advances, of which the two studies coming out today are good examples, we are inching closer to understanding whether and how viruses contribute to this disease.

“The Noel Morgan study is hugely significant because for the first time we have a large enough study of pancreas post mortem samples from patients who died near to diagnosis – this has been lacking and therefore we have had to rely on the odd case report. The Morgan study shows that when you do a cross sectional study, enterovirus infection is a relatively common event, and that it appears to infect the pancreatic islets preferentially. The fact that it is found more commonly in patients with type 1 diabetes suggests either (i) that they are more susceptible to infection or persistence or (ii) that the infection somehow tips them over the edge and into clinical diabetes (we know that the processes that lead to diabetes take several years to reach the end-stage, when patients cannot control blood glucose).

“The genetic study, coming at the same time, is therefore another significant step forward. It now says that if you possess a particular variant of a gene that is known from animal studies to be an important early protection mechanism against viruses such as enterovirus, you have a higher risk of getting type 1 diabetes.

“Combined, the two studies are hugely important in our understanding of the ‘viral hypothesis’. What are its implications? Better understanding of why/how the disease arises, obviously. If the virus proves to be an important trigger, could we even contemplate a vaccine to protect against it?”