The Times has today (9 August 2012) covered a story about a potential role for the BCG vaccine in helping people with type 1. The story follows publication of an article in the journal PLoS One which claims to have shown benefit for a small number of people with long established type 1.
The study was led by Dr Denise Faustman of Massachusetts General Hospital, USA. Dr Faustman’s previous research in mice has shown that a molecule called TNF may help to turn off the immune response that leads to type 1 diabetes. As TNF cannot be safely administered to humans as a drug, the team have looked for other medications that can boost the body’s own levels of TNF. The BCG vaccine is known to increase levels of TNF in the body for a short time, so the team have conducted a small trial to see if this increase in TNF levels has an impact in people with type 1.
The study reported in the Times was published in the online journal PLoS One, and involved six patients. Three were given a placebo and three were given the BCG jab. Blood samples from two of the BCG patients showed that there was a small change in the balance between the ‘bad’ immune cells that target the insulin producing cells and the ‘good’ immune cells that work to supress autoimmune reactions in our bodies, for a short time after the trial. There was also evidence that the patients produced slightly more of their own insulin during this time. Unfortunately it was not enough to alter the way they managed their type 1. The same results were also seen in one of the patients who received the placebo, who had contracted a virus during the course of the study.