Vaccine May Help Type 1 Diabetes
Immunotherapy with Bacillus Calmette-Guerin (BCG), a vaccine that stimulates tumor necrosis factor (TNF), was effective in killing off disease-causing autoimmune cells and improving insulin sensitivity and could serve as a possible treatment for long-term type 1 diabetes.
The genetic vaccine works by triggering innate immune response and inducing the production of TNF, which kills autoimmune T lymphocytes (which destroy beta cells, causing diabetes) while leaving healthy T cells untouched, says Denise Faustman, MD, PhD, of Harvard, and colleagues.
In a proof-of-concept, double-blind study, researchers randomly assigned 6 participants with long-term diabetes to injections of either BCG or placebo and compared results with 57 reference patients with diabetes, and 16 without the disease.
Weekly blood samples were taken, and after 20 weeks all participants who received BCG injections had increased levels of dead insulin-autoreactive T cells. BCG-treated subjects each had more than 50% of their C-peptide values above the 95th percentile of the reference subjects.
In low doses, the vaccine "ameliorates the advanced autoimmune process underlying type 1 diabetes by stimulating TNF, which selectively kills only disease-causing cells,” researchers concluded.
Faustman D, Wang L, Okubo Y, et al. Proof-of-Concept, Randomized, Controlled Clinical Trial of Bacillus-Calmette-Guerin for Treatment of Long-Term Type 1 Diabetes. PLoS ONE. 7(8): e41756. doi:10.1371/journal.pone.0041756 Published August 8, 2012. Accessed August 9, 2012