In a recent study, researchers from Stanford University School of Medicine have developed a new promising vaccination technique to treat type 1 diabetes.
Type-1 Diabetes is an auto immune disease in which the β cells responsible for insulin production are destroyed by the body’s immune system. This hinders the production of insulin thereby increasing the blood sugar level. At present there is no treatment available to completely cure type 1 Diabetes, which accounts for nearly 5% of diabetes cases in United States.
A team of researchers from Stanford University School of Medicine have developed a new DNA vaccine, which selectively inhibits the immune response that destroys the insulin producing cells. According Lawrence to Steinman, MD, professor of pediatrics and of neurology and neurological sciences at Stanford, this is a new technique where the vaccine acts to shut down a specific immune response unlike a conventional vaccine that triggers an immune response.
Immune cells differentiate healthy body cells from infectious microbes by identifying specific proteins on the cells. Vaccines, in general, are designed to boost the immune response against the specific proteins found on infectious microbes.
In this research, scientists modified the DNA containing the genetic code for proinsulin, a precursor of insulin, in such a way that the protein sends anti inflammatory signals to the immune cells targeting proinsulin. This methodology was found to suppress the auto immune response against the insulin producing β cells.
The randomized trial involved 80 patients who were randomly divided into five groups. Patients in the first four groups were vaccinated with different dosages every week for a period of 12 weeks, while the patients in the fifth group received placebo injections.
Researchers measured the levels of C-peptide, a part of proinsulin that remains in circulation following insulin production. As C-peptide remains in blood for a longer duration, it provides a better assessment of actual insulin production by the β cells.
The measurements were taken at baseline and at five and 15 weeks and six, nine, 12, 18 and 24 months after beginning the vaccination.
It was found that immune cells targeting proinsulin were drastically reduced without affecting the other immune cells in patients who received the vaccine. Moreover, no adverse reactions were reported due to the vaccine.
The effects of the vaccine began to wear off gradually once the dosage was discontinued after the study. Hence the lead author, Lawrence Steinman has indicated the need for further trials to prove the efficacy of the new promising vaccination technique among larger patient group.
Written by: Janet Grace Ortigas