BCG, a vaccine weapon against tuberculosis, has a decreasing effectiveness over time. The blocking of a protein simultaneously with the administration of the vaccine has made it possible, in the laboratory, to improve long-term immune memory.
- 10 million people are infected with tuberculosis each year and 1 million die from it
- The BCG vaccine is one of the weapons to prevent the disease
- To compensate for the diminishing effectiveness of BCG over time, researchers used an antibody that blocks the IL-10 protein.
It is undoubtedly one of the most widely used vaccines in the world. But BCG, given to children to protect them from tuberculosis, sees its effectiveness diminish over time. Researchers from the Texas Biomedical Research Institute have just demonstrated in an animal model that adding an antibody to this vaccine would considerably improve its long-term effectiveness. Their work has been published in the Journal of Immunology.
The effectiveness of BCG decreases over the years
Tuberculosis kills a million people each year and more than 10 million are infected with Koch’s vacille, a microbacterium that primarily attacks the lungs. Weapons against this disease: antibiotics to treat, but above all a vaccine, the famous BCG, to prevent. Unfortunately, the effectiveness of this widely used vaccine to protect children wanes over the years. A peculiarity that scientists are trying to overcome.
To achieve this, the author of the work from Texas Biomedical Research, Joanne Turner, became interested in a molecule, interleukin-10 (IL-10), and its role in tuberculosis: if it helps to attenuate the Infection-related inflammation, IL-10 can also, according to Joanne Turner; do more harm than good and even cause TB infection. Hence the idea of blocking and eliminating IL-10, which has the effect of better controlling tuberculosis. But especially the idea of blocking IL-10 at the same time as the administration of the BCG vaccine.
An antibody that blocks IL-10
For this, the research team used an antibody which targets the host and not the pathogen and which blocks IL-10. In animal models, this system has made it possible to better control the tuberculosis infection. “By briefly blocking IL-10 at the same time as the vaccine is given, it allows this vaccine and the immune system to do their job creating long-lasting memory immune cells.“, explains Joanne Turner who adds: “We are very pleased to be able to reverse the diminishing efficacy of BCG by combining it with host-directed therapy in a single dose, making it very practical for the clinic.“.
It is now, after these promising results in laboratory experiments on mice, to see if this combination is effective in non-human primates. Before considering clinical trials on humans.
.
