Potential Vaccine Could Be Effective in Newborns After Birth
- By BSTQ Staff
Researchers at Boston Children’s Hospital have identified a potent compound that activates immune responses in newborns’ white blood cells substantially better than anything previously tested, and that could make vaccines effective right after birth. Due to newborns’ underdeveloped immune systems, they don’t respond to most vaccines, leaving them at high risk for infections like rotavirus, pertussis and pneumococcus. This potential vaccine would give physicians the ability to immunize infants at birth, rather than at 2 months of age, when most current vaccination series begin.
In their work, the researchers found that white blood cells have one receptor, the toll-like receptor 8 (TLR 8), that responds strongly to stimulation. They tested a panel of synthetic small-molecule compounds, known as benzazepines, that specifically target TLR 8. One benzazepine, VTX-294, produced a strong immune response in white blood cells from newborns (taken from cord blood samples), as well as whole blood from adults. The compound induced robust production of cytokines — chemicals that rally the immune response — and proved at least 10 times more potent than the best activator of TLR 8 known previously. It also triggered production of so-called co-stimulatory molecules that enhance immune responses. Even very low concentrations of VTX-294 strongly activated antigen-presenting cells, a type of white blood cell whose activation induces immune memory, which is key to effective responses to vaccines.
“This one receptor seems to lead to more adult-like responses — immediate, short-term responses that are more appropriate for fighting infections,” said David Dowling, PhD, co-first author on the study. “We’re excited about the benzazepines because they are already in the first clinical pipeline. That advances the potential for using them in a clinical study in human newborns once they have been proven safe in animal studies.”
The research was published in the March 4 edition of PLOS ONE.
