Researchers at Children's Hospital Boston may have found a way to boost newborns' immature immune systems, possibly making infections like respiratory syncytial virus, pneumococcus and rotavirus much less of a threat.
In the April 25 online edition of Blood, Ofer Levy, MD, PhD, in Children's Division of Infectious Diseases, reports uncovering an important difference between newborns' and adults' immune systems that involves Toll-like receptors (TLRs) on antigen-presenting cells. TLRs, which come in 10 varieties, detect infections and
trigger the release of cytokines, prompting T-cells to mount a defense.
Dr. Levy's team found that in newborns, most TLRs trigger very weak immune responses. But one variety, TLR8, responds robustly, spurring production of normal adult levels of the cytokines
TNF-alpha and IL-I2 and the immune stimulant CD40.
Dr. Levy speculates that TLR8 agonists, given as vaccine
adjuvants at birth, might protect newborns from infection. Several
biopharmaceutical firms are developing TL8 agonists as
immune stimulants, and Dr. Levy plans to test them in
animals and eventually in human infants.
