Newborn babies' immune system stronger than previously believed

Scientists have found that the immune system of newborn babies is actually stronger than what was believed earlier.

According to a new study led by King's College London, newborn immune T cells might have the ability to trigger an inflammatory response to bacteria. Although their immune system works very differently to that of adults, babies may still be able to mount a strong immune defense,

Till now, it was generally believed that babies had an immature immune system that didn't trigger the same inflammatory response normally seen in adults. Although babies need to protect themselves from the harmful pathogens they are exposed to from birth, it was thought that their T cells were suppressed to some extent to prevent inflammatory damage to the developing child.

However, the team discovered that whilst T cells in newborn babies were largely different to those in adults, it wasn't because they are immune-suppressed; rather, they manufactured a potent anti-bacterial molecule known as IL8 that hadn't previously been considered a major product of T cells, and that activated neutrophils to attack the body's foreign invaders.

The T cell activity could become a target for future treatments aimed at boosting the immune system of neonates in intensive care, where infection was a major risk for morbidity and mortality. Premature babies are also at serious risk of developing inflammatory diseases such as necrotising enterocolitis (NEC), where severe inflammation destroys tissues in the gut. NEC is the most common gastrointestinal surgical emergency in preterm babies, with mortality rates of around 15 to 30 per cent in the UK.

The study is published in the journal Nature Medicine.