Researchers at the Ragon Institute’s System Serology Lab have conducted a comprehensive study on how infants develop immunity to Respiratory Syncytial Virus (RSV). Postdoctoral fellow Nadège Nziza was the first author of the study, published in Immunity, which explores how the immune responses of infants to RSV change over time.

The paper, titled “Longitudinal humoral analysis in RSV-infected infants identifies pre-existing RSV strain-specific G and evolving cross-reactive F antibodies,” provides a detailed analysis of the antibodies that infants produce when infected with RSV. The researchers found significant age-dependent differences in these immune responses.

In younger infants, maternal antibodies provide initial protection but wane after a few months, creating a window of vulnerability between 3 and 6 months of age. As infants grow older, they start developing their own antibodies, which become more specific and effective over time.

This research sheds light on the importance of both G-specific and F-specific antibodies in controlling RSV infections. G-specific antibodies, which are strain-specific, appear early and contribute to initial control, while F-specific antibodies, which are more cross-reactive, evolve later and are crucial for the resolution of the infection.

These findings offer valuable insights into the mechanisms of immune protection against RSV and underscore the need for age-targeted treatment strategies.