Baseline immune reprogramming under chronic pathogen exposure: mechanisms and implications for immune function

Vaccines do not work equally well in everyone. One possible reason is that our immune systems are shaped by the infections we experience throughout our lives. People living in different parts of the world are exposed to different combinations of infectious diseases, and these experiences may influence how their immune systems respond to vaccines.

This project investigates how lifelong exposure to infectious diseases shapes the human immune system and whether this contributes to differences in vaccine responses between populations. It compares African populations with differing levels of infectious disease exposure and examines immune responses in African and North American participants who received an experimental Human Immunodeficiency Virus (HIV) vaccine designed to stimulate protective antibody responses.

The study combines several approaches, including measuring antibodies in blood, studying immune cell activity, and analysing gene expression to build a detailed picture of the immune system before and after vaccination. By integrating these different types of data, it aims to identify immune characteristics associated with stronger or weaker vaccine responses.

The findings will improve understanding of why vaccines can perform differently in diverse populations and provide evidence to support the development of more effective and globally representative vaccines. Ultimately, this work aims to contribute to more equitable vaccine development and improved global health outcomes.