This clinical trial studies the immune system response to pneumococcal vaccines in different groups of people, including young healthy adults, older adults, and people living with HIV. The study will examine how two different types of pneumococcal vaccines – Prevenar 20 and Pneumovax 23 – affect the formation of special structures in lymph nodes called germinal centers, which are important for immune system function.
The study involves taking small samples from lymph nodes and blood to analyze how the immune system responds to vaccination. Participants will receive a single dose of one of the pneumococcal vaccines through an intramuscular injection. The researchers will monitor the immune response for up to 6 months after vaccination by collecting blood samples and small amounts of saliva.
The research aims to understand how factors like age and HIV infection influence the body’s response to different types of vaccines. This knowledge could help improve vaccination strategies for different groups of people. The study will also look at how lifestyle factors such as diet, exercise, and smoking might affect the immune response to vaccination.



The Netherlands