Differential gene expression in peripheral blood mononuclear cells from children immunized with inactivated influenza...

Area of Science:

• Immunology
• Transcriptomics
• Vaccinology

Background:

• The immune response to inactivated influenza vaccines is complex and influenced by host factors.
• Understanding post-vaccination molecular changes in children is crucial for assessing vaccine efficacy and safety.

Purpose of the Study:

• To identify and characterize transcriptomic alterations in peripheral blood mononuclear cells (PBMCs) of children after inactivated influenza vaccination.
• To investigate how age and prior vaccine history impact these molecular responses.

Main Methods:

• Blood samples were collected from children before and 3 or 7 days after receiving the 2016-2017 quadrivalent inactivated influenza vaccine.
• RNA sequencing was performed on PBMCs to analyze gene expression.
• Differential gene expression analysis was conducted, comparing time points and stratifying by age and vaccine history.

Main Results:

• A significant number of differentially expressed genes (DEGs) were observed at both 3 and 7 days post-vaccination.
• Early (Day 3) changes were dominated by innate inflammation and apoptosis pathways, while later (Day 7) changes involved cellular processes and immunoglobulin gene expression.
• Older children showed increased inflammatory gene expression at Day 3. Prior vaccination history modulated responses, including decreased phagosome and dendritic cell maturation.

Conclusions:

• Post-inactivated influenza vaccination transcriptomic responses in children are dynamic and significantly influenced by the timing of sample collection, age, and previous vaccination status.
• These findings provide a temporal molecular map of the immune response to influenza vaccination in pediatric populations.