Dissecting the immune effector responses of macrophages in response to pathogens during early life and adulthood

Abstract

Different clinical outcomes are often observed in children and adults with infectious diseases. However, the precise mechanism of such phenomenon remains unknown. This study aims to investigate how the innate immune response of children and adults would differ towards different pathogens. Specifically, the effector functions, namely phagocytosis, cytokines production and reactive oxygen species (ROS) production would be compared between bone marrow derived macrophages (BMDM) from the young and adult mouse upon stimulation with different pathogen-associated molecular patterns (PAMPs). Techniques such as flow cytometry and reverse transcription-quantitative polymerase chain reaction (RTqPCR) would be employed. It was found that BMDM from adult mouse produced a higher level of Tumour Necrosis Factor-alpha (TNFα) as compared to BMDM from young mouse when stimulated with Pam3CysSerLys4 (Pam3CSK4). Further investigation also showed that adult BMDM possibly showed greater phagocytic activity compared to BMDM from young when stimulated with lipopolysaccharide (LPS). Knowledge on the differences in immune responses could facilitate future investigation on the immune mechanisms in children for different infectious diseases. Such findings could then be extrapolated to the signaling pathways which could be modulated to optimize immune response and aid in the development of novel targeted immune therapies for the more vulnerable age group.