Plasmacytoid dendritic cells and their Toll-like receptor 9 expression selectively decrease with age

Area of Science:

• Immunology
• Cell Biology
• Gerontology

Background:

• Dendritic cells (DCs) are vital for initiating immune responses against pathogens and tumors.
• The influence of aging, anthropometrics, and gender on human DC function remains unclear.

Purpose of the Study:

• To investigate the impact of age, body mass index, and gender on the quantity and function-associated molecule expression of blood dendritic cells (DCs) in humans.

Main Methods:

• Utilized 4-color flow cytometry to analyze blood DCs from 50 healthy volunteers aged 19-84.
• Examined DC subsets (plasmacytoid and myeloid) and expression of molecules like Toll-like receptor 9 (TLR9).

Main Results:

• Increasing age correlated with a decrease in plasmacytoid DCs, but not myeloid DCs.
• Age was associated with reduced Toll-like receptor 9 (TLR9) expression specifically in plasmacytoid DCs.
• Gender and body mass index showed no significant impact on DC numbers or molecule expression.

Conclusions:

• Age selectively affects plasmacytoid DCs and their TLR9 expression.
• This age-related alteration in DC function may heighten vulnerability to infections and cancers.