Ozone exposed epithelial cells modify cocultured natural killer cells

Area of Science:

• Immunology
• Environmental Health
• Cell Biology

Background:

• Ozone (O3) is a major air pollutant with significant adverse health effects.
• Nasal epithelial cells (NECs) are primary targets for inhaled pollutants and interact with immune cells.
• Natural killer (NK) cells are present in the nasal environment and play a role in immune responses.

Purpose of the Study:

• To establish a coculture model of NECs and NK cells.
• To investigate how O3 exposure modifies the interaction between NECs and NK cells.
• To determine the mechanisms underlying O3-induced changes in NK cell activity.

Main Methods:

• Coculture of NECs and NK cells.
• Flow cytometry to analyze NK cell immunophenotypes (IFN-γ, IL-4, CD16).
• Assessment of NK cell cytotoxicity and ligand expression (ULBP3, MICA/B).

Main Results:

• Coculturing with O3-exposed NECs decreased NK cell intracellular interferon-γ (IFN-γ) and reduced cytotoxicity.
• O3 exposure increased ULBP3 and MICA/B ligand expression on NECs.
• Blocking ULBP3 and MICA/B reversed the O3-induced effects on NK cell IFN-γ production.

Conclusions:

• O3 exposure alters NK cell activity through direct cell-cell interactions with NECs.
• The interaction is dependent on ULBP3 and MICA/B ligands expressed on NECs.
• This study elucidates a novel mechanism of O3-induced immune modulation in the nasal epithelium.