Adding Environmental Insult to Injury: Oxidant Pollutants Add to Inflammatory Cytokine Release in Response to Rhinoviral Infection

E. William Spannhake
The Johns Hopkins Bloomberg School of Public Health
P30ES03819

Background: Cold viruses and environmental pollutants cause respiratory cells to release inflammatory cytokines which contribute to the general malaise people feel when they have respiratory symptoms. Cytokines are cellular inflammatory components that cause inflammation, which leads to the release of fluids, swelling, and other symptoms. Not everyone reacts the same way to the combined insult of respiratory infection and pollutant exposure. Asthmatics are particularly susceptible to the combined adverse effects.

Advance: Researchers at The Johns Hopkins Bloomberg School of Public Health determined that the combined effects of NO2 or O3 and rhinoviral infection in cultured respiratory cells rapidly increased the release of the inflammatory cytokine interleukin-8 through oxidant-dependent mechanisms. The combined effects ranged from 42% to 250% greater than additive for NO2 and from 41% to 67% for O3. The effect was lessened by treatment of the cells with the antioxidant N-acetylcysteine.

Implication: These results indicate that oxidant pollutants can increase the production of proinflammatory cytokines by rhinoviral infected cells and suggest that viral-induced inflammation in upper and lower airways may be exacerbated by con-current exposure to ambient levels of oxidants commonly encountered in the indoor and outdoor environments.

Citation: Spannhake EW, Reddy SPM, Jacob DB, Yu X-Y, Saatian B, Tian J. Synergism between rhinovirus infection and oxidant pollutant exposure enhances airway epithelial cell cytokine production. Environmental Health Perspectives, 110:7, 665-670.