Paradoxical modulation of influenza by intranasal administration of non-replicating adenovirus particles.

Respiratory mucosal infection by airborne microbes is a common event that occurs every day. We report here that intranasal administration of non-replicating adenovirus (Ad) particles to mice could either confer rapid protection against influenza virus (IFV) challenge independent of adaptive immunity, or exacerbate influenza by triggering rapid death. The life-or-death outcome hinges on the time interval between Ad administration and IFV challenge in conjunction with specific mouse/IFV strains.

The Yin-Yang arms of vaccines: disease-fighting power versus tissue-destructive inflammation.

The disease-fighting power of vaccines has defeated many pathogens and has been credited with global reduction of mortality and morbidity. However, most vaccine developments focus on the enhancement of effector responses with systemic inflammation and the consequences overlooked. Recent evidence shows that systemic inflammatory phenotypes, acute or chronic, are both detrimental and should be avoided if possible.