cGAS is a cytosolic DNA sensor that activates innate immune responses through production of the second messenger 2’3’-cGAMP, which activates the adaptor STING. cGAS senses dsDNA in a length-dependent but sequence-independent manner, and it cannot discriminate self-DNA from foreign DNA. In normal physiological conditions, cellular DNA is sequestered in the nucleus by nuclear envelope and in mitochondria by mitochondrial membrane. When self-DNA leaks into the cytosol during cellular stress, or during mitosis, the cGAS can be exposed to self-DNA and be activated. Recently, many studies have investigated how cGAS keeps inactive and avoids to be aberrantly activated by self-DNA. Thus, the aim of this narrative review is to summarize the mechanisms by which cGAS avoids to sense self-DNA under normal physiological conditions.

Bovine respiratory disease is still a major concern in feedlots and has major economic impact. Another consequence of respiratory infections is the use of antimicrobial molecules to control bacterial pathogens. This can participate to the emergence and shedding of antimicrobial re-sistance that can threaten animal as well as human health. Appeasing pheromones with their capacity to reduce stress and thus their ability to preserve the functions of the immune system have been proposed to reduce the use of antimicrobial substances. In the current report we as-sessed the effect of appeasing pheromone administration on bovine health and performance during the fattening period. Zootechnical and health parameters as well as whole blood immune transcript expressions were measured over weeks in young bulls to determine the effect of the pheromone. We observed a reduction of clinical signs at day 30 in young bulls who received the pheromone and a higher expression of interleukin 8 transcripts in this group than in the control group. Our results are in line with previous reports in bovine and other mammals and ask for further studies to shed more light on the beneficial impact of appeasing pheromones and to de-cipher their exact mechanisms of action.