By comparing the immune responses of both, young and old mice, to bacterial infection they found that the number of macrophages, one of the major cell populations involved in the elimination of infecting bacteria, decreases rapidly in aged mice. This decline in the number of fighters and the associated weakness of the immune defense may be responsible for the age-associated increase in susceptibility to infections. The HZI researchers have succeeded to enhance the resistance to an infection in aged mice by treating them with a macrophage-specific growth factor. This treatment increases the amount of macrophages in aged mice and improves their capacity to fight the infection. This study has been published in the current issue of the scientific magazine "Journal of Pathology".
The main task of the immune system is to protect the body against invading pathogens. For this purpose, a variety of different cell types and molecular factors work together in a complex network. Together, they compose a highly effective defense front line. As we are getting older, our immune system changes: infections are more frequent and more severe, some immune cell types lose certain properties and their functionality declines in short: the immune system grows old. "Since the immune system protects our body against infections, to keep the immune system young and functional is a crucial factor for a healthy aging," says Eva Medina, head of the HZI research group "Infection Immunology".
Much research effort is now focused on identifying age-related changes in the immune function in the hope of developing intervention strategies. "These therapies aim to strength the resistance of the elderly against infectious pathogens," says Eva Medina. The researchers from the HZI have used young mice, age two to three months, and aged animals, older than 20 months (this is the equivalent of 70 to 80 human years) to investigate specific deficiencies in the immune function tha
|Contact: Dr. Bastian Dornbach|
Helmholtz Association of German Research Centres