Cell Death Protects from Pseudomonas Pneumonia

St. Jude Children's Research Hospital (ALSAC)
Friday, 20 October 2000

(Memphis, Tennessee, October 20, 2000) An infectious bacteria known to cause death to patients with cystic fibrosis has researchers believing they might have found one of several defense mechanisms against this killer. St. Jude Children's Research Hospital® researcher Erich Gulbins M.D., Ph.D., determined that Pseudomonas aeruginosa infection kills lung cells by activating the CD95/CD95-ligand system. Most of the work was performed at the University of Tuebingen in Germany, however, the last part was done after the move of his group to St. Jude. This article can be found in the October 20 issue of the journal Science.

Pseudomonas aeruginosa is clinically one of the most important class of bacteria because it induces pneumonia and sepsis in cystic fibrosis and immunocompromised patients. Gulbins and his co-workers detected induction of apoptosis by Pseudomonas aeruginosa via the CD95/CD95 ligand system in mammalian cells. Infection of normal mice with Pseudomonas aeruginosa into the lung induced apoptosis or cell death in lung epithelial cells, which was absent in mice lacking CD95 or CD95 ligand. Surprisingly, induction of cell death in the lung was protective against Pseudomonas aeruginosa infection, since CD95/CD95 ligand deficient, but not normal, mice died by pneumonia and sepsis. "The results identify new mechanisms of the host response to Pseudomonas aeruginosa and may lead to a further understanding of the pathophysiology of Pseudomonas aeruginosa infections in cystic fibrosis patients," states Gulbin.

St. Jude Children's Research Hospital, in Memphis, Tennessee, was founded by the late entertainer Danny Thomas. The hospital is an internationally recognized biomedical research center dedicated to finding cures for catastrophic diseases in childhood. The hospital's work is supported through the funds raised by the American Lebanese Syrian Associated Charities® (ALSAC®). All St. Jude patients are treated regardless of their family's ability to pay. ALSAC covers all costs of treatment beyond those reimbursed by third party insurers, and total costs for families who have no insurance.

For more information, or to contact St. Jude Children's Research Hospital (ALSAC), see their website at: www.stjude.org