A new role of the complement system: C3 provides protection in a mouse model of lung infection with intracellular Chlamydia psittaci.

ABSTRACT: The complement system modulates the intensity of innate and specific immunity. While it protects against infections by extracellular bacteria its role in infection with obligate intracellular bacteria, such as the avian and human pathogen Chlamydia (C.) psittaci, is still unknown. In the present study, knockout mice lacking C3 and thus all main complement effector functions were intranasally infected with C. psittaci strain DC15. Clinical parameters, lung histology, and cytokine levels were determined. A subset of infections was additionally performed with mice lacking C5 or C5a receptors. Complement activation occurred before symptoms of pneumonia appeared. Mice lacking C3 were ∼100 times more susceptible to the intracellular bacteria compared to wild-type mice, with all C3(-/-) mice succ

SUBMITTER: Bode J 

PROVIDER: S-EPMC3506576 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature