Synthesis and Distribution of CARDS Toxin During Mycoplasma pneumoniae Infection in a Murine Model

Department of Microbiology and Immunology, University of Texas Health Sciences Center at San Antonio, TX, USA.
The Journal of Infectious Diseases (Impact Factor: 6). 09/2011; 204(10):1596-604. DOI: 10.1093/infdis/jir557
Source: PubMed


Mice were infected with Mycoplasma pneumoniae and monitored for the synthesis and distribution of the unique adenosine diphosphate–ribosylating and vacuolating Community
Acquired Respiratory Distress Syndrome (CARDS) toxin in bronchiolar lavage fluid (BALF) and lung. We noted direct relationships
between the concentration of CARDS toxin and numbers of mycoplasma genomes in BALF and the degree of histologic pulmonary
inflammation. Immunostaining of lungs revealed extensive colonization by mycoplasmas, including the detection of CARDS toxin
in the corresponding inflamed airways. Lung lesion scores were higher during the early stages of infection, decreased gradually
by day 14 postinfection, and reached substantially lower values at day 35. Infected mouse immunoglobulin (Ig) M and IgG titers
were positive for CARDS toxin as well as for the major adhesin P1 of M. pneumoniae. These data reinforce the proposed pathogenic role of CARDS toxin in M. pneumoniae–mediated pathologies.

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Available from: Robert Douglas Hardy, Jul 14, 2014
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    • "M. pneumoniae poorly expresses CARDS toxin during in vitro growth but dramatically increases synthesis in vivo [15]. Using specific CARDS toxin assays, we detected and co-localized M. pneumoniae and CARDS toxin in biological fluids of infected animals and human tissue samples [16], [17], [18]. Also, we observed dramatic seroconversion to CARDS toxin in M. pneumoniae-associated pneumonia patients, further indicating that this toxin is synthesized in vivo and possesses highly immunogenic epitopes [11]. "
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