http://www.ncbi.nlm.nih.gov/pubmed/23001692
Inflammation. 2012 Sep 22. [Epub ahead of print]
Mycoplasma pneumoniae Extract Induces an IL-17-Associated Inflammatory Reaction in Murine Lung: Implication for Mycoplasmal Pneumonia.
Kurai D, Nakagaki K, Wada H, Saraya T, Kamiya S, Fujioka Y, Nakata K, Takizawa H, Goto H.
Department of Respiratory Medicine, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka-shi, Tokyo, 181-8611, Japan.
Abstract
Mycoplasma pneumoniae (Mp) may cause immune cell reactions as pivotal aspects of this clinically common respiratory pathogen. Our aim is to determine if Mp extract induces a cellular immune response associated with interleukin (IL)-17, leading to lung inflammation and lung injury. BALB/c mice were immunized with Mp extract intraperitoneally followed by its intratracheal administration, to mimic repeated Mp infection found in humans (repeated inoculation, RI group). Those with a single inoculation were compared as single inoculation group (SI group). Analysis of bronchoalveolar lavage fluid (BALF) demonstrated that keratinocyte-derived cytokine, tumor necrosis factor-α, and IL-6 were produced and peaked on days 0.5 or 1, followed by IL-17 on day 2. Levels of these mediators in BALF were higher in RI group than SI group (P < 0.05). Further, significantly more neutrophils were recruited to the lungs of the RI group (P < 0.05). These observations suggest that IL-17 is involved in the prolonged induction of neutrophils in mice treated with Mp extract.
