First Author | Sieve AN | Year | 2009 |
Journal | Eur J Immunol | Volume | 39 |
Issue | 2 | Pages | 426-38 |
PubMed ID | 19180464 | Mgi Jnum | J:144473 |
Mgi Id | MGI:3831016 | Doi | 10.1002/eji.200838726 |
Citation | Sieve AN, et al. (2009) A novel IL-17-dependent mechanism of cross protection: respiratory infection with mycoplasma protects against a secondary listeria infection. Eur J Immunol 39(2):426-38 |
abstractText | Immune responses to pathogens occur within the context of current and previous infections. Cross protection refers to the phenomena where infection with a particular pathogen provides enhanced resistance to a subsequent unrelated pathogen in an antigen-independent manner. Proposed mechanisms of antigen-independent cross protection have involved the secretion of IFN-gamma, which activates macrophages, thus providing enhanced innate immunity against the secondary viral or bacterial pathogen. Here we provide evidence that a primary infection with the chronic respiratory pathogen, Mycoplasma pulmonis, provides a novel form of cross protection against a secondary infection with Listeria monocytogenes that is not mediated by IFN-gamma, but instead relies upon IL-17 and mobilization of neutrophils. Mice infected with M. pulmonis have enhanced clearance of L. monocytogenes from the spleen and liver, which is associated with increased numbers of Gr-1(+)CD11b(+) cells and higher levels of IL-17. This enhanced clearance of L. monocytogenes was absent in mice depleted of Gr-1(+) cells or in mice deficient in the IL-17 receptor. Additionally, both the IL-17 receptor and neutrophils were essential for optimal clearance of M. pulmonis. Thus, a natural component of the immune response directed against M. pulmonis was able to enhance clearance of L. monocytogenes. |