Skip to main page content
Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Comparative Study
, 24 (3), 326-31

Alveolar Macrophage Cell Line MH-S Is Valuable as an in Vitro Model for Legionella Pneumophila Infection

Comparative Study

Alveolar Macrophage Cell Line MH-S Is Valuable as an in Vitro Model for Legionella Pneumophila Infection

K Matsunaga et al. Am J Respir Cell Mol Biol.


Alveolar macrophages are the preferential site for growth of Legionella pneumophila (Lp) during infection. However, the study of Lp infection in alveolar macrophages is difficult due to the limitation of available primary alveolar macrophages. In the present study, we established an in vitro Lp infection model in alveolar macrophages using a continuous cell line of murine alveolar macrophages designated MH-S. Infection of both MH-S cells and primary mouse alveolar macrophages obtained by alveolar lavage with virulent L. pneumophila (Lp-V) showed vigorous growth of the bacteria, but infection with avirulent L. pneumophila (Lp-Av) resulted in only minimum growth. Cytokine message expression determination in the MH-S cells after infection showed strong induction of interleukin (IL)-6, IL-10, and tumor necrosis factor-alpha messages induced by Lp-V but minimal induction of these cytokines by Lp-Av infection. IL-1 alpha protein secretion and the message levels for IL-1 alpha were also analyzed, and remarkable induction of IL-1 alpha was evident in both macrophage types when infected with Lp-V. Analysis of IL-12 p40 responses of both macrophage types to Lp-V infection assessed by reverse transcriptase/polymerase chain reaction revealed induction of increased message levels, but significant levels were induced only slowly. Determination of IL-12 protein secretion by enzyme-linked immunosorbent assay of culture supernatants from both macrophage types infected with either Lp-V or Lp-Av showed only minimum production. Thus, MH-S alveolar macrophages showed a similar response to Lp infection compared with primary alveolar macrophages and can be a useful in vitro model system to study Lp infection. The study also revealed the restricted IL-12 protein secretion of alveolar macrophages by Lp infection.

Similar articles

See all similar articles

Cited by 18 PubMed Central articles

See all "Cited by" articles

Publication types

MeSH terms