Previous Article | Next Article ![]()
Infection and Immunity, February 2001, p. 810-815, Vol. 69, No. 2
Departments of Host
Defense,1
Gastroenterology,2 and
Anatomy,3 Osaka City University Graduate
School of Medicine, 1-4-3 Asahi-machi, Abeno-ku, Osaka 545-8585, and
Institute of BCG, Kiyose-shi, Tokyo
204-0022,4 Japan
Received 17 July 2000/Returned for modification 14 September
2000/Accepted 8 November 2000
Granulomatous inflammation is characterized morphologically by a
compact organized collection of macrophages and their derivatives. It
is classified as either a hypersensitivity type or a foreign-body type.
Lipid components of the Mycobacterium tuberculosis cell wall participate in the pathogenesis of infection. Strains of M. tuberculosis have cord factor (trehalose 6,6'-dimycolate [TDM]) on their surface. To clarify host responses to TDM, including immunogenicity and pathogenicity, we have analyzed the footpad reaction, histopathology, and cytokine profiles of experimental granulomatous lesions in immunized and unimmunized mice challenged with
TDM. In the present study, we have demonstrated for the first time that
TDM can induce both foreign-body-type (nonimmune) and hypersensitivity-type (immune) granulomas by acting as a nonspecific irritant and T-cell-dependent antigen. Immunized mice challenged with
TDM developed more severe lesions than unimmunized mice. At the active
lesion, we found monocyte chemotactic, proinflammatory, and
immunoregulatory cytokines. The level was enhanced in immunized mice
challenged with TDM. This result implies that both nonimmune and immune
mechanisms participate in granulomatous inflammation induced by
mycobacterial infection. Taken together with a previous report, this
study shows that TDM is a pleiotropic molecule against the host and
plays an important role in the pathogenesis of tuberculosis.
0019-9567/01/$04.00+0 DOI: 10.1128/IAI.69.2.810-815.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.
Trehalose 6,6'-Dimycolate (Cord Factor) of
Mycobacterium tuberculosis Induces Foreign-Body- and
Hypersensitivity-Type Granulomas in Mice
*
Corresponding author. Mailing address: Department of
Host Defense, Osaka City University Graduate School of Medicine, 1-4-3 Asahi-machi, Abeno-ku, Osaka 545-8585, Japan. Phone: 81-6-6645-3746. Fax: 81-6-6645-3747. E-mail:
yamagami{at}med.osaka-cu.ac.jp.
This article has been cited by other articles:
| J. Bacteriol. | J. Virol. | Eukaryot. Cell |
|---|
| Microbiol. Mol. Biol. Rev. | Clin. Vaccine Immunol. | All ASM Journals |
|---|