Mycobacterium bovis BCG-induced granuloma formation depends on gamma interferon and CD40 ligand but does not require CD28. Infect Immun 2001 Apr;69(4):2596-603
Date
03/20/2001Pubmed ID
11254624Pubmed Central ID
PMC98196DOI
10.1128/IAI.69.4.2596-2603.2001Scopus ID
2-s2.0-0035077708 (requires institutional sign-in at Scopus site) 42 CitationsAbstract
Progressive granuloma formation is a hallmark of chronic mycobacterial infection. Granulomas are localized, protective inflammatory reactions initiated by CD4+ T cells, which contribute to control of bacterial growth and blockade of bacterial dissemination. In order to understand the costimulatory requirements that allow CD4+ T cells to directly or indirectly induce granulomas, we studied granuloma formation after 6 weeks in Mycobacterium bovis BCG-infected CD28- and CD40 ligand (CD40L)-deficient mice and compared it to granuloma formation in infected wild-type inbred mice and infected cytokine-deficient mice. We characterized granulomas morphologically in liver sections, analyzed granuloma infiltrating cells by flow cytometry, and measured cytokine production by cultured granuloma cells. CD28-deficient mice have no defect at the local inflammatory site, inasmuch as they form protective granulomas and control bacterial growth. However, there are fewer activated T cells in the spleen compared to infected wild-type animals, and quantitative differences in the cellular composition of the granuloma are observed by flow cytometry. In CD40L-deficient mice, the granuloma phenotype is very similar to the phenotype in gamma interferon (IFN-gamma)-deficient mice. Both IFN-gamma-deficient and CD40L-deficient mice form granulomas which prevent bacterial dissemination, but control of bacterial growth is significantly impaired. The relative proportion of CD4+ T cells in granulomas from both CD28(-/-) and CD40L(-/-) mice is significantly decreased compared with wild-type animals. Both models demonstrate that the phenotype and activation stage of systemic T cells do not always correlate with the phenotype and activation stage of the localized granulomatous response.
Author List
Hogan LH, Markofski W, Bock A, Barger B, Morrissey JD, Sandor MAuthor
Brittany Player DO Assistant Professor in the Pediatrics department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsCD28 Antigens
CD40 Ligand
Granuloma
Immunophenotyping
Interferon-gamma
Liver
Mice
Mice, Inbred C57BL
Mycobacterium bovis
T-Lymphocytes
Tuberculosis









