Skip to main page content
U.S. flag

An official website of the United States government

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 1988 May;56(5):1232-6.
doi: 10.1128/iai.56.5.1232-1236.1988.

Mycobacterial lipoarabinomannan inhibits gamma interferon-mediated activation of macrophages

L D Sibley  1 , S W Hunter, P J Brennan, J L Krahenbuhl
Affiliations

Mycobacterial lipoarabinomannan inhibits gamma interferon-mediated activation of macrophages

L D Sibley et al. Infect Immun. 1988 May.

Abstract

The principal efferent role of the macrophage in acquired resistance to intracellular pathogens depends on activation by T-cell lymphokines, primarily gamma interferon (IFN-gamma). However, mouse macrophages that are heavily burdened with Mycobacterium leprae are refractory to activation by IFN-gamma and are thus severely compromised in their capacity for both enhanced microbicidal and tumoricidal activities. We report here that lipoarabinomannan (LAM), a highly immunogenic lipopolysaccharide that is a prominent component of the cell walls of M. leprae and M. tuberculosis, was a potent inhibitor of IFN-gamma-mediated activation of mouse macrophages in vitro. Inhibition of macrophage activation by LAM required preincubation for approximately 24 h, resulting in uptake of LAM into cytoplasmic vacuoles of macrophages. Intact LAM was necessary to inhibit IFN-gamma-mediated activation, as this property was lost when the acyl side chains were removed from LAM by mild alkaline hydrolysis. In addition, LAM was an abundant constituent of macrophages isolated from lepromatous granulomas of M. leprae-infected nude mice and likely contributed to the defective activation of granuloma macrophages by IFN-gamma.

PubMed Disclaimer

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Bull World Health Organ. 1974;51(5):451-65 - PubMed
    1. Clin Exp Immunol. 1971 Dec;9(6):821-31 - PubMed
    1. J Biochem. 1977 Dec;82(6):1759-70 - PubMed
    1. Clin Exp Immunol. 1979 Feb;35(2):250-7 - PubMed
    1. Proc Natl Acad Sci U S A. 1979 Apr;76(4):1962-6 - PubMed

Publication types

MeSH terms

LinkOut - more resources