T-cell immune responses in Mycobacterium avium-infected mice

Hubbard, R D; Flory, Craig M.; Collins, Frank M.

doi:10.1128/iai.60.1.150-153.1992

Cited by 31 publications

(8 citation statements)

References 20 publications

(20 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Antigen processing occurs after infection with mycobacteria and leads to a complex host response involving multiple arms of the immune system (427,428). Although there is evidence that CD4+ T cells, CD8+ T cells, NK cells, and -y5 T cells (197,237,348) are important factors in this response, there is surprisingly little information about the cellular immune response to NTM. For example, some strains of the MAC induce a chronic, lifelong lung infection in normal mice (102), while more virulent MAC strains cause a disseminated disease associated with high mortality (163).…”

Section: Immune Response Cellular Immunitymentioning

confidence: 99%

The Mycobacterium avium complex.

Inderlied

Kemper

Bermudez

1993

Clinical Microbiology Reviews

View full text Add to dashboard Cite

show abstract

Section: Immune Response Cellular Immunitymentioning

confidence: 99%

The Mycobacterium avium complex.

Inderlied

Kemper

Bermudez

1993

Clinical Microbiology Reviews

View full text Add to dashboard Cite

show abstract

“…However, macrophages can be activated to increase their microbiostatic and microbicidal capacity against M. avium. This activation may occur by T-celldependent (2,28,46,47) as well as, possibly, T-cell-independent mechanisms, such as those involving NK cells (5,18,27,42) or direct macrophage activation by microbial products (11,26,30,41,53). Among other mechanisms, there are two metabolic pathways involved in the microbicidal activity of macrophages: production of reactive oxygen intermediates (ROIs) and production of reactive nitrogen intermediates (RNIs).…”

mentioning

confidence: 99%

Involvement of reactive oxygen intermediates in tumor necrosis factor alpha-dependent bacteriostasis of Mycobacterium avium

Sarmento

Appelberg

1996

Infect Immun

View full text Add to dashboard Cite

We studied the involvement of reactive oxygen intermediates and reactive nitrogen intermediates in the bacteriostasis of two Mycobacterium avium strains differing in virulence by resident peritoneal macrophages. We found that both the highly virulent strain (25291) and the low-virulence strain (1983) of M. avium induced superoxide production but inhibited nitrite production in vitro. This inhibition was due to the production of superoxide, a nitric oxide scavenger. The stimulation of superoxide production was two-to fivefold higher in strain 1983-infected than in strain 25291-infected resident peritoneal macrophages and was independent of contaminating T cells or NK cells. Superoxide secretion was dependent on the tumor necrosis factor (TNF) produced endogenously by the macrophages. This was also true when macrophages were isolated from infected mice. Addition of TNF to the infected resident peritoneal macrophages caused only a slight, albeit significant, increase in superoxide production by strain 25291-infected macrophages. Incubation of resident peritoneal macrophages with different scavengers of reactive oxygen intermediates showed that strain 1983 was susceptible to hydrogen peroxide produced by resident peritoneal macrophages. Strain 25291 was shown to decrease superoxide secretion inside heavily infected bone marrow-derived macrophages. This strain was also shown to be a better trigger for production of reactive oxygen intermediates than strain 1983. In summary, strain 1983 induced high levels of TNF synthesis that acted in an autocrine fashion to stimulate production of reactive oxygen intermediates by macrophages leading to growth restriction mediated by hydrogen peroxide. The highly virulent strain 25291 induced low levels of TNF synthesis, and therefore little reactive oxygen intermediate production, and could also inhibit superoxide production by the infected macrophages.

show abstract

“…BCG vaccine is a live attenuated strain of M. bovis and is used in humans to prevent tuberculosis. Previous studies have demonstrated that BCG vaccine protects against M. avium in animal models (22,33).…”

Section: P65k-egfpmentioning

confidence: 99%

Protection againstMycobacterium aviumby DNA Vaccines Expressing Mycobacterial Antigens as Fusion Proteins with Green Fluorescent Protein

Velaz-Faircloth¹,

Cobb²,

Horstman³

et al. 1999

Infect Immun

View full text Add to dashboard Cite

Mycobacterium avium causes disseminated disease in humans with AIDS, paratuberculosis in ruminants, lymphadenopathy in swine, and tuberculosis in birds. We constructed DNA vaccines expressing mycobacterial antigens as fusion proteins with enhanced green fluorescent protein (EGFP). Plasmids p65K-EGFP, p85A-EGFP, and p85B-EGFP expressed the M. avium 65-kDa antigen, theMycobacterium bovis BCG 85A antigen, and the M. avium 85B antigen, respectively, as EGFP fusion proteins. We visualized protein expression directly in cultured murine fibroblasts and intact muscle. p65K-EGFP expressed fusion protein in a diffuse cytoplasmic pattern, and p85A-EGFP and p85B-EGFP produced a speckled pattern. We vaccinated C57BL/6 mice with three doses of plasmid DNA and then challenged them intraperitoneally with M. avium. Negative controls received saline, and positive controls received one dose of BCG vaccine. Mice in all groups developed disseminated infection with a high burden of organisms. Compared to negative controls, mice vaccinated with p85A-EGFP had an eightfold reduction in spleen M. avium CFU at 4 weeks after infection and a fourfold reduction at 8 weeks, reductions similar to those generated by BCG vaccine. Mice vaccinated with p65K-EGFP had a fourfold CFU reduction at 4 weeks and no effect at 8 weeks. This is the first report of DNA vaccines expressing foreign antigens as fusion proteins with EGFP and the first report of successful DNA vaccination againstM. avium.

show abstract

T-cell immune responses in Mycobacterium avium-infected mice

Abstract: Mycobacterium avium infection was substantially more severe in C57BL/6 (Bcgj) than in (C57BL/6 x DBA/2)Fj hybrid (Bcg') mice both in terms of bacterial growth in the spleens and lungs and in host survival.

Cited by 31 publications

References 20 publications

The Mycobacterium avium complex.

The Mycobacterium avium complex.

Involvement of reactive oxygen intermediates in tumor necrosis factor alpha-dependent bacteriostasis of Mycobacterium avium

Protection againstMycobacterium aviumby DNA Vaccines Expressing Mycobacterial Antigens as Fusion Proteins with Green Fluorescent Protein

Contact Info

Product

Resources

About