Format

Send to

Choose Destination
See comment in PubMed Commons below
J Vet Sci. 2016 Dec 30;17(4):505-513. doi: 10.4142/jvs.2016.17.4.505.

Mycobacterium vaccae induces a strong Th1 response that subsequently declines in C57BL/6 mice.

Author information

  • 1College of Animal Science and Technology, Jilin Agricultural University, Changchun 130118, China.
  • 2College of Biological Science, Changchun Teacher University, Changchun 130032, China.

Abstract

Mycobacterium (M.) vaccae is a fast-growing species of saprophytic bacteria that is widely distributed. To understand the host immune responses induced by M. vaccae isolated from bovine submaxillary lymph nodes, C57BL/6 mice were infected with reference strain M. bovis Bacillus Calmette-Guérin (BCG) and isolated M. vaccae using intraperitoneal injections. Comparison of the bacterial replication and organ pathology between M. vaccae and M. bovis BCG revealed that M. vaccae was more malignant than M. bovis in mice. We also demonstrated that serum from the M. vaccae-infected mice contained a higher expression level of gamma-interferon (IFN-γ), tumor necrosis factor alpha, monocyte chemoattractant protein-1, interleukin (IL)-4, IL-12, IL-10 and transforming growth factor beta than did the other groups, especially after week 4. Furthermore, when the numbers of CD3⁺CD4⁺IFN-γ⁺ and CD3⁺CD4⁺IL4⁺cells in the infected mice were observed by flow cytometry, we found that a powerful T helper 1 (Th1) response was induced by M. vaccae infection, which was associated with the emergence of CD3⁺CD4⁺IFN-γ⁺cells. However, the Th1 response declined over time, which was associated with appearance of the CD4⁺CD25⁺FoxP3⁺ and CD4⁺CD25⁺CD152⁺Treg cell reaction. In addition, a strong Th2 response was found. Finally, we found that M. vaccae infection increased the production of type I IFNs, which was associated with a reduced Th1 response.

KEYWORDS:

Mycobacterium bovis Bacillus Calmette-Guérin; Mycobacterium vaccae; Th1 cells response; regulatory T cell

PMID:
27994210
PMCID:
PMC5204028
DOI:
10.4142/jvs.2016.17.4.505
[PubMed - in process]
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for The Korean Society of Veterinary Science Icon for PubMed Central
    Loading ...
    Support Center