Mycobacterium bovis Bacille-Calmette-Guérin Infection Aggravates Atherosclerosis

Moises A. Huaman, Joseph E. Qualls, Shinsmon Jose, Stephanie M. Schmidt, Anissa Moussa, David G. Kuhel, Eddy Konaniah, Ravi K. Komaravolu, Carl J. Fichtenbaum, George S. Deepe, David Y. Hui

Research output: Contribution to journalArticlepeer-review

8 Scopus citations

Abstract

Tuberculosis has been associated with increased risk of atherosclerotic cardiovascular disease. To examine whether mycobacterial infection exacerbates atherosclerosis development in experimental conditions, we infected low-density lipoprotein receptor knockout (Ldlr-/-) mice with Mycobacterium bovis Bacille-Calmette-Guérin (BCG), an attenuated strain of the Mycobacterium tuberculosis complex. Twelve-week old male Ldlr-/- mice were infected with BCG (0.3–3.0x106 colony-forming units) via the intranasal route. Mice were subsequently fed a western-type diet containing 21% fat and 0.2% cholesterol for up to 16 weeks. Age-matched uninfected Ldlr-/- mice fed with an identical diet served as controls. Atherosclerotic lesions in aorta were examined using Oil Red O staining. Changes induced by BCG infection on the immunophenotyping profile of circulating T lymphocytes and monocytes were assessed using flow cytometry. BCG infection increased atherosclerotic lesions in en face aorta after 8 weeks (plaque ratio; 0.021±0.01 vs. 0.013±0.01; p = 0.011) and 16 weeks (plaque ratio, 0.15±0.13 vs. 0.06±0.02; p = 0.003). No significant differences in plasma cholesterol or triglyceride levels were observed between infected and uninfected mice. Compared to uninfected mice, BCG infection increased systemic CD4/CD8 T cell ratio and the proportion of Ly6Clow non-classical monocytes at weeks 8 and 16. Aortic plaque ratios correlated with CD4/CD8 T cell ratios (Spearman’s rho = 0.498; p = 0.001) and the proportion of Ly6Clow non-classical monocytes (Spearman’s rho = 0.629; p < 0.001) at week 16. In conclusion, BCG infection expanded the proportion of CD4+ T cell and Ly6Clow monocytes, and aggravated atherosclerosis formation in the aortas of hyperlipidemic Ldlr-/- mice. Our results indicate that mycobacterial infection is capable of enhancing atherosclerosis development.

Original languageEnglish (US)
Article number607957
JournalFrontiers in immunology
Volume11
DOIs
StatePublished - Dec 18 2020
Externally publishedYes

Keywords

  • Bacille-Calmette-Guérin
  • T cells
  • atherosclerosis
  • inflammation
  • monocytes
  • mycobacterium
  • tuberculosis

ASJC Scopus subject areas

  • Immunology and Allergy
  • Immunology

Fingerprint

Dive into the research topics of 'Mycobacterium bovis Bacille-Calmette-Guérin Infection Aggravates Atherosclerosis'. Together they form a unique fingerprint.

Cite this