Format

Send to

Choose Destination
NPJ Vaccines. 2019 Aug 5;4:34. doi: 10.1038/s41541-019-0122-8. eCollection 2019.

An autophagy-inducing and TLR-2 activating BCG vaccine induces a robust protection against tuberculosis in mice.

Author information

1
1Department of Pathology and Laboratory Medicine, University of Texas Health Sciences Center, Houston, TX USA.
2
2Molecular and Translational Medicine, Paul L. Foster School of Medicine Texas Tech University Health Sciences Center, El Paso, TX USA.
3
3Institute of Biosciences and Technology, Texas A&M University Health Science Center, Houston, TX USA.
4
4Division of Immunobiology, Center for Inflammation and Tolerance, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229 USA.
5
5Department of Biological Sciences and Border Biomedical Research Center, University of Texas at El Paso, Houston, TX USA.
6
6Methodist Hospital Research Institute, Houston, TX USA.
7
7Baylor College of Medicine, Houston, TX USA.
#
Contributed equally

Abstract

Mycobacterium bovis BCG is widely used as a vaccine against tuberculosis due to M. tuberculosis (Mtb), which kills millions of people each year. BCG variably protects children, but not adults against tuberculosis. BCG evades phagosome maturation, autophagy, and reduces MHC-II expression of antigen-presenting cells (APCs) affecting T-cell activation. To bypass these defects, an autophagy-inducing, TLR-2 activating C5 peptide from Mtb-derived CFP-10 protein was overexpressed in BCG in combination with Ag85B. Recombinant BCG85C5 induced a robust MHC-II-dependent antigen presentation to CD4 T cells in vitro, and elicited stronger TH1 cytokines (IL-12, IL-1β, and TNFα) from APCs of C57Bl/6 mice increasing phosphorylation of p38MAPK and ERK. BCG85C5 also enhanced MHC-II surface expression of MΦs by inhibiting MARCH1 ubiquitin ligase that degrades MHC-II. BCG85C5 infected APCs from MyD88 or TLR-2 knockout mice showed decreased antigen presentation. Furthermore, BCG85C5 induced LC3-dependent autophagy in macrophages increasing antigen presentation. Consistent with in vitro effects, BCG85C5 markedly expanded both effector and central memory T cells in C57Bl/6 mice protecting them against both primary aerosol infection with Mtb and reinfection, but was less effective among TLR-2 knockout mice. Thus, BCG85C5 induces stronger and longer lasting immunity, and is better than BCG against tuberculosis of mice.

KEYWORDS:

Live attenuated vaccines; Vaccines

Supplemental Content

Full text links

Icon for PubMed Central
Loading ...
Support Center