Journal
FRONTIERS IN MICROBIOLOGY
Volume 7, Issue -, Pages -Publisher
FRONTIERS MEDIA SA
DOI: 10.3389/fmicb.2016.00719
Keywords
M. tuberculosis; PE32/PPE65; CD4(+) T cells; CDS+ T cells; IgG subtyping
Categories
Funding
- Department of Biotechnology, Ministry of Science and Technology, GoI [BT/PR12817/COE/34/23/2015]
Ask authors/readers for more resources
PE/PPE genes, present in cluster with ESAT-6 like genes, are suspected to have a role in antigenic variation and virulence of Mycobacterium tuberculosis. Their roles in immune evasion and immune modulation of host are also well documented. We present evidence that PE32/PPE65 present within the RD8 region are co-operonic, co-transcribed, and co-translated, and play role in modulating host immune responses. Experiments with macrophage cell lines revealed that this protein complex suppresses pro-inflammatory cytokines such as TNF-alpha and IL-6 whereas also inducing high expression of anti-inflammatory IL-10. Immunization of mice with these recombinant proteins dampens an effective Th1 response as evident from reduced frequency of IFN-gamma and IL-2 producing CD41(+) and CD81(+) T cells. IgG sub-typing from serum of immunized mice revealed high levels of IgG1 when compared with IgG2a and IgG2b. Further IgG1/IgG2a ratio clearly demonstrated that the protein complex manipulates the host immune response favorable to the pathogen. Our results demonstrate that the co-transcribed and co-translated PE32 and PPE65 antigens are involved specifically in modulating anti-mycobacterial host immune response by hampering Th1 response.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available