Boosting with a DNA vaccine expressing ESAT-6 (DNAE6) obliterates the protection imparted by recombinant BCG (rBCGE6) against aerosol Mycobacterium tuberculosis infection in guinea pigs.
Owing to its highly immunodominant nature and ability to induce long-lived memory immunity, ESAT-6, a prominent antigen of Mycobacterium tuberculosis, has been employed in several approaches to develop tuberculosis vaccines. Here, for the first time, we combined ESAT-6 based recombinant BCG (rBCG) and DNA vaccine (DNAE6) in a prime boost approach. Interestingly, in spite of inducing an enhanced antigen specific IFN-gamma response in mice, a DNAE6 booster completely obliterated the protection imparted by rBCG against tuberculosis in guinea pigs. Analysis of immunopathology and cytokine responses suggests involvement of an exaggerated immunity behind the lack of protection imparted by this regimen.
Dey
Bappaditya
B
Department of Biochemistry, University of Delhi South Campus, Benito Juarez Road, New Delhi 110021, India.
Jain
Ruchi
R
Khera
Aparna
A
Rao
Vivek
V
Dhar
Neeraj
N
Gupta
Umesh D
UD
Katoch
V M
VM
Ramanathan
V D
VD
Tyagi
Anil K
AK
D000818:Animals; D000942:Antigens, Bacterial / Q000276:immunology*; D001500:BCG Vaccine / Q000276:immunology*; D001426:Bacterial Proteins / Q000276:immunology*; D005260:Female; D006168:Guinea Pigs; D007117:Immunization, Secondary; D007371:Interferon-gamma / Q000276:immunology; D008168:Lung / Q000276:immunology / Q000382:microbiology / Q000473:pathology; D051379:Mice; D008807:Mice, Inbred BALB C; D009169:Mycobacterium tuberculosis / Q000276:immunology; D013154:Spleen / Q000276:immunology / Q000382:microbiology / Q000473:pathology; D014397:Tuberculosis, Pulmonary / Q000276:immunology / Q000517:prevention & control*; D019444:Vaccines, DNA / Q000276:immunology
D000942:Antigens, Bacterial; D001500:BCG Vaccine; D001426:Bacterial Proteins; C093276:ESAT-6 protein, Mycobacterium tuberculosis; D019444:Vaccines, DNA; D007371:Interferon-gamma