Cell-mediated immune responses of healthy laboratory volunteers to sonicate antigens prepared from the most prevalent strains of Mycobacterium tuberculosis from South India harboring a single copy of IS6110.
Our restriction fragment length polymorphism (RFLP) studies have shown that the most prevalent (40%) strains of Mycobacterium tuberculosis from South India contain a single copy of the IS6110 insertion sequence and are of importance in studying virulence and immunity. Sonicate antigens from seven such strains were used to study in vitro T-cell proliferation and gamma interferon (IFN-gamma) and interleukin-12 (IL-12) secretion as markers of protective immunity in 25 healthy subjects positive for purified protein derivative (PPD). The standard PPD and heat-killed H37Rv antigens induced the maximum levels of T-cell proliferation and IFN-gamma secretion but low levels of IL-12. All sonicate antigens induced T-cell proliferation and IFN-gamma secretion with strong positive correlation. Our results suggest that sonicate antigens from the most prevalent and recent strains of M. tuberculosis from clinical isolates have the potential to induce T-cell activation and may allow newer and specific antigens to be further characterized for diagnosis and vaccine development.
Rajavelu
Priya
P
Tuberculosis Research Centre (ICMR), Chennai, India.
Das
Sulochana D
SD
D000942:Antigens, Bacterial / Q000276:immunology*; D004251:DNA Transposable Elements; D006801:Humans; D007111:Immunity, Cellular; D007194:India / Q000453:epidemiology; D007371:Interferon-gamma / Q000097:blood; D018664:Interleukin-12 / Q000097:blood; D008213:Lymphocyte Activation / Q000276:immunology; D009169:Mycobacterium tuberculosis / Q000235:genetics / Q000276:immunology*; D014376:Tuberculosis / Q000453:epidemiology / Q000276:immunology
D000942:Antigens, Bacterial; D004251:DNA Transposable Elements; D018664:Interleukin-12; D007371:Interferon-gamma