Int.J.Curr.Microbiol.App.Sci (2014) 3(4): 85-95 85 Original Research Article Evaluation of protective immune expression in response to Mycobacterium tuberculosis culture filtrate antigens Sherif Moussa Hussseiny 1 *, Faten Sayed Bayoumi 2 and Ahmed Mohamed Ali 3 1 Botany department, Faculty of Women For Art, Science and Education, Ain Shams University, Egypt 2 Immunogenetics Department, National Research Centre, Dokki, Giza, Egypt 3 Botany department, Faculty of Women For Art, Science and Education, Ain Shams University, Egypt *Corresponding author ABSTRACT Introduction Tuberculosis (TB) caused by the intracellular bacterium Mycobacterium tuberculosis (MTB) remains a major worldwide health problem responsible for approximately three million deaths annually (Boesen et al.,1995). Even after successful control of the primary TB ISSN: 2319-7706 Volume 3 Number 4 (2014) pp. 85-95 http://www.ijcmas.com Keywords Mycobacterium tuberculosis, protein, protective response and antigens Tuberculosis (TB) caused by the intracellular bacterium Mycobacterium tuberculosis (MTB), remains a major worldwide health problem where it cause approximately three million deaths annually. New vaccines with better protection rates than Bacillus Calmette Guérin (BCG) in current immunization program is urgently needed for TB eradication. Secreted proteins, described as culture filtrate proteins (CFP s), are the main targets of the T-cell response in TB. In current study, we used culture filtrate protein fractions collected at different time points from growth phases of MTB culture. Protective immune response was evaluated by measuring mRNA expression of genes encoding Interlukene 12 (IL12), Interferon Gamma (INF ), Tumor Necrosis factor (TNF) and inducible Nitric Oxide Synthase (iONS) in vaccinated mice after using culture filtrate protein. Fraction that secreted at late growth phase (fraction 3) showed highly significant cytokine and iONS expression. Vaccinated mice were aerogenically challenged with approximately 100 M. tuberculosis bacilli 30 days after vaccination with CFP fractions. Results showed that fraction 3 provided best protective immune response and best protection against MTB, whereas number of viable MTB significantly reduced over the time in lunge of mice challenged with virulent MTB. Partial characterization of CFP fractions exhibited high concentration of MTB antigens (Ag 85B, 45kDa, CFP-10 and ESAT-6) especially those secreted at late growth phase of MTB culture, this explains high protective immune response provided by that fraction. Thus we concluded that this fractions may be used in near future for development of effective vaccination strategies for improving efficacy of currently available TB vaccine or synergy with the currently available drugs.