%0 Journal Article %A Rafiei, Ali Reza %A Kuade, Yukido %T Identification of CD4+ T-cell Epitopes on Mycobacterium Tuberculosis- Secreted MPB51 Protein in C57BL/6 Mice %J Avicenna Journal of Clinical Medicine %V 12 %N 4 %U http://sjh.umsha.ac.ir/article-1-514-en.html %R %D 2006 %K Epitope Mapping, Epitope, T-cell, Mice, Tuberculosis, %X Introduction & Objective: Both CD4+ type 1 helper (Th1) cells and CD8+ T cells play effective roles in protection against Mycobacterium tuberculosis infection. DNA vaccine encoding MPB51 can induce Th1-type immune responses and protective immunity upon challenge with M.tuberculosis. This study address to identify T-cell immunodominant epitopes on MPB51 in C57BL/6 mice. Materials & Methods : We cloned DNA encoding MPB51 molecule in pCI plasmid. After constructing MPB51 DNA-covered gold cartridge, C57BL/6 mice were immunized by using a gene gun system. Two weeks after the last immunization, the immune spleen cells were cultured in the presence of a synthetic overlapping library peptides covering the mature MPB51 sequence or medium alone. Intracellular and cell culture supernatant gamma interferon (IFN-g) production was analyzed using flow cytometry and ELISA, respectively. Results : Mapping of T-cell epitopes on MPB51 molecule was performed in the spleen lymphocytes restimulated by 20-mer overlapping synthetic peptides of mature MPB51 sequence. Flow cytometric analysis with intracellular IFN-g and the T-cell phenotype revealed that P171-190 and P191-210 peptides contain immunodominant CD4+ T-cell epitopes. Further analysis by using T-cell subset depletion and serial peptide dilution revealed that P171 and p191 are H2-Ab-restricted dominant and subdominant CD4+ T cell epitopes, respectively. Conclusion: This study proved that vaccination with plasmid DNA encoding M. tuberculosis-secreted MPB51 protein not only induce CD4+ T cells immune response but also is an appropriate method for identifying immunogenic peptides. %> http://sjh.umsha.ac.ir/article-1-514-en.pdf %P 28-35 %& 28 %! Identification of CD4+ T-cell Epitopes on Mycobacterium Tuberculosis- Secreted MPB51 Protein in C57BL/6 Mice %9 Original %L A-10-2-460 %+ %G eng %@ 2588-722X %[ 2006