Development of genetically engineered CD4+ and CD8+ T cells expressing TCRs specific for a M. tuberculosis 38-kDa...

Area of Science:

• Immunology
• Microbiology
• Gene Therapy

Background:

• Cell-mediated immunity is crucial for clearing Mycobacterium tuberculosis (M. tuberculosis), an intracellular pathogen.
• Adoptive transfer of M. tuberculosis-specific T cells can confer immunity, but generating sufficient numbers is challenging.
• T cell receptor (TCR) gene modification allows rapid expansion of antigen-specific T cells, but TCRs for intracellular bacterial antigens are underexplored.

Purpose of the Study:

• To isolate and characterize M. tuberculosis antigen-specific TCRs.
• To engineer TCRs for enhanced anti-M. tuberculosis activity.
• To establish a foundation for TCR gene-based immunotherapy against tuberculosis.

Main Methods:

• Isolation of M. tuberculosis 38-kDa antigen-specific, HLA class I and class II-restricted TCRs.
• Minimal murinization of TCR gene C regions by substituting nine amino acids with murine homologs.
• Cloning of wild-type and minimal murinized TCR genes into retroviral vectors for transduction into primary CD4(+) and CD8(+) T cells.

Main Results:

• Successful cloning and transduction of both wild-type and minimal murinized TCR genes into T cells.
• Demonstrated anti-M. tuberculosis activity of engineered T cells.
• Minimal murinized TCRs exhibited higher cell surface expression and stronger anti-M. tuberculosis activity compared to wild-type TCRs.

Conclusions:

• This study reports the first isolation and functional confirmation of TCRs targeting M. tuberculosis antigens.
• Minimal murinization enhances TCR expression and anti-M. tuberculosis efficacy.
• These findings provide a basis for developing novel TCR gene-based immunotherapies for tuberculosis treatment, particularly for immunocompromised individuals.