Dengue virus-specific cross-reactive CD8+ human cytotoxic T lymphocytes

Area of Science:

• Immunology
• Virology
• T cell immunology

Background:

• Dengue virus infection poses a significant global health challenge.
• Immune responses, particularly T cell-mediated immunity, are crucial for controlling viral infections.
• Understanding the breadth of T cell responses is vital for vaccine development and disease management.

Purpose of the Study:

• To investigate the characteristics of cytotoxic T lymphocytes (CTL) generated in response to dengue virus infection.
• To determine if these CTL exhibit cross-reactivity against different dengue virus serotypes.
• To identify the viral antigens targeted by these CTL.

Main Methods:

• Peripheral blood mononuclear cells (PBMCs) from a dengue virus type 4-immune donor were stimulated with live dengue virus.
• Generation and characterization of virus-specific CD8+ T lymphocytes (CTL).
• Assessment of CTL lysis of infected cells and cells pulsed with viral antigens using recombinant vaccinia viruses.

Main Results:

• Dengue virus stimulation generated virus-specific, serotype-cross-reactive CD8+ class I-restricted CTL.
• These CTL were capable of lysing dengue virus-infected cells and cells presenting antigens from all four dengue serotypes.
• CTL recognized autologous fibroblasts infected with recombinant vaccinia viruses expressing dengue virus E gene or nonstructural proteins.

Conclusions:

• Both structural and nonstructural dengue virus proteins are targets for cytotoxic T-cell-mediated immunity.
• Serotype-cross-reactive CD8+ CTL may play a significant role in viral clearance during dengue virus infections.
• These findings suggest that CD8+ CTL contribute to virus-induced immunopathology during secondary dengue virus infections.