Discovering naturally processed antigenic determinants that confer protective T cell immunity

Area of Science:

• Immunology
• Vaccinology
• Proteomics

Background:

• CD8+ T cells (TCD8) are vital for immunity against infectious diseases, making their targets promising for vaccine design.
• Current methods struggle to identify TCD8 epitopes that confer protective immunity during infection, hindering rational vaccine development.

Purpose of the Study:

• To develop a proteomics-based strategy for discovering naturally processed TCD8 determinants from complex pathogens like vaccinia virus (VACV).
• To identify specific VACV epitopes recognized by human T cells and assess their potential to induce protective immunity.

Main Methods:

• Utilized a proteomics approach to identify naturally processed VACV determinants presented by common HLA class I supertypes.
• Immunologically characterized determinant recognition by human peripheral blood cells and HLA class I-transgenic mouse TCD8.
• Assessed the capacity of identified determinants to elicit protective TCD8 immunity against VACV challenge.

Main Results:

• Discovered numerous previously unidentified VACV determinants recognized by human T cells from smallpox-vaccinated individuals.
• Demonstrated that many of these determinants were also recognized by TCD8 in HLA class I-transgenic mice.
• Showed that these determinants elicited protective TCD8 immunity against lethal VACV infection in mice.

Conclusions:

• Efficient processing, presentation, and precursor availability are sufficient for driving protective TCD8 responses.
• The described proteomics approach can define protective TCD8 immunity targets in complex pathogens.
• This strategy has broad applicability for vaccine design against various human pathogens.