Development of HLA-A2402/K(b) transgenic mice

Area of Science:

• Immunology
• Transgenic animal models
• Cancer immunotherapy

Background:

• Human Leukocyte Antigen (HLA) class I molecules are crucial for cytotoxic T lymphocyte (CTL) responses.
• Developing HLA-transgenic mouse models is essential for studying HLA-restricted immune responses and optimizing vaccine strategies.
• HLA-A2402 is a common HLA allele, making HLA-A2402-restricted responses a significant area of research for cancer immunotherapy.

Purpose of the Study:

• To develop and characterize HLA-A2402/K(b)-transgenic mice for studying HLA-A24-restricted CTL responses.
• To identify novel HLA-A24-restricted CTL epitopes from human cancer antigens.
• To evaluate the potential of identified epitopes as vaccine candidates for cancer immunotherapy.

Main Methods:

• Generation of HLA-A2402/K(b)-transgenic mice expressing chimeric human-mouse class I molecules.
• Immunization of transgenic mice with known HLA-A24-restricted CTL epitope peptides from various cancer antigens.
• Identification and characterization of novel CTL epitopes using peptide immunization and HLA tetramer staining.
• Assessment of CTL activity and HLA-A2402 restriction, including CD8 dependence.

Main Results:

• The developed HLA-A2402/K(b)-transgenic mice successfully induced HLA-A24-restricted, peptide-specific CTL responses upon immunization.
• A novel HLA-A24-restricted CTL epitope, PSA(152-160), derived from prostate-specific antigen (PSA), was identified.
• The cytotoxic activity against PSA(152-160) was confirmed to be HLA-A2402-restricted and CD8-dependent in the transgenic model.
• PSA(152-160) emerged as a potential candidate peptide for vaccination in HLA-A24(+) prostate cancer patients.

Conclusions:

• HLA-A2402/K(b)-transgenic mice are a valuable tool for identifying HLA-A24-restricted CTL epitopes from human cancer antigens.
• The identified PSA(152-160) epitope holds promise for the development of peptide-based immunotherapy for prostate cancer.
• This model system facilitates the advancement of HLA-A24-restricted cancer vaccine development.