Circulating regulatory T cells (CD4+CD25+FOXP3+) decrease in breast cancer patients after vaccination with a modified...

Area of Science:

• Immunology
• Oncology
• Vaccinology

Background:

• Regulatory T cells (T(Reg)), characterized as CD4(+)CD25(+)FOXP3(+), play a crucial role in immune suppression within the tumor microenvironment.
• Understanding T(Reg) cell dynamics is vital for developing effective cancer immunotherapies.

Purpose of the Study:

• To analyze the impact of the modified HLA class II HER2/neu peptide (AE37) vaccine on T(Reg) cell populations in breast cancer patients.
• To correlate changes in T(Reg) cell levels with vaccine-specific immune responses.

Main Methods:

• Peripheral blood lymphocytes (PBL) from breast cancer patients were analyzed for T(Reg) cell counts.
• Immune responses were assessed using IFN-γ ELISPOT and dermal delayed-type hypersensitivity (DTH) tests.
• Correlations between T(Reg) cell levels and immune responses were evaluated.

Main Results:

• A significant decrease in mean CD4(+)CD25(+)FOXP3(+) T(Reg) cells was observed post-vaccination.
• No significant changes were noted in serum TGF-β levels.
• IFN-γ ELISPOT and DTH responses increased after AE37 vaccination.
• A strong correlation was found between T(Reg) cell reduction and the size of DTH to AE37.

Conclusions:

• The AE37 vaccine effectively reduces T(Reg) cells in breast cancer patients.
• The observed reduction in T(Reg) cells is associated with enhanced vaccine-specific immune responses, including DTH.
• These findings suggest the AE37 vaccine holds potential clinical utility in cancer immunotherapy.