An efficient combination immunotherapy for antitumor immunity without accelerating cardiac allograft rejection

Area of Science:

• Immunology
• Oncology
• Transplantation Science

Background:

• Immune checkpoint inhibitors (ICIs) show promise for advanced cancers.
• ICI efficacy in solid organ transplant (SOT) recipients is debated.
• Transplantation is vital for end-stage organ disease.

Purpose of the Study:

• To investigate the combined effect of BET protein inhibition and anti-PD-L1 therapy on liver cancer and cardiac allograft survival.
• To explore the underlying mechanisms of PD-L1 regulation in this context.

Main Methods:

• Established a transgenic primary liver cancer mouse model with allogeneic heart transplantation.
• Administered combination immunotherapy (BET inhibitor JQ1 + anti-PD-L1 antibody).
• Analyzed graft survival, immune cell infiltration, PD-L1 expression, and cytokine levels.

Main Results:

• Combination immunotherapy suppressed primary liver cancer progression.
• Allograft rejection was not accelerated by the combination therapy.
• BET inhibition modulated PD-L1 expression and IFN-γ levels post-transplantation.

Conclusions:

• Combined BET protein inhibition and ICI therapy offers a potential strategy for SOT recipients with cancer.
• This approach may overcome the controversy surrounding ICI use in transplant patients.
• Novel therapeutic avenues for managing cancer in SOT recipients are suggested.