Targeting immune checkpoints on myeloid cells: current status and future directions

Area of Science:

• Immunology
• Oncology
• Cancer Research

Background:

• Myeloid cells are abundant in tumors, contributing to immune suppression within the tumor microenvironment (TME).
• Myeloid cells express immune checkpoint molecules, similar to T cells, which promote an immunosuppressive phenotype.
• Key myeloid cell populations in the TME include macrophages, neutrophils, dendritic cells, and myeloid-derived suppressor cells.

Purpose of the Study:

• To review the tumor-promoting functions and immune checkpoint expression of major myeloid cell types.
• To explore the potential of targeting myeloid immune checkpoints as a cancer therapy strategy.
• To discuss advanced therapeutic approaches for precise myeloid checkpoint targeting.

Main Methods:

• Literature review summarizing current research on myeloid cell functions and immune checkpoints.
• Analysis of the role of specific myeloid cell subsets in tumor immunosuppression.
• Evaluation of emerging therapeutic strategies including nanotechnology, cellular therapy, and bispecific antibodies.

Main Results:

• Myeloid cells significantly contribute to the immunosuppressive TME through various mechanisms.
• Immune checkpoints are expressed on myeloid cells, offering potential therapeutic targets.
• Targeting myeloid checkpoints may reverse immune suppression and enhance anti-tumor immunity.

Conclusions:

• Blocking immune checkpoints on myeloid cells presents a promising strategy to overcome TME-mediated immunosuppression.
• Combination therapies utilizing nanotechnology, cellular therapy, and bispecific antibodies can enable precise targeting of myeloid checkpoints.
• These targeted approaches aim to improve cancer treatment efficacy while minimizing systemic adverse effects, balancing therapeutic outcomes and patient safety.